Develop Reference

Android Studio: Bluetooth Low Energy BLE Advertisements

on line 370 i need a way to look for a string of 'f's' in the advertisement data from a TI CC2650. I found this template online but I'm looking for specific advertising data. Please let me know what string array I need to look at to find this.
package net.jmodwyer.beacon.beaconPoC;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender;
import android.content.SharedPreferences;
import android.location.Location;
import android.os.Bundle;
import android.os.RemoteException;
import android.preference.PreferenceManager;
import android.text.util.Linkify;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ScrollView;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesClient;
import com.google.android.gms.location.LocationClient;
import net.jmodwyer.ibeacon.ibeaconPoC.R;
import org.altbeacon.beacon.Beacon;
import org.altbeacon.beacon.BeaconConsumer;
import org.altbeacon.beacon.BeaconManager;
import org.altbeacon.beacon.RangeNotifier;
import org.altbeacon.beacon.Region;
import org.altbeacon.beacon.utils.UrlBeaconUrlCompressor;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
/**
* Adapted from original code written by D Young of Radius Networks.
* #author dyoung, jodwyer
*
*/
public class ScanActivity extends Activity implements BeaconConsumer,
GooglePlayServicesClient.ConnectionCallbacks,
GooglePlayServicesClient.OnConnectionFailedListener {
// Constant Declaration
private static final String PREFERENCE_SCANINTERVAL = "scanInterval";
private static final String PREFERENCE_TIMESTAMP = "timestamp";
private static final String PREFERENCE_POWER = "power";
private static final String PREFERENCE_PROXIMITY = "proximity";
private static final String PREFERENCE_RSSI = "rssi";
private static final String PREFERENCE_MAJORMINOR = "majorMinor";
private static final String PREFERENCE_UUID = "uuid";
private static final String PREFERENCE_INDEX = "index";
private static final String PREFERENCE_LOCATION = "location";
private static final String PREFERENCE_REALTIME = "realTimeLog";
private static final String MODE_SCANNING = "Stop Scanning";
private static final String MODE_STOPPED = "Start Scanning";
protected static final String TAG = "ScanActivity";
/*
* Define a request code to send to Google Play services
* This code is returned in Activity.onActivityResult
*/
private final static int
CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private FileHelper fileHelper;
private BeaconManager beaconManager;
private Region region;
private int eventNum = 1;
// This StringBuffer will hold the scan data for any given scan.
private StringBuffer logString;
// Preferences - will actually have a boolean value when loaded.
private Boolean index;
private Boolean location;
private Boolean uuid;
private Boolean majorMinor;
private Boolean rssi;
private Boolean proximity;
private Boolean power;
private Boolean timestamp;
private String scanInterval;
// Added following a feature request from D.Schmid.
private Boolean realTimeLog;
// LocationClient for Google Play Location Services
LocationClient locationClient;
private ScrollView scroller;
private EditText editText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scan);
verifyBluetooth();
PreferenceManager.setDefaultValues(this, R.xml.preferences, false);
BeaconScannerApp app = (BeaconScannerApp)this.getApplication();
beaconManager = app.getBeaconManager();
//beaconManager.setForegroundScanPeriod(10);
region = app.getRegion();
beaconManager.bind(this);
locationClient = new LocationClient(this, this, this);
fileHelper = app.getFileHelper();
scroller = (ScrollView)ScanActivity.this.findViewById(R.id.scanScrollView);
editText = (EditText)ScanActivity.this.findViewById(R.id.scanText);
// Initialise scan button.
getScanButton().setText(MODE_STOPPED);
}
#Override
public void onResume() {
super.onResume();
beaconManager.bind(this);
}
#Override
public void onPause() {
super.onPause();
// Uncommenting the following leak prevents a ServiceConnection leak when using the back
// arrow in the Action Bar to come out of the file list screen. Unfortunately it also kills
// background scanning, and as I have no workaround right now I'm settling for the lesser of
// two evils.
// beaconManager.unbind(this);
}
public String getCurrentLocation() {
/** Default "error" value is set for location, will be overwritten with the correct lat and
* long values if we're ble to connect to location services and get a reading.
*/
String location = "Unavailable";
if (locationClient.isConnected()) {
Location currentLocation = locationClient.getLastLocation();
if (currentLocation != null) {
location = Double.toString(currentLocation.getLatitude()) + "," +
Double.toString(currentLocation.getLongitude());
}
}
return location;
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main_activity_actions, menu);
return super.onCreateOptionsMenu(menu);
}
#Override
public void onBeaconServiceConnect() {}
/**
*
* #param view
*/
public void onScanButtonClicked(View view) {
toggleScanState();
}
// Handle the user selecting "Settings" from the action bar.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.Settings:
// Show settings
Intent api = new Intent(this, AppPreferenceActivity.class);
startActivityForResult(api, 0);
return true;
case R.id.action_listfiles:
// Launch list files activity
Intent fhi = new Intent(this, FileHandlerActivity.class);
startActivity(fhi);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
/**
* Start and stop scanning, and toggle button label appropriately.
*/
private void toggleScanState() {
Button scanButton = getScanButton();
String currentState = scanButton.getText().toString();
if (currentState.equals(MODE_SCANNING)) {
stopScanning(scanButton);
} else {
startScanning(scanButton);
}
}
/**
* start looking for beacons.
*/
private void startScanning(Button scanButton) {
// Set UI elements to the correct state.
scanButton.setText(MODE_SCANNING);
((EditText)findViewById(R.id.scanText)).setText("");
// Reset event counter
eventNum = 1;
// Get current values for logging preferences
SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);
HashMap <String, Object> prefs = new HashMap<String, Object>();
prefs.putAll(sharedPrefs.getAll());
index = (Boolean)prefs.get(PREFERENCE_INDEX);
location = (Boolean)prefs.get(PREFERENCE_LOCATION);
uuid = (Boolean)prefs.get(PREFERENCE_UUID);
majorMinor = (Boolean)prefs.get(PREFERENCE_MAJORMINOR);
rssi = (Boolean)prefs.get(PREFERENCE_RSSI);
proximity = (Boolean)prefs.get(PREFERENCE_PROXIMITY);
power = (Boolean)prefs.get(PREFERENCE_POWER);
timestamp = (Boolean)prefs.get(PREFERENCE_TIMESTAMP);
scanInterval = (String)prefs.get(PREFERENCE_SCANINTERVAL);
realTimeLog = (Boolean)prefs.get(PREFERENCE_REALTIME);
// Get current background scan interval (if specified)
if (prefs.get(PREFERENCE_SCANINTERVAL) != null) {
beaconManager.setBackgroundBetweenScanPeriod(Long.parseLong(scanInterval));
}
logToDisplay("Scanning...");
// Initialise scan log
logString = new StringBuffer();
//Start scanning again.
beaconManager.setRangeNotifier(new RangeNotifier() {
#Override
public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
if (beacons.size() > 0) {
Iterator <Beacon> beaconIterator = beacons.iterator();
while (beaconIterator.hasNext()) {
Beacon beacon = beaconIterator.next();
// Debug - logging a beacon - checking background logging is working.
System.out.println("Logging another beacon.");
logBeaconData(beacon);
}
}
}
});
try {
beaconManager.startRangingBeaconsInRegion(region);
} catch (RemoteException e) {
// TODO - OK, what now then?
}
}
/**
* Stop looking for beacons.
*/
private void stopScanning(Button scanButton) {
try {
