Develop Reference

Difference in Context for Activity and Fragment?

I am trying to integrate some code and one of the lines I have is:
mPreview = new CameraPreview(this, mCamera, previewCb, autoFocusCB);
When I have it in an Activity, there is no error. When I put it in my Fragment, I get this error:
Expected:android.content.context
Actual:this (com.xxx.ScanFragment)
This is the CameraPreview method
public CameraPreview(Context context, Camera camera,
PreviewCallback previewCb,
AutoFocusCallback autoFocusCb)
As I said, no error when this was in the activity file, so I assume the issue is some difference in what "context" is between Activities and Fragments?
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.FrameLayout;
import android.widget.TextView;
import com.parse.ParseUser;
import net.sourceforge.zbar.Config;
import net.sourceforge.zbar.Image;
import net.sourceforge.zbar.ImageScanner;
import net.sourceforge.zbar.Symbol;
import net.sourceforge.zbar.SymbolSet;
/**
* Created by Jakub on 7/23/2014.
*/
public class Pay extends Fragment {
private Button scanBtn;
private TextView formatTxt, contentTxt;
private Camera mCamera;
private CameraPreview mPreview;
private Handler autoFocusHandler;
TextView scanText;
Button scanButton;
ImageScanner scanner;
private boolean barcodeScanned = false;
private boolean previewing = true;
static {
System.loadLibrary("iconv");
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_pay, container, false);
return rootView;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
autoFocusHandler = new Handler();
mCamera = getCameraInstance();
/* Instance barcode scanner */
scanner = new ImageScanner();
scanner.setConfig(0, Config.X_DENSITY, 3);
scanner.setConfig(0, Config.Y_DENSITY, 3);
mPreview = new CameraPreview(getActivity(), mCamera, previewCb, autoFocusCB);
FrameLayout preview = (FrameLayout)getActivity().findViewById(R.id.cameraPreview);
Log.d(Payspot.TAG,"This is the string:" + preview.toString());
preview.addView(mPreview);
scanText = (TextView)getActivity().findViewById(R.id.scanText);
scanButton = (Button)getActivity().findViewById(R.id.ScanButton);
scanButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
if (barcodeScanned) {
barcodeScanned = false;
scanText.setText("Scanning...");
mCamera.setPreviewCallback(previewCb);
mCamera.startPreview();
previewing = true;
mCamera.autoFocus(autoFocusCB);
}
}
});
}
public void onPause() {
super.onPause();
releaseCamera();
}
/** 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){
}
return c;
}
private void releaseCamera() {
if (mCamera != null) {
previewing = false;
mCamera.setPreviewCallback(null);
mCamera.release();
mCamera = null;
}
}
private Runnable doAutoFocus = new Runnable() {
public void run() {
if (previewing)
mCamera.autoFocus(autoFocusCB);
}
};
Camera.PreviewCallback previewCb = new Camera.PreviewCallback() {
public void onPreviewFrame(byte[] data, Camera camera) {
Camera.Parameters parameters = camera.getParameters();
Camera.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) {
scanText.setText("barcode result " + sym.getData());
barcodeScanned = true;
}
}
}
};
// Mimic continuous auto-focusing
Camera.AutoFocusCallback autoFocusCB = new Camera.AutoFocusCallback() {
public void onAutoFocus(boolean success, Camera camera) {
autoFocusHandler.postDelayed(doAutoFocus, 1000);
}
};
}

Activity extends Context, but Fragments do not. This is why you can pass it this for a context parameter. So the error message sees your ScanFragment as a parameter for Context which does not work. Each Fragment is associated with an Activity's fragment. You can either use getActivity() or getActivity().getApplicationContext() to receive a valid context to use in these situations.
Your new code would be:
mPreview = new CameraPreview(getActivity(), mCamera, previewCb, autoFocusCB);

In fragment you must call getActivity() method to get the context. Because fragment must be associated with an activity and has activity context (activity extends Context).