beaconManager.stopRangingBeaconsInRegion(region);
} catch (RemoteException e) {
// TODO - OK, what now then?
}
String scanData = logString.toString();
if (scanData.length() > 0) {
// Write file
fileHelper.createFile(scanData);
// Display file created message.
Toast.makeText(getBaseContext(),
"File saved to:" + getFilesDir().getAbsolutePath(),
Toast.LENGTH_SHORT).show();
scanButton.setText(MODE_STOPPED);
} else {
// We didn't get any data, so there's no point writing an empty file.
Toast.makeText(getBaseContext(),
"No data captured during scan, output file will not be created.",
Toast.LENGTH_SHORT).show();
scanButton.setText(MODE_STOPPED);
}
}
/**
*
* #return reference to the start/stop scanning button
*/
private Button getScanButton() {
return (Button)findViewById(R.id.scanButton);
}
/**
*
* #param beacon The detected beacon
*/
private void logBeaconData(Beacon beacon) {
StringBuilder scanString = new StringBuilder();
if (index) {
scanString.append(eventNum++);
}
if (beacon.getServiceUuid() == 0xfeaa) {
if (beacon.getBeaconTypeCode() == 0x00) {
scanString.append(" Eddystone-UID -> ");
scanString.append(" Namespace : ").append(beacon.getId1());
scanString.append(" Identifier : ").append(beacon.getId2());
logEddystoneTelemetry(scanString, beacon);
} else if (beacon.getBeaconTypeCode() == 0x10) {
String url = UrlBeaconUrlCompressor.uncompress(beacon.getId1().toByteArray());
scanString.append(" Eddystone-URL -> " + url);
} else if (beacon.getBeaconTypeCode() == 0x20) {
scanString.append(" Eddystone-TLM -> ");
logEddystoneTelemetry(scanString, beacon);
}
} else {
// Just an old fashioned iBeacon or AltBeacon...
logGenericBeacon(scanString, beacon);
}
logToDisplay(scanString.toString());
scanString.append("\n");
// Code added following a feature request by D.Schmid - writes a single entry to a file
// every time a beacon is detected, the file will only ever have one entry as it will be
// recreated on each call to this method.
// Get current background scan interval (if specified)
if (realTimeLog) {
// We're in realtime logging mode, create a new log file containing only this entry.
fileHelper.createFile(scanString.toString(), "realtimelog.txt");
}
logString.append(scanString.toString());
}
/**
* Logs iBeacon & AltBeacon data.
*/
private void logGenericBeacon(StringBuilder scanString, Beacon beacon) {
// Comment stuff out for whatever reason
/*
if (location) {
scanString.append(" Location: ").append(getCurrentLocation()).append(" ");
}
`
*/
if (uuid) {
scanString.append(" UUID: ").append(beacon.getId1());
if (beacon.getId1().equals("ffffffff-ffff-ffff-ffff-ffffffffffff ")){
scanString.append("WE DID IT!!!!!!!!!!!");
}else{
scanString.append(" WE DID NOT DO IT =( ");
}
/*
if ((beacon.getId1()).equals ("f")){
scanString.append("WE DID IT!!!!!!!!!!!");
}else{
scanString.append(" WE DID NOT DO IT!!!!!!!!!!! ");
}
*/
}
// Making if statements to test for advertising data
/*
if (majorMinor) {
scanString.append(" Maj. Mnr.: ");
if (beacon.getId2() != null) {
scanString.append(beacon.getId2());
}
scanString.append("-");
if (beacon.getId3() != null) {
scanString.append(beacon.getId3());
}
}
if (rssi) {
scanString.append(" RSSI: ").append(beacon.getRssi());
}
if (proximity) {
scanString.append(" Proximity: ").append(BeaconHelper.getProximityString(beacon.getDistance()));
}
if (power) {
scanString.append(" Power: ").append(beacon.getTxPower());
}
if (timestamp) {
scanString.append(" Timestamp: ").append(BeaconHelper.getCurrentTimeStamp());
} */
}
private void logEddystoneTelemetry(StringBuilder scanString, Beacon beacon) {
// Do we have telemetry data?
if (beacon.getExtraDataFields().size() > 0) {
long telemetryVersion = beacon.getExtraDataFields().get(0);
long batteryMilliVolts = beacon.getExtraDataFields().get(1);
long pduCount = beacon.getExtraDataFields().get(3);
long uptime = beacon.getExtraDataFields().get(4);
scanString.append(" Telemetry version : " + telemetryVersion);
scanString.append(" Uptime (sec) : " + uptime);
scanString.append(" Battery level (mv) " + batteryMilliVolts);
scanString.append(" Tx count: " + pduCount);
}
}
/**
*
* #param line
*/
private void logToDisplay(final String line) {
runOnUiThread(new Runnable() {
public void run() {
editText.append(line + "\n");
// Temp code - don't really want to do this for every line logged, will look for a
// workaround.
Linkify.addLinks(editText, Linkify.WEB_URLS);
scroller.fullScroll(View.FOCUS_DOWN);
}
});
}
private void verifyBluetooth() {
try {
if (!BeaconManager.getInstanceForApplication(this).checkAvailability()) {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Bluetooth not enabled");
builder.setMessage("Please enable bluetooth in settings and restart this application.");
builder.setPositiveButton(android.R.string.ok, null);
builder.setOnDismissListener(new DialogInterface.OnDismissListener() {
#Override
public void onDismiss(DialogInterface dialog) {
finish();
System.exit(0);
}
});
builder.show();
}
}
catch (RuntimeException e) {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Bluetooth LE not available");
builder.setMessage("Sorry, this device does not support Bluetooth LE.");
builder.setPositiveButton(android.R.string.ok, null);
builder.setOnDismissListener(new DialogInterface.OnDismissListener() {
#Override
public void onDismiss(DialogInterface dialog) {
finish();
System.exit(0);
}
});
builder.show();
}
}
/* Location services code follows */
#Override
protected void onStart() {
super.onStart();
// Connect the client.
locationClient.connect();
}
#Override
protected void onStop() {
// Disconnect the client.
locationClient.disconnect();
super.onStop();
}
#Override
public void onConnected(Bundle dataBundle) {
// Uncomment the following line to display the connection status.
// Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show();
}
#Override
public void onDisconnected() {
// Display the connection status
Toast.makeText(this, "Disconnected. Please re-connect.",
Toast.LENGTH_SHORT).show();
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
/* Google Play services can resolve some errors it detects.
* If the error has a resolution, try sending an Intent to
* start a Google Play services activity that can resolve
* error.
*/
if (connectionResult.hasResolution()) {
try {
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(
this,
CONNECTION_FAILURE_RESOLUTION_REQUEST);
/*
* Thrown if Google Play services canceled the original
* PendingIntent
*/
} catch (IntentSender.SendIntentException e) {
// Log the error
e.printStackTrace();
}
} else {
/*
* If no resolution is available, display a dialog to the
* user with the error.
*/
Toast.makeText(getBaseContext(),
"Location services not available, cannot track device location.",
Toast.LENGTH_SHORT).show();
}
}
// Define a DialogFragment that displays the error dialog
public static class ErrorDialogFragment extends DialogFragment {
// Global field to contain the error dialog
private Dialog mDialog;
// Default constructor. Sets the dialog field to null
public ErrorDialogFragment() {
super();
mDialog = null;
}
// Set the dialog to display
public void setDialog(Dialog dialog) {
mDialog = dialog;
}
// Return a Dialog to the DialogFragment.
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
return mDialog;
}
}
/*
* Handle results returned to the FragmentActivity
* by Google Play services
*/
#Override
protected void onActivityResult(
int requestCode, int resultCode, Intent data) {
// Decide what to do based on the original request code
switch (requestCode) {
case CONNECTION_FAILURE_RESOLUTION_REQUEST :
/*
* If the result code is Activity.RESULT_OK, try
* to connect again
*/
switch (resultCode) {
case Activity.RESULT_OK :
/*
* TODO - Try the request again
*/
break;
}
}
}
}

Need to cast to string first .toString
if (uuid) {
scanString.append(" UUID: ").append(beacon.getId1());
// Making if statements to look for all f's in advertising data
if (beacon.getId1().toString().equals(Str1)){
scanString.append("\nAlarm ACTIVATED\n");
}else{
scanString.append("\n Alarm NOT active\n");
}
}

Unable to read FNC1 character at the first position of a GS1 128 Barcode using Zbar library?

I have developed an application for barcode decoding in android using Google vision Library for GS1 data matrix and Zbar Library for GS1 128 barcode Unable to read FNC1 character at the first position of a GS1 128 Barcode using Zbar library.
The Zbar library is unable to display any sign of FNC1 character at the start of the Barcode!
Any Solutions. . . .
Instant Help is appreciable . . .
Below is my ZBar Scanner Activity
#SuppressWarnings("deprecation")
public class ZBarFirstScannerActivity extends AppCompatActivity{
//TextView tv;
ImageView iv;
LinearLayout ll;
private Camera mCamera;
private CameraPreview mPreview;
private Handler autoFocusHandler;
private ImageScanner scanner;
private boolean barcodeScanned = false;
private boolean previewing = true;
TextView tv;
static {
System.loadLibrary("iconv");
}
static {
System.loadLibrary("zbarjni");
}
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.barcode_capture1d);
tv = (TextView) findViewById(R.id.textVertical);
tv.setRotation(90);
initToolbar();
autoFocusHandler = new Handler();
mCamera = getCameraInstance();
// Instance barcode scanner
scanner = new ImageScanner();
scanner.setConfig(0, Config.X_DENSITY, 1);
scanner.setConfig(0, Config.Y_DENSITY, 1);
scanner.setConfig(Symbol.CODE128, Config.ENABLE,1);
scanner.setConfig(Symbol.EAN13, Config.ENABLE,1);
mPreview = new CameraPreview(this, mCamera, previewCb, autoFocusCB);
FrameLayout preview = (FrameLayout)findViewById(R.id.cameraPreview);
preview.addView(mPreview);
}
private void initToolbar() {
final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setHomeButtonEnabled(true);
actionBar.setHomeAsUpIndicator(ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha));
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance()
{
Camera c = null;
try
{
c = Camera.open();
} catch (Exception e)
{
//nada
}
return c;
}
private void releaseCamera()
{
if (mCamera != null)
{
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.release();
mCamera = null;
}
}
PreviewCallback previewCb = new PreviewCallback()
{
public void onPreviewFrame(byte[] data, Camera camera)
{
Camera.Parameters parameters = camera.getParameters();
Size size = parameters.getPreviewSize();
Image barcode = new Image(size.width, size.height, "Y800");
barcode.setData(data);
int result = scanner.scanImage(barcode);
if (result != 0)
{
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
SymbolSet syms = scanner.getResults();
for (Symbol sym : syms)
{
barcodeScanned = true;
Intent returnIntent = new Intent();
returnIntent.putExtra("BARCODE", sym.getData());
setResult(MainActivity.BAR_CODE_TYPE_128,returnIntent);
releaseCamera();
finish();
break;
}
}
}
};
// Mimic continuous auto-focusing
AutoFocusCallback autoFocusCB = new AutoFocusCallback()
{
public void onAutoFocus(boolean success, Camera camera)
{
autoFocusHandler.postDelayed(doAutoFocus, 3000);
}
};
private Runnable doAutoFocus = new Runnable()
{
public void run()
{
if (previewing)
mCamera.autoFocus(autoFocusCB);
}
};
public void onPause() {
super.onPause();
releaseCamera();
}
public void onResume(){
super.onResume();
new ZBarFirstScannerActivity();
}
#Override
public void onBackPressed() {
releaseCamera();
finish();
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
}
Below is my Google Scanner Activity
public final class GoogleScannerActivity extends AppCompatActivity {
private static final String TAG = "Barcode-reader";
// intent request code to handle updating play services if needed.
private static final int RC_HANDLE_GMS = 9001;
// permission request codes need to be < 256
private static final int RC_HANDLE_CAMERA_PERM = 2;
// constants used to pass extra data in the intent
public static final String AutoFocus = "AutoFocus";
public static final String UseFlash = "UseFlash";
public static final String BarcodeObject = "Barcode";
Bitmap bmp;
FileOutputStream fos = null;
private Camera c;
Switch aSwitch;
private CameraSource mCameraSource;
private CameraSourcePreview mPreview;
private GraphicOverlay<BarcodeGraphic> mGraphicOverlay;
// helper objects for detecting taps and pinches.
private ScaleGestureDetector scaleGestureDetector;
private GestureDetector gestureDetector;
/**
* Initializes the UI and creates the detector pipeline.
*/
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.barcode_capture2d);
initToolbar();
ActivitySource.caller = this;
mPreview = (CameraSourcePreview) findViewById(R.id.preview);
mGraphicOverlay = (GraphicOverlay<BarcodeGraphic>) findViewById(R.id.graphicOverlay);
boolean autoFocus = true;
boolean useFlash = false;
// Check for the camera permission before accessing the camera. If the
// permission is not granted yet, request permission.
int rc = ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA);
if (rc == PackageManager.PERMISSION_GRANTED) {
createCameraSource(autoFocus, useFlash);
} else {
requestCameraPermission();
}
gestureDetector = new GestureDetector(this, new CaptureGestureListener());
scaleGestureDetector = new ScaleGestureDetector(this, new ScaleListener());
/*Snackbar.make(mGraphicOverlay, "Tap to capture. Pinch/Stretch to zoom",
Snackbar.LENGTH_LONG)
.show();*/
}
private void initToolbar() {
final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setHomeButtonEnabled(true);
actionBar.setHomeAsUpIndicator(ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha));
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
private Camera.Size getBestPreviewSize(int width, int height, Camera.Parameters parameters){
Camera.Size bestSize = null;
List<Camera.Size> sizeList = parameters.getSupportedPreviewSizes();
bestSize = sizeList.get(0);
for(int i = 1; i < sizeList.size(); i++){
if((sizeList.get(i).width * sizeList.get(i).height) >
(bestSize.width * bestSize.height)){
bestSize = sizeList.get(i);
}
}
return bestSize;
}
/**
* Handles the requesting of the camera permission. This includes
* showing a "Snackbar" message of why the permission is needed then
* sending the request.
*/
private void requestCameraPermission() {
Log.w(TAG, "Camera permission is not granted. Requesting permission");
final String[] permissions = new String[]{Manifest.permission.CAMERA};
if (!ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.CAMERA)) {
ActivityCompat.requestPermissions(this, permissions, RC_HANDLE_CAMERA_PERM);
return;
}
final Activity thisActivity = this;
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View view) {
ActivityCompat.requestPermissions(thisActivity, permissions,
RC_HANDLE_CAMERA_PERM);
}
};
Snackbar.make(mGraphicOverlay, R.string.permission_camera_rationale,
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, listener)
.show();
}
#Override
public boolean onTouchEvent(MotionEvent e) {
boolean b = scaleGestureDetector.onTouchEvent(e);
boolean c = gestureDetector.onTouchEvent(e);
return b || c || super.onTouchEvent(e);
}
/**
* Creates and starts the camera. Note that this uses a higher resolution in comparison
* to other detection examples to enable the barcode detector to detect small barcodes
* at long distances.
*
* Suppressing InlinedApi since there is a check that the minimum version is met before using