Get buttons to open custom dialog with camera preview in surface view

I have two buttons that need to open a custom dialog that has a surface view that's supposed to hold a camera preview. I need to not have the default camera controls, just the preview itself, behind another included layout that's holding buttons.
Here's the code for my buttons:
topeyebtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg3) {
//Starting a new Intent
Intent topClick = new Intent(Intent.ACTION_VIEW, Uri.parse("http://funnmag.com"));
// starting new activity
startActivity(topClick);
}});
And here's the code for my surface view and camera preview:
package com.adanawtn.FunnMagViewerWindow;
import java.io.IOException;
import android.app.Activity;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.ViewGroup.LayoutParams;
public class camerapreview extends Activity {
private SurfaceView surface_view;
private Camera mCamera;
SurfaceHolder.Callback sh_ob = null;
SurfaceHolder surface_holder = null;
SurfaceHolder.Callback sh_callback = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFormat(PixelFormat.TRANSLUCENT);
surface_view = new SurfaceView(getApplicationContext());
addContentView(surface_view, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
if (surface_holder == null) {
surface_holder = surface_view.getHolder();
}
sh_callback = my_callback();
surface_holder.addCallback(sh_callback);
}
SurfaceHolder.Callback my_callback() {
SurfaceHolder.Callback ob1 = new SurfaceHolder.Callback() {
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera = Camera.open();
try {
mCamera.setPreviewDisplay(holder);
} catch (IOException exception) {
mCamera.release();
mCamera = null;
}
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
mCamera.startPreview();
}
};
return ob1;
}
}

Android camera app gives error on back and home button

My Application gives error "Unfortunately PhotoComment has stopped" when I am pressing back or home button. But when I am reopening app from task manager it works.
this is my mainactivity.java
package com.cameratag;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Date;
import java.text.SimpleDateFormat;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.FrameLayout;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.TextView;
public class MainActivity extends Activity{
private CameraSurfaceView cameraView;
private ImageView imageResult;
private ImageView imageResult2;
private FrameLayout framenew;
private TextView snapPhoto;
private boolean takePicture = true;
private Bitmap image = null;
private String lastPreviewImgPath = "";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setupcamera();
}
public void setupcamera(){
cameraView = new CameraSurfaceView(getApplicationContext());
imageResult = new ImageView(getApplicationContext());
imageResult.setBackgroundColor(Color.GRAY);
framenew = (FrameLayout) findViewById(R.id.frame);
snapPhoto = (TextView) findViewById(R.id.textView1);
framenew.addView(imageResult);
framenew.addView(cameraView);
}
public void captureHandler(View view){
if(takePicture){
cameraView.capture(jpegHandler);
}
else{
takePicture = true;
cameraView.preview();
framenew.bringChildToFront(cameraView);
imageResult.setImageBitmap(null);
snapPhoto.setText("Capture");
}
}
public void zoomMinusHandler(View view){
cameraView.zoomMinus();
}
public void zoomPilusHandler(View view){
cameraView.zoomPilus();
}
public Camera.PictureCallback jpegHandler = new Camera.PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
// TODO Auto-generated method stub
image = BitmapFactory.decodeByteArray(data, 0, data.length);
imageResult.setImageBitmap(image);
imageResult2 = imageResult;
LayoutParams params = imageResult.getLayoutParams();
params.width = framenew.getWidth();
params.height = framenew.getHeight();
imageResult2.setLayoutParams(params);
//framenew.bringChildToFront(imageResult);
//snapPhoto.setText("Take Picture");
//takePicture = false;
File directory = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "NNCam");
if (!directory.exists()) {
if (!directory.mkdirs()) {
//Log.e(TAG, "Failed to create storage directory.");
}
}
String timeStamp = new SimpleDateFormat("yyyMMdd_HHmmss").format(new Date(System.currentTimeMillis()));