* the constant.
*/
#SuppressLint("InlinedApi")
private void createCameraSource(boolean autoFocus, boolean useFlash) {
Context context = getApplicationContext();
// A barcode detector is created to track barcodes. An associated multi-processor instance
// is set to receive the barcode detection results, track the barcodes, and maintain
// graphics for each barcode on screen. The factory is used by the multi-processor to
// create a separate tracker instance for each barcode.
BarcodeDetector barcodeDetector = new BarcodeDetector.Builder(context).setBarcodeFormats(Barcode.CODE_128 | Barcode.DATA_MATRIX | Barcode.QR_CODE).build();
BarcodeTrackerFactory barcodeFactory = new BarcodeTrackerFactory(mGraphicOverlay);
barcodeDetector.setProcessor(
new MultiProcessor.Builder<>(barcodeFactory).build());
if (!barcodeDetector.isOperational()) {
// Note: The first time that an app using the barcode or face API is installed on a
// device, GMS will download a native libraries to the device in order to do detection.
// Usually this completes before the app is run for the first time. But if that
// download has not yet completed, then the above call will not detect any barcodes
// and/or faces.
//
// isOperational() can be used to check if the required native libraries are currently
// available. The detectors will automatically become operational once the library
// downloads complete on device.
Log.w(TAG, "Detector dependencies are not yet available.");
// Check for low storage. If there is low storage, the native library will not be
// downloaded, so detection will not become operational.
IntentFilter lowstorageFilter = new IntentFilter(Intent.ACTION_DEVICE_STORAGE_LOW);
boolean hasLowStorage = registerReceiver(null, lowstorageFilter) != null;
if (hasLowStorage) {
Toast.makeText(this, R.string.low_storage_error, Toast.LENGTH_LONG).show();
Log.w(TAG, getString(R.string.low_storage_error));
}
}
// Creates and starts the camera. Note that this uses a higher resolution in comparison
// to other detection examples to enable the barcode detector to detect small barcodes
// at long distances.
CameraSource.Builder builder = new CameraSource.Builder(getApplicationContext(), barcodeDetector)
.setFacing(CameraSource.CAMERA_FACING_BACK)
.setRequestedPreviewSize(1100, 844)
.setRequestedFps(15.0f);
// make sure that auto focus is an available option
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
builder = builder.setFocusMode(
autoFocus ? Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE : null);
}
mCameraSource = builder
.setFlashMode(useFlash ? Camera.Parameters.FLASH_MODE_TORCH : null)
.build();
}
/**
* Restarts the camera.
*/
#Override
protected void onResume() {
super.onResume();
startCameraSource();
}
/**
* Stops the camera.
*/
#Override
protected void onPause() {
super.onPause();
if (mPreview != null) {
mPreview.stop();
}
}
/**
* Releases the resources associated with the camera source, the associated detectors, and the
* rest of the processing pipeline.
*/
#Override
protected void onDestroy() {
super.onDestroy();
if (mPreview != null) {
mPreview.release();
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
#NonNull String[] permissions,
#NonNull int[] grantResults) {
if (requestCode != RC_HANDLE_CAMERA_PERM) {
Log.d(TAG, "Got unexpected permission result: " + requestCode);
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
return;
}
if (grantResults.length != 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Log.d(TAG, "Camera permission granted - initialize the camera source");
// we have permission, so create the camerasource
boolean autoFocus = getIntent().getBooleanExtra(AutoFocus,false);
boolean useFlash = getIntent().getBooleanExtra(UseFlash, false);
createCameraSource(autoFocus, useFlash);
return;
}
Log.e(TAG, "Permission not granted: results len = " + grantResults.length +
" Result code = " + (grantResults.length > 0 ? grantResults[0] : "(empty)"));
DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Multitracker sample")
.setMessage(R.string.no_camera_permission)
.setPositiveButton(R.string.ok, listener)
.show();
}
/**
* Starts or restarts the camera source, if it exists. If the camera source doesn't exist yet
* (e.g., because onResume was called before the camera source was created), this will be called
* again when the camera source is created.
*/
private void startCameraSource() throws SecurityException {
// check that the device has play services available.
int code = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(
getApplicationContext());
if (code != ConnectionResult.SUCCESS) {
Dialog dlg =
GoogleApiAvailability.getInstance().getErrorDialog(this, code, RC_HANDLE_GMS);
dlg.show();
}
if (mCameraSource != null) {
try {
mPreview.start(mCameraSource, mGraphicOverlay);
} catch (IOException e) {
Log.e(TAG, "Unable to start camera source.", e);
mCameraSource.release();
mCameraSource = null;
}
}
}
/**
* onTap is called to capture the oldest barcode currently detected and
* return it to the caller.
*
* #param rawX - the raw position of the tap
* #param rawY - the raw position of the tap.
* #return true if the activity is ending.
*/
private boolean onTap(float rawX, float rawY) {
//TODO: use the tap position to select the barcode.
BarcodeGraphic graphic = mGraphicOverlay.getFirstGraphic();
Barcode barcode = null;
if (graphic != null) {
barcode = graphic.getBarcode();
if (barcode != null) {
Intent data = new Intent();
data.putExtra(BarcodeObject, barcode);
setResult(CommonStatusCodes.SUCCESS, data);
finish();
}
else {
Log.d(TAG, "barcode data is null");
}
}
else {
Log.d(TAG,"no barcode detected");
}
return barcode != null;
}
private class CaptureGestureListener extends GestureDetector.SimpleOnGestureListener {
#Override
public boolean onSingleTapConfirmed(MotionEvent e) {
return onTap(e.getRawX(), e.getRawY()) || super.onSingleTapConfirmed(e);
}
}
private class ScaleListener implements ScaleGestureDetector.OnScaleGestureListener {
/**
* Responds to scaling events for a gesture in progress.
* Reported by pointer motion.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
* #return Whether or not the detector should consider this event
* as handled. If an event was not handled, the detector
* will continue to accumulate movement until an event is
* handled. This can be useful if an application, for example,
* only wants to update scaling factors if the change is
* greater than 0.01.
*/
#Override
public boolean onScale(ScaleGestureDetector detector) {
return false;
}
/**
* Responds to the beginning of a scaling gesture. Reported by
* new pointers going down.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
* #return Whether or not the detector should continue recognizing
* this gesture. For example, if a gesture is beginning
* with a focal point outside of a region where it makes
* sense, onScaleBegin() may return false to ignore the
* rest of the gesture.
*/
#Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
return true;
}
/**
* Responds to the end of a scale gesture. Reported by existing
* pointers going up.
* <p/>
* Once a scale has ended, {#link ScaleGestureDetector#getFocusX()}
* and {#link ScaleGestureDetector#getFocusY()} will return focal point
* of the pointers remaining on the screen.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
*/
#Override
public void onScaleEnd(ScaleGestureDetector detector) {
mCameraSource.doZoom(detector.getScaleFactor());
}
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
}

When scanning a GS1-128 symbol the FNC1 in first position acts as a flag character to indicate the presence of GS1 Application Identifier standard format data and is intentionally omitted from the scanned data, whilst any inter-field FNC1 formatting character is transmitted at GS (ASCII 29).
The implicit, leading FNC1 can be inferred if your reader is configured to emit symbology identifiers at the start of the scanned data. In this case your GS1-128 scanned data will begin with ]C1 rather than ]C0 for generic Code 128.
Unfortunately it does not appear as though either the ZBar library or Google Vision Library can be configured to return symbology identifiers which is a disappointing limitation.
Additionally the Google Vision Library erroneously returns a leading GS1 representing the FNC1 in first position.
Reading of GS1 formatted data is described in detail by this answer.
Specifically the ISO/IEC 15417 - Code 128 bar code symbology specification says:
"Any application which utilizes Code
128 symbols with FNC1 in the first or second data position should
require the transmission of symbology identifiers to be enabled. When
FNC1 is used in the first or second position it shall not be
represented in the transmitted message, although its presence is
indicated by the use of modifier values 1 or 2 respectively in the
symbology identifier."

I need to get torch turn on by toggle Button at on going Camera Activity By adding some more lines of code without touching the existing code

I do have a Barcode Decoding Applcation : https://play.google.com/store/apps/details?id=com.barcodereader
I have Used Zbar library and Google Vision API for Scanning
Now what i want is while scanning the Barcode if user taps on a button at appbar for turning on Torch (Flash) then it should be turn on and off vice-versa.
But the Problem is the camera is already on with its all parameters so when user taps the button to turn on torch we need to interrupt the ongoing Camera parameters and I don't want to do that,
I am searching the other way to get torch on without changing the existing Camera Parameters..
Below is The Camera Activity of ZBar And Google Vision this both use some other Camera Classes for Camera Preview.
#SuppressWarnings("deprecation")
public class ZBarFirstScannerActivity extends AppCompatActivity{
//TextView tv;
ImageView iv;
LinearLayout ll;
private Camera mCamera;
private CameraPreview mPreview;
private Handler autoFocusHandler;
private ImageScanner scanner;
private boolean barcodeScanned = false;
private boolean previewing = true;
TextView tv;
static {
System.loadLibrary("iconv");
}
static {
System.loadLibrary("zbarjni");
}
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.barcode_capture1d);
tv = (TextView) findViewById(R.id.textVertical);
tv.setRotation(90);
initToolbar();
autoFocusHandler = new Handler();
mCamera = getCameraInstance();
// Instance barcode scanner
scanner = new ImageScanner();
scanner.setConfig(0, Config.X_DENSITY, 1);
scanner.setConfig(0, Config.Y_DENSITY, 1);
scanner.setConfig(Symbol.CODE128, Config.ENABLE,1);
scanner.setConfig(Symbol.EAN13, Config.ENABLE,1);
mPreview = new CameraPreview(this, mCamera, previewCb, autoFocusCB);
FrameLayout preview = (FrameLayout)findViewById(R.id.cameraPreview);
preview.addView(mPreview);
}
private void initToolbar() {
final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setHomeButtonEnabled(true);
actionBar.setHomeAsUpIndicator(ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha));
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance()
{
Camera c = null;
try
{
c = Camera.open();
} catch (Exception e)
{
//nada
}
return c;
}
private void releaseCamera()
{
if (mCamera != null)
{
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.release();
mCamera = null;
}
}
PreviewCallback previewCb = new PreviewCallback()
{
public void onPreviewFrame(byte[] data, Camera camera)
{
Camera.Parameters parameters = camera.getParameters();
Size size = parameters.getPreviewSize();
Image barcode = new Image(size.width, size.height, "Y800");
barcode.setData(data);
int result = scanner.scanImage(barcode);
if (result != 0)
{
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
SymbolSet syms = scanner.getResults();
for (Symbol sym : syms)
{
barcodeScanned = true;
Intent returnIntent = new Intent();
returnIntent.putExtra("BARCODE", sym.getData());
setResult(MainActivity.BAR_CODE_TYPE_128,returnIntent);
releaseCamera();
finish();
break;
}
}
}
};
// Mimic continuous auto-focusing
AutoFocusCallback autoFocusCB = new AutoFocusCallback()
{
public void onAutoFocus(boolean success, Camera camera)
{
autoFocusHandler.postDelayed(doAutoFocus, 3000);
}
};
private Runnable doAutoFocus = new Runnable()
{
public void run()
{
if (previewing)
mCamera.autoFocus(autoFocusCB);
}
};
public void onPause() {
super.onPause();
releaseCamera();
}
public void onResume(){
super.onResume();
new ZBarFirstScannerActivity();
}
#Override
public void onBackPressed() {
releaseCamera();
finish();
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
}
And GoogleScanner
public final class GoogleScannerActivity extends AppCompatActivity {
private static final String TAG = "Barcode-reader";
// intent request code to handle updating play services if needed.
private static final int RC_HANDLE_GMS = 9001;
// permission request codes need to be < 256
private static final int RC_HANDLE_CAMERA_PERM = 2;
// constants used to pass extra data in the intent
public static final String AutoFocus = "AutoFocus";
public static final String UseFlash = "UseFlash";
public static final String BarcodeObject = "Barcode";
Bitmap bmp;
FileOutputStream fos = null;
private Camera c;
Switch aSwitch;
private CameraSource mCameraSource;
private CameraSourcePreview mPreview;
private GraphicOverlay<BarcodeGraphic> mGraphicOverlay;
// helper objects for detecting taps and pinches.
private ScaleGestureDetector scaleGestureDetector;
private GestureDetector gestureDetector;
/**
* Initializes the UI and creates the detector pipeline.
*/
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.barcode_capture2d);
initToolbar();
ActivitySource.caller = this;
mPreview = (CameraSourcePreview) findViewById(R.id.preview);
mGraphicOverlay = (GraphicOverlay<BarcodeGraphic>)findViewById(R.id.graphicOverlay);
boolean autoFocus = true;
boolean useFlash = false;
// Check for the camera permission before accessing the camera. If the
// permission is not granted yet, request permission.
int rc = ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA);
if (rc == PackageManager.PERMISSION_GRANTED) {
createCameraSource(autoFocus, useFlash);
} else {
requestCameraPermission();
}
gestureDetector = new GestureDetector(this, new CaptureGestureListener());
scaleGestureDetector = new ScaleGestureDetector(this, new ScaleListener());
/*Snackbar.make(mGraphicOverlay, "Tap to capture. Pinch/Stretch to zoom",
Snackbar.LENGTH_LONG)
.show();*/
}
private void initToolbar() {
final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setHomeButtonEnabled(true);
actionBar.setHomeAsUpIndicator(ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha));
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
private Camera.Size getBestPreviewSize(int width, int height, Camera.Parameters parameters){
Camera.Size bestSize = null;
List<Camera.Size> sizeList = parameters.getSupportedPreviewSizes();
bestSize = sizeList.get(0);
for(int i = 1; i < sizeList.size(); i++){
if((sizeList.get(i).width * sizeList.get(i).height) >
(bestSize.width * bestSize.height)){
bestSize = sizeList.get(i);
}
}
return bestSize;
}
/**
* Handles the requesting of the camera permission. This includes
* showing a "Snackbar" message of why the permission is needed then
* sending the request.
*/
private void requestCameraPermission() {
Log.w(TAG, "Camera permission is not granted. Requesting permission");
final String[] permissions = new String[]{Manifest.permission.CAMERA};
if (!ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.CAMERA)) {
ActivityCompat.requestPermissions(this, permissions, RC_HANDLE_CAMERA_PERM);
return;
}
final Activity thisActivity = this;
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View view) {
ActivityCompat.requestPermissions(thisActivity, permissions,
RC_HANDLE_CAMERA_PERM);
}
};
Snackbar.make(mGraphicOverlay, R.string.permission_camera_rationale,
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, listener)
.show();
}
#Override