String filename = "/IMG_" + timeStamp + ".jpg";
if(image!=null){
saveImage(directory.getPath(),filename,image);
cameraView.preview();
}
}
};
public void saveImage(String path, String imgname, Bitmap image){
try{
FileOutputStream fos = new FileOutputStream(path+imgname);
BufferedOutputStream stream = new BufferedOutputStream(fos);
image.compress(CompressFormat.JPEG, 100, stream);
stream.flush();
stream.close();
}
catch(FileNotFoundException e){
}
catch(IOException e){
}
lastPreviewImgPath = path+imgname;
Bitmap bitmap = BitmapFactory.decodeFile(lastPreviewImgPath);
ImageView myImageView = (ImageView)findViewById(R.id.lastPreview);
myImageView.setImageBitmap(bitmap);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
cameraView.release();
}
#Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
cameraView.reconnect();
}
#Override
public void onPause() {
super.onPause();
cameraView.release();
}
}
and this is surfaceview class
package com.cameratag;
import java.io.IOException;
import java.util.List;
import android.content.Context;
import android.content.res.Configuration;
import android.hardware.Camera;
import android.view.Display;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.WindowManager;
public class CameraSurfaceView extends SurfaceView implements SurfaceHolder.Callback{
private Context context;
private SurfaceHolder mHolder;
public Camera camera = null;
public int zoomValue = 0;
public CameraSurfaceView(Context context) {
super(context);
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
// TODO Auto-generated constructor stub
}
#Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
// TODO Auto-generated method stub
Camera.Parameters parameters = camera.getParameters();
List<Camera.Size> sizes = parameters.getSupportedPictureSizes();
Camera.Size cs = sizes.get(0);
List<Camera.Size> sizes2 = parameters.getSupportedPreviewSizes();
Camera.Size cs2 = sizes2.get(0);
parameters.setPreviewSize(cs2.width, cs2.height);
parameters.setPictureSize(cs.width, cs.height);
camera.setParameters(parameters);
camera.startPreview();
}
#Override
public void surfaceCreated(SurfaceHolder arg0) {
// TODO Auto-generated method stub
camera = Camera.open();
try {
camera.setPreviewDisplay(mHolder);
} catch (IOException e) {
// TODO Auto-generated catch block
//e.printStackTrace();
}
int rrr = 0;
Display display = ((WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int rotation = display.getRotation();
if(rotation==0)rrr=90;
else if(rotation==1)rrr=0;
else if(rotation==3)rrr=180;
else rrr=270;
camera.setDisplayOrientation(rrr);
}
#Override
public void surfaceDestroyed(SurfaceHolder arg0) {
// TODO Auto-generated method stub
camera.stopPreview();
camera = null;
}
public void capture(Camera.PictureCallback jpegHandler){
camera.takePicture(null, null, jpegHandler);
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
int rrr = 0;
Display display = ((WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int rotation = display.getRotation();
if(rotation==0)rrr=90;
else if(rotation==1)rrr=0;
else if(rotation==3)rrr=180;
else rrr=270;
//camera.stopPreview();
camera.setDisplayOrientation(rrr);
//camera.startPreview();
}
public void preview(){
camera.startPreview();
}
public void reconnect(){
try {
camera.reconnect();
} catch (IOException e) {
// TODO Auto-generated catch block
//e.printStackTrace();
}
}
public void zoomMinus() {
Camera.Parameters parameters = camera.getParameters();
// TODO Auto-generated method stub
if(parameters.isZoomSupported()){
if(zoomValue>0){
zoomValue-=2;
parameters.setZoom(zoomValue);
if(parameters.isSmoothZoomSupported()){
camera.startSmoothZoom(zoomValue);
}
else{
camera.setParameters(parameters);
}
}
}
}
public void zoomPilus() {
Camera.Parameters parameters = camera.getParameters();
// TODO Auto-generated method stub
if(parameters.isZoomSupported()){
if(zoomValue<parameters.getMaxZoom()){
zoomValue+=2;
parameters.setZoom(zoomValue);
if(parameters.isSmoothZoomSupported()){
camera.startSmoothZoom(zoomValue);
}
else{
camera.setParameters(parameters);
}
}
}
}
public void release() {
// TODO Auto-generated method stub
camera.setPreviewCallback(null);
camera.stopPreview();
camera.release();
}
}
Please help.