public boolean onTouchEvent(MotionEvent e) {
boolean b = scaleGestureDetector.onTouchEvent(e);
boolean c = gestureDetector.onTouchEvent(e);
return b || c || super.onTouchEvent(e);
}
/**
* Creates and starts the camera. Note that this uses a higher resolution in comparison
* to other detection examples to enable the barcode detector to detect small barcodes
* at long distances.
*
* Suppressing InlinedApi since there is a check that the minimum version is met before using
* the constant.
*/
#SuppressLint("InlinedApi")
private void createCameraSource(boolean autoFocus, boolean useFlash) {
Context context = getApplicationContext();
// A barcode detector is created to track barcodes. An associated multi-processor instance
// is set to receive the barcode detection results, track the barcodes, and maintain
// graphics for each barcode on screen. The factory is used by the multi-processor to
// create a separate tracker instance for each barcode.
BarcodeDetector barcodeDetector = new BarcodeDetector.Builder(context).setBarcodeFormats(Barcode.CODE_128 | Barcode.DATA_MATRIX | Barcode.QR_CODE).build();
BarcodeTrackerFactory barcodeFactory = new BarcodeTrackerFactory(mGraphicOverlay);
barcodeDetector.setProcessor(
new MultiProcessor.Builder<>(barcodeFactory).build());
if (!barcodeDetector.isOperational()) {
// Note: The first time that an app using the barcode or face API is installed on a
// device, GMS will download a native libraries to the device in order to do detection.
// Usually this completes before the app is run for the first time. But if that
// download has not yet completed, then the above call will not detect any barcodes
// and/or faces.
//
// isOperational() can be used to check if the required native libraries are currently
// available. The detectors will automatically become operational once the library
// downloads complete on device.
Log.w(TAG, "Detector dependencies are not yet available.");
// Check for low storage. If there is low storage, the native library will not be
// downloaded, so detection will not become operational.
IntentFilter lowstorageFilter = new IntentFilter(Intent.ACTION_DEVICE_STORAGE_LOW);
boolean hasLowStorage = registerReceiver(null, lowstorageFilter) != null;
if (hasLowStorage) {
Toast.makeText(this, R.string.low_storage_error, Toast.LENGTH_LONG).show();
Log.w(TAG, getString(R.string.low_storage_error));
}
}
// Creates and starts the camera. Note that this uses a higher resolution in comparison
// to other detection examples to enable the barcode detector to detect small barcodes
// at long distances.
CameraSource.Builder builder = new CameraSource.Builder(getApplicationContext(), barcodeDetector)
.setFacing(CameraSource.CAMERA_FACING_BACK)
.setRequestedPreviewSize(1100, 844)
.setRequestedFps(15.0f);
// make sure that auto focus is an available option
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
builder = builder.setFocusMode(
autoFocus ? Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE : null);
}
mCameraSource = builder
.setFlashMode(useFlash ? Camera.Parameters.FLASH_MODE_TORCH : null)
.build();
}
/**
* Restarts the camera.
*/
#Override
protected void onResume() {
super.onResume();
startCameraSource();
}
/**
* Stops the camera.
*/
#Override
protected void onPause() {
super.onPause();
if (mPreview != null) {
mPreview.stop();
}
}
/**
* Releases the resources associated with the camera source, the associated detectors, and the
* rest of the processing pipeline.
*/
#Override
protected void onDestroy() {
super.onDestroy();
if (mPreview != null) {
mPreview.release();
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
#NonNull String[] permissions,
#NonNull int[] grantResults) {
if (requestCode != RC_HANDLE_CAMERA_PERM) {
Log.d(TAG, "Got unexpected permission result: " + requestCode);
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
return;
}
if (grantResults.length != 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Log.d(TAG, "Camera permission granted - initialize the camera source");
// we have permission, so create the camerasource
boolean autoFocus = getIntent().getBooleanExtra(AutoFocus,false);
boolean useFlash = getIntent().getBooleanExtra(UseFlash, false);
createCameraSource(autoFocus, useFlash);
return;
}
Log.e(TAG, "Permission not granted: results len = " + grantResults.length +
" Result code = " + (grantResults.length > 0 ? grantResults[0] : "(empty)"));
DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Multitracker sample")
.setMessage(R.string.no_camera_permission)
.setPositiveButton(R.string.ok, listener)
.show();
}
/**
* Starts or restarts the camera source, if it exists. If the camera source doesn't exist yet
* (e.g., because onResume was called before the camera source was created), this will be called
* again when the camera source is created.
*/
private void startCameraSource() throws SecurityException {
// check that the device has play services available.
int code = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(
getApplicationContext());
if (code != ConnectionResult.SUCCESS) {
Dialog dlg =
GoogleApiAvailability.getInstance().getErrorDialog(this, code, RC_HANDLE_GMS);
dlg.show();
}
if (mCameraSource != null) {
try {
mPreview.start(mCameraSource, mGraphicOverlay);
} catch (IOException e) {
Log.e(TAG, "Unable to start camera source.", e);
mCameraSource.release();
mCameraSource = null;
}
}
}
/**
* onTap is called to capture the oldest barcode currently detected and
* return it to the caller.
*
* #param rawX - the raw position of the tap
* #param rawY - the raw position of the tap.
* #return true if the activity is ending.
*/
private boolean onTap(float rawX, float rawY) {
//TODO: use the tap position to select the barcode.
BarcodeGraphic graphic = mGraphicOverlay.getFirstGraphic();
Barcode barcode = null;
if (graphic != null) {
barcode = graphic.getBarcode();
if (barcode != null) {
Intent data = new Intent();
data.putExtra(BarcodeObject, barcode);
setResult(CommonStatusCodes.SUCCESS, data);
finish();
}
else {
Log.d(TAG, "barcode data is null");
}
}
else {
Log.d(TAG,"no barcode detected");
}
return barcode != null;
}
private class CaptureGestureListener extends GestureDetector.SimpleOnGestureListener {
#Override
public boolean onSingleTapConfirmed(MotionEvent e) {
return onTap(e.getRawX(), e.getRawY()) || super.onSingleTapConfirmed(e);
}
}
private class ScaleListener implements ScaleGestureDetector.OnScaleGestureListener {
/**
* Responds to scaling events for a gesture in progress.
* Reported by pointer motion.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
* #return Whether or not the detector should consider this event
* as handled. If an event was not handled, the detector
* will continue to accumulate movement until an event is
* handled. This can be useful if an application, for example,
* only wants to update scaling factors if the change is
* greater than 0.01.
*/
#Override
public boolean onScale(ScaleGestureDetector detector) {
return false;
}
/**
* Responds to the beginning of a scaling gesture. Reported by
* new pointers going down.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
* #return Whether or not the detector should continue recognizing
* this gesture. For example, if a gesture is beginning
* with a focal point outside of a region where it makes
* sense, onScaleBegin() may return false to ignore the
* rest of the gesture.
*/
#Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
return true;
}
/**
* Responds to the end of a scale gesture. Reported by existing
* pointers going up.
* <p/>
* Once a scale has ended, {#link ScaleGestureDetector#getFocusX()}
* and {#link ScaleGestureDetector#getFocusY()} will return focal point
* of the pointers remaining on the screen.
*
* #param detector The detector reporting the event - use this to
* retrieve extended info about event state.
*/
#Override
public void onScaleEnd(ScaleGestureDetector detector) {
mCameraSource.doZoom(detector.getScaleFactor());
}
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
}

android : open chrome custom tab from fragment

I have one Activity MainActivity. It contains a ViewPager hosting a fragment FragmentPlaceHolder. This fragment has a RecyclerView.
Now, on a click of a particular view, say button, inside a RecyclerView item, I want to open a chrome custom tab in new Activity. Can anyone help me with this one ? I am expecting a step wise implemention of Chrome Custom tabs.
Thanks.

So, I did it this way:
First of all, add this following dependency in build.gradle(app):
compile 'com.android.support:customtabs:23.1.1'
First create an activity WebviewActivity:
WebViewActivity.java
public class WebviewActivity extends AppCompatActivity {
public static final String EXTRA_URL = "extra.url";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_webview);
String url = getIntent().getStringExtra(EXTRA_URL);
WebView webView = (WebView)findViewById(R.id.webview);
webView.setWebViewClient(new WebViewClient());
WebSettings webSettings = webView.getSettings();
webSettings.setJavaScriptEnabled(true);
setTitle(url);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
webView.loadUrl(url);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
finish();
return true;
}
return super.onOptionsItemSelected(item);
}
}
Now, say on button click you want to open chrome custom tab and load www.google.com, so, do it as below:
public void onButtonClick(View view){
CustomTabsIntent customTabsIntent = new CustomTabsIntent.Builder().build();
CustomTabActivityHelper.openCustomTab(
this,// activity
customTabsIntent,
Uri.parse("http://www.google.com"),
new WebviewFallback()
);
}
activity_webview.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright 2015 Google Inc. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<WebView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/webview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".helpers.WebviewActivity" />
Then, simply craete the classes as below:
CustomTabActivityHelper.java
import android.app.Activity;
import android.net.Uri;
import android.os.Bundle;
import android.support.customtabs.CustomTabsClient;
import android.support.customtabs.CustomTabsIntent;
import android.support.customtabs.CustomTabsServiceConnection;
import android.support.customtabs.CustomTabsSession;
import java.util.List;
/**
* This is a helper class to manage the connection to the Custom Tabs Service.
*/
public class CustomTabActivityHelper implements ServiceConnectionCallback {
private CustomTabsSession mCustomTabsSession;
private CustomTabsClient mClient;
private CustomTabsServiceConnection mConnection;
private ConnectionCallback mConnectionCallback;
/**
* Opens the URL on a Custom Tab if possible. Otherwise fallsback to opening it on a WebView.
*
* #param activity The host activity.
* #param customTabsIntent a CustomTabsIntent to be used if Custom Tabs is available.
* #param uri the Uri to be opened.
* #param fallback a CustomTabFallback to be used if Custom Tabs is not available.
*/
public static void openCustomTab(Activity activity,
CustomTabsIntent customTabsIntent,
Uri uri,
CustomTabFallback fallback) {
String packageName = CustomTabsHelper.getPackageNameToUse(activity);
//If we cant find a package name, it means theres no browser that supports
//Chrome Custom Tabs installed. So, we fallback to the webview
if (packageName == null) {
if (fallback != null) {
fallback.openUri(activity, uri);
}
} else {
customTabsIntent.intent.setPackage(packageName);
customTabsIntent.launchUrl(activity, uri);
}
}
/**
* Unbinds the Activity from the Custom Tabs Service.
*
* #param activity the activity that is connected to the service.
*/
public void unbindCustomTabsService(Activity activity) {
if (mConnection == null) return;
activity.unbindService(mConnection);
mClient = null;
mCustomTabsSession = null;
mConnection = null;
}
/**
* Creates or retrieves an exiting CustomTabsSession.
*
* #return a CustomTabsSession.
*/
public CustomTabsSession getSession() {
if (mClient == null) {
mCustomTabsSession = null;
} else if (mCustomTabsSession == null) {
mCustomTabsSession = mClient.newSession(null);
}
return mCustomTabsSession;
}
/**
* Register a Callback to be called when connected or disconnected from the Custom Tabs Service.
*
* #param connectionCallback
*/
public void setConnectionCallback(ConnectionCallback connectionCallback) {
this.mConnectionCallback = connectionCallback;
}
/**
* Binds the Activity to the Custom Tabs Service.
*
* #param activity the activity to be binded to the service.
*/
public void bindCustomTabsService(Activity activity) {
if (mClient != null) return;
String packageName = CustomTabsHelper.getPackageNameToUse(activity);
if (packageName == null) return;
mConnection = new ServiceConnection(this);
CustomTabsClient.bindCustomTabsService(activity, packageName, mConnection);
}
/**
* #return true if call to mayLaunchUrl was accepted.
* #see {#link CustomTabsSession#mayLaunchUrl(Uri, Bundle, List)}.
*/
public boolean mayLaunchUrl(Uri uri, Bundle extras, List<Bundle> otherLikelyBundles) {
if (mClient == null) return false;
CustomTabsSession session = getSession();
if (session == null) return false;
return session.mayLaunchUrl(uri, extras, otherLikelyBundles);
}
#Override
public void onServiceConnected(CustomTabsClient client) {
mClient = client;
mClient.warmup(0L);
if (mConnectionCallback != null) mConnectionCallback.onCustomTabsConnected();
}
#Override
public void onServiceDisconnected() {
mClient = null;
mCustomTabsSession = null;
if (mConnectionCallback != null) mConnectionCallback.onCustomTabsDisconnected();
}
/**
* A Callback for when the service is connected or disconnected. Use those callbacks to
* handle UI changes when the service is connected or disconnected.
*/
public interface ConnectionCallback {
/**
* Called when the service is connected.
*/
void onCustomTabsConnected();
/**
* Called when the service is disconnected.
*/
void onCustomTabsDisconnected();
}
/**
* To be used as a fallback to open the Uri when Custom Tabs is not available.
*/
public interface CustomTabFallback {
/**
* #param activity The Activity that wants to open the Uri.
* #param uri The uri to be opened by the fallback.
*/
void openUri(Activity activity, Uri uri);
}
}
CustomTabsHelper.java
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.net.Uri;
import android.text.TextUtils;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
/**
* Helper class for Custom Tabs.
*/
public class CustomTabsHelper {
private static final String TAG = "CustomTabsHelper";
static final String STABLE_PACKAGE = "com.android.chrome";
static final String BETA_PACKAGE = "com.chrome.beta";
static final String DEV_PACKAGE = "com.chrome.dev";
static final String LOCAL_PACKAGE = "com.google.android.apps.chrome";
private static final String EXTRA_CUSTOM_TABS_KEEP_ALIVE =
"android.support.customtabs.extra.KEEP_ALIVE";
private static final String ACTION_CUSTOM_TABS_CONNECTION =
"android.support.customtabs.action.CustomTabsService";
private static String sPackageNameToUse;
private CustomTabsHelper() {}
public static void addKeepAliveExtra(Context context, Intent intent) {
Intent keepAliveIntent = new Intent().setClassName(
context.getPackageName(), KeepAliveService.class.getCanonicalName());
intent.putExtra(EXTRA_CUSTOM_TABS_KEEP_ALIVE, keepAliveIntent);
}
/**
* Goes through all apps that handle VIEW intents and have a warmup service. Picks
* the one chosen by the user if there is one, otherwise makes a best effort to return a
* valid package name.
*
* This is <strong>not</strong> threadsafe.
*
* #param context {#link Context} to use for accessing {#link PackageManager}.
* #return The package name recommended to use for connecting to custom tabs related components.
*/
public static String getPackageNameToUse(Context context) {
if (sPackageNameToUse != null) return sPackageNameToUse;
PackageManager pm = context.getPackageManager();
// Get default VIEW intent handler.
Intent activityIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.example.com"));
ResolveInfo defaultViewHandlerInfo = pm.resolveActivity(activityIntent, 0);
String defaultViewHandlerPackageName = null;
if (defaultViewHandlerInfo != null) {
defaultViewHandlerPackageName = defaultViewHandlerInfo.activityInfo.packageName;
}
// Get all apps that can handle VIEW intents.
List<ResolveInfo> resolvedActivityList = pm.queryIntentActivities(activityIntent, 0);
List<String> packagesSupportingCustomTabs = new ArrayList<>();
for (ResolveInfo info : resolvedActivityList) {
Intent serviceIntent = new Intent();
serviceIntent.setAction(ACTION_CUSTOM_TABS_CONNECTION);
serviceIntent.setPackage(info.activityInfo.packageName);
if (pm.resolveService(serviceIntent, 0) != null) {
packagesSupportingCustomTabs.add(info.activityInfo.packageName);
}
}
// Now packagesSupportingCustomTabs contains all apps that can handle both VIEW intents
// and service calls.
if (packagesSupportingCustomTabs.isEmpty()) {
sPackageNameToUse = null;
} else if (packagesSupportingCustomTabs.size() == 1) {
sPackageNameToUse = packagesSupportingCustomTabs.get(0);
} else if (!TextUtils.isEmpty(defaultViewHandlerPackageName)
&& !hasSpecializedHandlerIntents(context, activityIntent)
&& packagesSupportingCustomTabs.contains(defaultViewHandlerPackageName)) {
sPackageNameToUse = defaultViewHandlerPackageName;
} else if (packagesSupportingCustomTabs.contains(STABLE_PACKAGE)) {
sPackageNameToUse = STABLE_PACKAGE;
} else if (packagesSupportingCustomTabs.contains(BETA_PACKAGE)) {
sPackageNameToUse = BETA_PACKAGE;
} else if (packagesSupportingCustomTabs.contains(DEV_PACKAGE)) {
sPackageNameToUse = DEV_PACKAGE;
} else if (packagesSupportingCustomTabs.contains(LOCAL_PACKAGE)) {
sPackageNameToUse = LOCAL_PACKAGE;
}
return sPackageNameToUse;
}
/**
* Used to check whether there is a specialized handler for a given intent.
* #param intent The intent to check with.
* #return Whether there is a specialized handler for the given intent.
*/
private static boolean hasSpecializedHandlerIntents(Context context, Intent intent) {
try {
PackageManager pm = context.getPackageManager();
List<ResolveInfo> handlers = pm.queryIntentActivities(
intent,
PackageManager.GET_RESOLVED_FILTER);
if (handlers == null || handlers.size() == 0) {
return false;
}
for (ResolveInfo resolveInfo : handlers) {
IntentFilter filter = resolveInfo.filter;
if (filter == null) continue;
if (filter.countDataAuthorities() == 0 || filter.countDataPaths() == 0) continue;
if (resolveInfo.activityInfo == null) continue;
return true;
}
} catch (RuntimeException e) {
Log.e(TAG, "Runtime exception while getting specialized handlers");
}
return false;
}
/**
* #return All possible chrome package names that provide custom tabs feature.
*/
public static String[] getPackages() {
return new String[]{"", STABLE_PACKAGE, BETA_PACKAGE, DEV_PACKAGE, LOCAL_PACKAGE};
}
}
ServiceConnection.java
import android.content.ComponentName;
import android.support.customtabs.CustomTabsClient;
import android.support.customtabs.CustomTabsServiceConnection;
import java.lang.ref.WeakReference;
/**
* Implementation for the CustomTabsServiceConnection that avoids leaking the
* ServiceConnectionCallback
*/
public class ServiceConnection extends CustomTabsServiceConnection {
// A weak reference to the ServiceConnectionCallback to avoid leaking it.
private WeakReference<ServiceConnectionCallback> mConnectionCallback;
public ServiceConnection(ServiceConnectionCallback connectionCallback) {
mConnectionCallback = new WeakReference<>(connectionCallback);
}
#Override
public void onCustomTabsServiceConnected(ComponentName name, CustomTabsClient client) {
ServiceConnectionCallback connectionCallback = mConnectionCallback.get();
if (connectionCallback != null) connectionCallback.onServiceConnected(client);
}
#Override
public void onServiceDisconnected(ComponentName name) {
ServiceConnectionCallback connectionCallback = mConnectionCallback.get();
if (connectionCallback != null) connectionCallback.onServiceDisconnected();
}
}
ServiceConnectionCallback.java
import android.support.customtabs.CustomTabsClient;
/**
* Callback for events when connecting and disconnecting from Custom Tabs Service.
*/
public interface ServiceConnectionCallback {
/**
* Called when the service is connected.
* #param client a CustomTabsClient
*/
void onServiceConnected(CustomTabsClient client);
/**
* Called when the service is disconnected.
*/
void onServiceDisconnected();
}
WebviewFallback.java
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
/**
* A Fallback that opens a Webview when Custom Tabs is not available
*/
public class WebviewFallback implements CustomTabActivityHelper.CustomTabFallback {
#Override
public void openUri(Activity activity, Uri uri) {
Intent intent = new Intent(activity, WebviewActivity.class);
intent.putExtra(WebviewActivity.EXTRA_URL, uri.toString());
activity.startActivity(intent);
}
}
By now, you should be able to open Chrome custom tab.
If found any issue with this, just let me know.