#Override
protected void onPause() {
super.onPause();
// if (inPreview) {
// mCamera.stopPreview();
// }
// mCamera.release();
// mCamera = null;
// inPreview = false;
mCamera.setPreviewCallback(null);
super.onPause();
// mCamera.stopPreview();
}

I was having a similar issue, the trick is to also setup the camera inside of onResume().
The issue was that the app does not call onCreate() every time you go to an activity with the back button, sometimes it simply pauses the activity. onResume() is called whenever the activity returns to the foreground and is a more reliable place to set up the camera.
#Override
protected void onResume()
{
super.onResume();
if( camera == null )
{
camera = Camera.open();
}
}

try to put your release code in try catch block
try{
if (camera != null){
camera.setPreviewCallback(null);
camera.stopPreview();
camera.release();
}
}

I have found the solution for my own. You only need to change surfaceDestroyed method to this.
#Override
public void surfaceDestroyed(SurfaceHolder arg0) {
// TODO Auto-generated method stub
try{
camera.stopPreview();
camera.release();
camera = null;
}
catch(NullPointerException e){
//e.printStackTrace();
}
}
and on onRestoreInstanceState to this.
#Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
cameraView = null;
setupcamera();
//cameraView.reconnect();
}

Camera preview stops on activity restart

I made a camera preview app for android and everything works fine even when I press the power button to make device asleep, and waking it up again. But when my activity goes to background (like pressing home button) and then it comes to foreground again the program stops.
This is my activity code:
package com.example.campreview;
import com.example.campreview.CameraPreview;
import com.example.campreview.R;
import android.graphics.ImageFormat;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PreviewCallback;
import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.view.Menu;
import android.view.View;
public class ScanActivity extends Activity {
private CameraPreview CamPrev = null;
private FrameLayout PreviewFrm;
private Camera cam = null;
private Handler atfcs;
private ImageScanner scnr;
private boolean hascam = false;
private boolean prvng = true;
private boolean paused = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scan);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
PreviewFrm = (FrameLayout)findViewById(R.id.PreviewFrm);
StartCamera();
if (cam != null) {
hascam = true;
atfcs = new Handler();
CamPrev = new CameraPreview(this, cam, PreviewCB, AutoFocusCB);
PreviewFrm.addView(CamPrev);
}
}
#Override
public void onPause() {
ReleaseCamera();
paused = true;
super.onPause();
}
#Override
public void onResume() {
super.onResume();
if (paused) StartPreview();
}
private boolean StartCamera() {
boolean r = true;
if (cam == null) {
try {
cam = Camera.open();
} catch (Exception e) {
cam = null;
r = false;
}
if (cam != null) {
try {
Camera.Parameters p = cam.getParameters();
if (p.getSupportedFocusModes().contains(Camera.Parameters.FOCUS_MODE_AUTO))
p.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
if (p.getSupportedFlashModes().contains(Camera.Parameters.FLASH_MODE_OFF))
p.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
if (p.getSupportedPreviewFormats().contains(ImageFormat.NV21))
p.setPreviewFormat(ImageFormat.NV21);
Camera.Size s = null;
int a = 0, b;
for (Camera.Size z : p.getSupportedPreviewSizes()) {
b = z.width * z.height;
if (Math.abs(b - 307200) < Math.abs(a - 307200)) { //640x480 is the best
s = z;
a = b;
}
}
if (a != 0) p.setPreviewSize(s.width, s.height);
cam.setParameters(p);
cam.setDisplayOrientation(90);
if (CamPrev != null) cam.setPreviewDisplay(CamPrev.getHolder());
} catch (Exception e) {
r = false;
cam.release();
cam = null;
}
}
}
return r;
}
private void ReleaseCamera() {
if (cam != null) {
StopPreview();
cam.release();
cam = null;
}
}
public void StartPreview() {
if ((!prvng) & hascam) {
if (StartCamera()) {
cam.setPreviewCallback(PreviewCB);
cam.startPreview();
cam.autoFocus(AutoFocusCB);
prvng = true;
}
}
}
public void StopPreview() {
if (prvng) {
cam.stopPreview();
cam.setPreviewCallback(null);
prvng = false;
}
}
private Runnable DoAutoFocus = new Runnable() {
public void run() {
if (prvng) cam.autoFocus(AutoFocusCB);
}
};
AutoFocusCallback AutoFocusCB = new AutoFocusCallback() {
public void onAutoFocus(boolean success, Camera camera) {
atfcs.postDelayed(DoAutoFocus, 1000);
}
};
PreviewCallback PreviewCB = new PreviewCallback() {
public void onPreviewFrame(byte[] data, Camera camera) {
//
}
};
}
And this is the preview code:
package com.example.campreview;
import java.io.IOException;
import android.view.SurfaceView;
import android.view.SurfaceHolder;
import android.content.Context;
import android.hardware.Camera;
import android.hardware.Camera.PreviewCallback;
import android.hardware.Camera.AutoFocusCallback;
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder hldr;
private Camera cam;
private PreviewCallback pcb;
private AutoFocusCallback afcb;
public CameraPreview(Context context, Camera camera, PreviewCallback previewCb, AutoFocusCallback autoFocusCb) {
super(context);
cam = camera;
pcb = previewCb;
afcb = autoFocusCb;
hldr = getHolder();
hldr.addCallback(this);
//hldr.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
try {
cam.setPreviewDisplay(holder);
} catch (IOException e) {
// No Code
}
}
public void surfaceDestroyed(SurfaceHolder holder) {}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
if (hldr.getSurface() == null) return;
try {
cam.stopPreview();
} catch (Exception e){
// No Code
}
try {
cam.setPreviewDisplay(hldr);
cam.setPreviewCallback(pcb);
cam.startPreview();
cam.autoFocus(afcb);
} catch (Exception e) {
// No Code
}
}
}
Is there any idea how can I solve this problem?