#Chintan Soni's answer is absolutely correct for Android SDK versions lower than 21.
For higher versions when querying activities that can handle the intent in getPackageNameToUse() function pass flag PackageManager.MATCH_ALL like this.
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1)
resolvedActivityList = pm.queryIntentActivities(activityIntent,
PackageManager.MATCH_ALL);
else
resolvedActivityList = pm.queryIntentActivities(activityIntent, 0);

add next string to tour code before WebSettings webSettings
webView.setWebViewClient(new WebViewClient());

Integrate Mobile Vision Barcode API into android app [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 7 years ago.
Improve this question
I am developing a BarcodeScanner app on android. Google has release the native Mobile Vision API link for android barcode.So i want to use the android native barcode API instead of any third party library.
So to sum up my problem :
1- How to integrate Barcode API into my Android App?
2- After integrated how to call the barcode function and get back the scan result ?
Note- A step to step guide will be helpful.
I integrate the code in my app successfully.I posted the answer and question so that it will be helpful to others. If any other ans it would be appreciated.Thanks in advanced..:)

Prerequisite:
• Android 4.2.2+
• Latest Android SDK
• Google Play Services 7.8+ (Rev. 26.0 in SDK)
• compile 'com.android.support:appcompat-v7:22.0.0'
• compile 'com.google.android.gms:play-services:7.8+'
Download the code sample code from this link,import the barcode-reader project in android studio. Add the google play services 7.8+ & add the mentioned support library in your app gradle. Now modified the BarcodeTrackerFactory.java and MultiTrackerActivity.java class.
BarcodeTrackerFactory.java
import android.app.Activity;
import android.content.Intent;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.Log;
import com.google.android.gms.samples.vision.face.multitracker.ui.camera.GraphicOverlay;
import com.google.android.gms.vision.MultiProcessor;
import com.google.android.gms.vision.Tracker;
import com.google.android.gms.vision.barcode.Barcode;
/**
* Factory for creating a tracker and associated graphic to be associated with a new barcode. The
* multi-processor uses this factory to create barcode trackers as needed -- one for each barcode.
*/
class BarcodeTrackerFactory implements MultiProcessor.Factory<Barcode> {
public Activity context;
private GraphicOverlay mGraphicOverlay;
BarcodeTrackerFactory(GraphicOverlay graphicOverlay) {
mGraphicOverlay = graphicOverlay;
}
BarcodeTrackerFactory(GraphicOverlay graphicOverlay ,Activity ctx) {
mGraphicOverlay = graphicOverlay;
this.context =ctx;
}
#Override
public Tracker<Barcode> create(Barcode barcode) {
BarcodeGraphic graphic = new BarcodeGraphic(mGraphicOverlay,context);
return new GraphicTracker<>(mGraphicOverlay, graphic);
}
}
/**
* Graphic instance for rendering barcode position, size, and ID within an associated graphic
* overlay view.
*/
class BarcodeGraphic extends TrackedGraphic<Barcode> {
private static final int COLOR_CHOICES[] = {
Color.BLUE,
Color.CYAN,
Color.GREEN
};
private static int mCurrentColorIndex = 0;
private Paint mRectPaint;
private Paint mTextPaint;
private volatile Barcode mBarcode;
private Activity context;
private boolean isFirstScandetaction=true;
BarcodeGraphic(GraphicOverlay overlay ,Activity context) {
super(overlay);
this.context=context;
mCurrentColorIndex = (mCurrentColorIndex + 1) % COLOR_CHOICES.length;
final int selectedColor = COLOR_CHOICES[mCurrentColorIndex];
mRectPaint = new Paint();
mRectPaint.setColor(selectedColor);
mRectPaint.setStyle(Paint.Style.STROKE);
mRectPaint.setStrokeWidth(4.0f);
mTextPaint = new Paint();
mTextPaint.setColor(selectedColor);
mTextPaint.setTextSize(36.0f);
}
/**
* Updates the barcode instance from the detection of the most recent frame. Invalidates the
* relevant portions of the overlay to trigger a redraw.
*/
void updateItem(Barcode barcode) {
mBarcode = barcode;
if (isFirstScandetaction) {
postInvalidate();
if (null != mBarcode) {
isFirstScandetaction = false;
Intent intent = new Intent();
intent.putExtra("SCAN_RESULT", barcode.rawValue.toString());
intent.putExtra("SCAN_RESULT_FORMAT",String.valueOf( barcode.format));
context.setResult(Activity.RESULT_OK, intent);
context.finish();
}
}
}
/**
* Draws the barcode annotations for position, size, and raw value on the supplied canvas.
*/
#Override
public void draw(Canvas canvas) {
Barcode barcode = mBarcode;
if (barcode == null) {
return;
}
// Draws the bounding box around the barcode.
RectF rect = new RectF(barcode.getBoundingBox());
rect.left = translateX(rect.left);
rect.top = translateY(rect.top);
rect.right = translateX(rect.right);
rect.bottom = translateY(rect.bottom);
canvas.drawRect(rect, mRectPaint);
// Draws a label at the bottom of the barcode indicate the barcode value that was detected.
canvas.drawText(barcode.rawValue, rect.left, rect.bottom, mTextPaint);
Log.v("On Draw", "called");
}
}
MultiTrackerActivity.java
import java.io.IOException;
import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GoogleApiAvailability;
import com.google.android.gms.samples.vision.face.multitracker.ui.camera.CameraSourcePreview;
import com.google.android.gms.samples.vision.face.multitracker.ui.camera.GraphicOverlay;
import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.MultiProcessor;
import com.google.android.gms.vision.barcode.BarcodeDetector;
/**
* Activity for the multi-tracker app. This app detects faces and barcodes with the rear facing
* camera, and draws overlay graphics to indicate the position, size, and ID of each face and
* barcode.
*/
public final class MultiTrackerActivity extends AppCompatActivity {
private static final String TAG = "MultiTracker";
private static final int RC_HANDLE_GMS = 9001;
// permission request codes need to be < 256
private static final int RC_HANDLE_CAMERA_PERM = 2;
private CameraSource mCameraSource = null;
private CameraSourcePreview mPreview;
private GraphicOverlay mGraphicOverlay;
/**
* Initializes the UI and creates the detector pipeline.
*/
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
mPreview = (CameraSourcePreview) findViewById(R.id.preview);
mGraphicOverlay = (GraphicOverlay) findViewById(R.id.faceOverlay);
// Check for the camera permission before accessing the camera. If the
// permission is not granted yet, request permission.
int rc = ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA);
if (rc == PackageManager.PERMISSION_GRANTED) {
createCameraSource();
} else {
requestCameraPermission();
}
}
/**
* Handles the requesting of the camera permission. This includes
* showing a "Snackbar" message of why the permission is needed then
* sending the request.
*/
private void requestCameraPermission() {
Log.w(TAG, "Camera permission is not granted. Requesting permission");
final String[] permissions = new String[]{Manifest.permission.CAMERA};
if (!ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.CAMERA)) {
ActivityCompat.requestPermissions(this, permissions, RC_HANDLE_CAMERA_PERM);
return;
}
final Activity thisActivity = this;
View.OnClickListener listener = new View.OnClickListener() {
#Override
public void onClick(View view) {
ActivityCompat.requestPermissions(thisActivity, permissions,
RC_HANDLE_CAMERA_PERM);
}
};
Snackbar.make(mGraphicOverlay, R.string.permission_camera_rationale,
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, listener)
.show();
}
/**
* Creates and starts the camera. Note that this uses a higher resolution in comparison
* to other detection examples to enable the barcode detector to detect small barcodes
* at long distances.
*/
private void createCameraSource() {
Context context = getApplicationContext();
// A barcode detector is created to track barcodes. An associated multi-processor instance
// is set to receive the barcode detection results, track the barcodes, and maintain
// graphics for each barcode on screen. The factory is used by the multi-processor to
// create a separate tracker instance for each barcode.
BarcodeDetector barcodeDetector = new BarcodeDetector.Builder(context).build();
BarcodeTrackerFactory barcodeFactory = new BarcodeTrackerFactory(mGraphicOverlay,this);
barcodeDetector.setProcessor(
new MultiProcessor.Builder<>(barcodeFactory).build());
if (!barcodeDetector.isOperational()) {
// Note: The first time that an app using the barcode or face API is installed on a
// device, GMS will download a native libraries to the device in order to do detection.
// Usually this completes before the app is run for the first time. But if that
// download has not yet completed, then the above call will not detect any barcodes
// and/or faces.
//
// isOperational() can be used to check if the required native libraries are currently
// available. The detectors will automatically become operational once the library
// downloads complete on device.
Log.w(TAG, "Detector dependencies are not yet available.");
}
// Creates and starts the camera. Note that this uses a higher resolution in comparison
// to other detection examples to enable the barcode detector to detect small barcodes
// at long distances.
mCameraSource = new CameraSource.Builder(getApplicationContext(), barcodeDetector)
.setFacing(CameraSource.CAMERA_FACING_BACK)
.setRequestedPreviewSize(1600, 1024)
.setRequestedFps(15.0f)
.build();
}
/**
* Restarts the camera.
*/
#Override
protected void onResume() {
super.onResume();
startCameraSource();
}
/**
* Stops the camera.
*/
#Override
protected void onPause() {
super.onPause();
mPreview.stop();
}
/**
* Releases the resources associated with the camera source, the associated detectors, and the
* rest of the processing pipeline.
*/
#Override
protected void onDestroy() {
super.onDestroy();
if (mCameraSource != null) {
mCameraSource.release();
}
}
/**
* Callback for the result from requesting permissions. This method
* is invoked for every call on {#link #requestPermissions(String[], int)}.
* <p>
* <strong>Note:</strong> It is possible that the permissions request interaction
* with the user is interrupted. In this case you will receive empty permissions
* and results arrays which should be treated as a cancellation.
* </p>
*
* #param requestCode The request code passed in {#link #requestPermissions(String[], int)}.
* #param permissions The requested permissions. Never null.
* #param grantResults The grant results for the corresponding permissions
* which is either {#link PackageManager#PERMISSION_GRANTED}
* or {#link PackageManager#PERMISSION_DENIED}. Never null.
* #see #requestPermissions(String[], int)
*/
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
if (requestCode != RC_HANDLE_CAMERA_PERM) {
Log.d(TAG, "Got unexpected permission result: " + requestCode);
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
return;
}
if (grantResults.length != 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Log.d(TAG, "Camera permission granted - initialize the camera source");
// we have permission, so create the camerasource
createCameraSource();
return;
}
Log.e(TAG, "Permission not granted: results len = " + grantResults.length +
" Result code = " + (grantResults.length > 0 ? grantResults[0] : "(empty)"));
DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Multitracker sample")
.setMessage(R.string.no_camera_permission)
.setPositiveButton(R.string.ok, listener)
.show();
}
/**
* Starts or restarts the camera source, if it exists. If the camera source doesn't exist yet
* (e.g., because onResume was called before the camera source was created), this will be called
* again when the camera source is created.
*/
private void startCameraSource() {
// check that the device has play services available.
int code = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(
getApplicationContext());
if (code != ConnectionResult.SUCCESS) {
Dialog dlg =
GoogleApiAvailability.getInstance().getErrorDialog(this, code, RC_HANDLE_GMS);
dlg.show();
}
if (mCameraSource != null) {
try {
mPreview.start(mCameraSource, mGraphicOverlay);
} catch (IOException e) {
Log.e(TAG, "Unable to start camera source.", e);
mCameraSource.release();
mCameraSource = null;
}
}
}
}
Now to call the scan code and recieve the result-
BarCodeReader.java
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
public class BarCodeReader extends FragmentActivity {
String QR_CODE = "256";
private Button btnscan;
#Override
protected void onCreate(Bundle bundle) {
super.onCreate(bundle);
setContentView(R.layout.scanlayout);
btnscan = (Button) findViewById(R.id.scanbtn);
btnscan.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(BarCodeReader.this,
MultiTrackerActivity.class);
startActivityForResult(intent, 0);
}
});
}
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
if (requestCode == 0) {
if (resultCode == RESULT_OK) {
String contents = intent.getStringExtra("SCAN_RESULT");
String format = intent.getStringExtra("SCAN_RESULT_FORMAT");
if (format.equals(QR_CODE)) {
Toast.makeText(
BarCodeReader.this,
"content is : " + contents + " \n Format is: "
+ format, Toast.LENGTH_LONG).show();
} else {
Toast.makeText(BarCodeReader.this, "wrong format",
Toast.LENGTH_LONG).show();
}
} else if (resultCode == RESULT_CANCELED) {
// To Handle cancel
Log.i("App", "Scan unsuccessful");
}
}
}
}