I found the problem. It seems the SurfaceView that is made in program destroys on activity stop. So I replaced it with a SurfaceView in my layout.
package com.example.campreview;
import com.example.campreview.R;
import java.io.IOException;
import android.graphics.ImageFormat;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PreviewCallback;
import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
public class ScanActivity extends Activity implements OnClickListener {
private SurfaceView PreviewSfc;
private Camera cam = null;
private Handler atfcs;
private boolean hascam = false;
private boolean validdisplay = false;
private boolean prvng = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_scan);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
PreviewSfc = (SurfaceView)findViewById(R.id.PreviewSfc);
PreviewSfc.getHolder().addCallback(SurfaceCB);
//PreviewSfc.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
StartCamera();
if (cam != null) {
hascam = true;
atfcs = new Handler();
}
}
#Override
public void onPause() {
ReleaseCamera();
super.onPause();
}
#Override
public void onResume() {
super.onResume();
StartPreview();
}
private boolean StartCamera() {
boolean r = true;
if (cam == null) {
try {
cam = Camera.open();
} catch (Exception e) {
cam = null;
r = false;
}
if (cam != null) {
try {
Camera.Parameters p = cam.getParameters();
if (p.getSupportedFocusModes().contains(Camera.Parameters.FOCUS_MODE_AUTO))
p.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
if (p.getSupportedFlashModes().contains(Camera.Parameters.FLASH_MODE_OFF))
p.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
if (p.getSupportedPreviewFormats().contains(ImageFormat.NV21))
p.setPreviewFormat(ImageFormat.NV21);
Camera.Size s = null;
int a = 0, b;
for (Camera.Size z : p.getSupportedPreviewSizes()) {
b = z.width * z.height;
if (Math.abs(b - 307200) < Math.abs(a - 307200)) { //640x480 is the best
s = z;
a = b;
}
}
if (a != 0) p.setPreviewSize(s.width, s.height);
cam.setParameters(p);
cam.setDisplayOrientation(90);
if (validdisplay) cam.setPreviewDisplay(PreviewSfc.getHolder());
} catch (Exception e) {
r = false;
cam.release();
cam = null;
}
}
}
//if (!r) Error message that failed to start camera
return r;
}
private void ReleaseCamera() {
if (cam != null) {
StopPreview();
cam.release();
cam = null;
}
}
public void StartPreview() {
if ((!prvng) & (hascam) & (validdisplay)) {
if (StartCamera()) {
cam.setPreviewCallback(PreviewCB);
cam.startPreview();
cam.autoFocus(AutoFocusCB);
prvng = true;
}
}
}
public void StopPreview() {
if (prvng) {
cam.stopPreview();
cam.setPreviewCallback(null);
prvng = false;
}
}
private Runnable DoAutoFocus = new Runnable() {
public void run() {
if (prvng) cam.autoFocus(AutoFocusCB);
}
};
AutoFocusCallback AutoFocusCB = new AutoFocusCallback() {
public void onAutoFocus(boolean success, Camera camera) {
atfcs.postDelayed(DoAutoFocus, 1000);
}
};
PreviewCallback PreviewCB = new PreviewCallback() {
public void onPreviewFrame(byte[] data, Camera camera) {
//
}
};
SurfaceHolder.Callback SurfaceCB = new SurfaceHolder.Callback() {
public void surfaceCreated(SurfaceHolder holder) {
if (cam != null) {
try {
cam.setPreviewDisplay(holder);
} catch (IOException e) {
// No Code
}
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
validdisplay = true;
StartPreview();
}
public void surfaceDestroyed(SurfaceHolder holder) {
validdisplay = false;
}
};
}

How to record video from background of application : Android

I am developing an application which will be able to record video from background of application by using Service.
Problem description :
In my application recording will be scheduled. If user want to record video from 1 PM to 3 PM, he will schedule the task and can exit from application. Application will automatically start recording at 1PM to 3PM.
What I did yet :
I googled about my query but didn't get solution. Many articles say that it is not possible. But in Google Play there are some applications (for eg MyCar Recorder) which can record video from background of application.
I got an article about same but its not working.
What is the way to implement this functionality?

1- I have created a activity to start service like this:
package com.android.camerarecorder;
import android.app.Activity;
import android.content.Intent;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
public class CameraRecorder extends Activity implements SurfaceHolder.Callback {
private static final String TAG = "Recorder";
public static SurfaceView mSurfaceView;
public static SurfaceHolder mSurfaceHolder;
public static Camera mCamera ;
public static boolean mPreviewRunning;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mSurfaceView = (SurfaceView) findViewById(R.id.surfaceView1);
mSurfaceHolder = mSurfaceView.getHolder();
mSurfaceHolder.addCallback(this);
mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
Button btnStart = (Button) findViewById(R.id.StartService);
btnStart.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent intent = new Intent(CameraRecorder.this, RecorderService.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startService(intent);
finish();
}
});
Button btnStop = (Button) findViewById(R.id.StopService);
btnStop.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
stopService(new Intent(CameraRecorder.this, RecorderService.class));
}
});
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
}
}
2 - Now I have created a service to record the video in background like this:
package com.android.camerarecorder;
import java.io.IOException;
import java.util.List;
import android.app.Service;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.hardware.Camera.Size;
import android.media.MediaRecorder;
import android.os.IBinder;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.Toast;
public class RecorderService extends Service {
private static final String TAG = "RecorderService";
private SurfaceView mSurfaceView;
private SurfaceHolder mSurfaceHolder;
private static Camera mServiceCamera;
private boolean mRecordingStatus;
private MediaRecorder mMediaRecorder;
#Override
public void onCreate() {
mRecordingStatus = false;
//mServiceCamera = CameraRecorder.mCamera;
mServiceCamera = Camera.open(1);
mSurfaceView = CameraRecorder.mSurfaceView;
mSurfaceHolder = CameraRecorder.mSurfaceHolder;
super.onCreate();
if (mRecordingStatus == false)
startRecording();
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onDestroy() {
stopRecording();
mRecordingStatus = false;
super.onDestroy();
}
public boolean startRecording(){
try {
Toast.makeText(getBaseContext(), "Recording Started", Toast.LENGTH_SHORT).show();
//mServiceCamera = Camera.open();
Camera.Parameters params = mServiceCamera.getParameters();
mServiceCamera.setParameters(params);
Camera.Parameters p = mServiceCamera.getParameters();
final List<Size> listSize = p.getSupportedPreviewSizes();
Size mPreviewSize = listSize.get(2);
Log.v(TAG, "use: width = " + mPreviewSize.width
+ " height = " + mPreviewSize.height);
p.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
p.setPreviewFormat(PixelFormat.YCbCr_420_SP);
mServiceCamera.setParameters(p);
try {
mServiceCamera.setPreviewDisplay(mSurfaceHolder);
mServiceCamera.startPreview();
}
catch (IOException e) {
Log.e(TAG, e.getMessage());
e.printStackTrace();
}
mServiceCamera.unlock();
mMediaRecorder = new MediaRecorder();
mMediaRecorder.setCamera(mServiceCamera);
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT);
mMediaRecorder.setOutputFile("/sdcard/video.mp4");
mMediaRecorder.setVideoFrameRate(30);
mMediaRecorder.setVideoSize(mPreviewSize.width, mPreviewSize.height);
mMediaRecorder.setPreviewDisplay(mSurfaceHolder.getSurface());
mMediaRecorder.prepare();
mMediaRecorder.start();
mRecordingStatus = true;
return true;
} catch (IllegalStateException e) {
Log.d(TAG, e.getMessage());
e.printStackTrace();
return false;
} catch (IOException e) {
Log.d(TAG, e.getMessage());
e.printStackTrace();
return false;
}
}
public void stopRecording() {
Toast.makeText(getBaseContext(), "Recording Stopped", Toast.LENGTH_SHORT).show();
try {
mServiceCamera.reconnect();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mMediaRecorder.stop();
mMediaRecorder.reset();
mServiceCamera.stopPreview();
mMediaRecorder.release();
mServiceCamera.release();
mServiceCamera = null;
}
}
It will create a file video.mp4 in your sd card. you may change the code for adding more functionality but the basic functionality is achieved through this code i.e. record video in background.
NOTE: I have started the service through button click in activity but you can start it through any other way also like broadcastreceiver etc.

Yes, you can record the background video like this:
First, create a video app using service. Do not set its view so that it will not be visible.
If you are doing it in service then that is better because...
Second, you can use the AlarmManager for setting the alarm of particular time and then at that time, by using intent, start your service again. For stopping your app you can use AlarmManager, as well.