Develop Reference

Detect Android device is foldable?

I'm working on a project that needs to distinguish a device type at startup, so whether it's a phone, tablet or foldable. I can distinguish between phone and tablet but is there a way to detect whether an android device is a foldable?

Check the link --> https://developer.android.com/
It seems that these is no particular API or configuration for detecting fordable device.
Some of my own idea is to check the screen resolution size? As that would differ somehow from other phones !

is simple:
I use this code im my apps, I share it with you
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TelephonyManager manager = (TelephonyManager)getApplicationContext().getSystemService(Context.TELEPHONY_SERVICE);
if (Objects.requireNonNull(manager).getPhoneType() == TelephonyManager.PHONE_TYPE_NONE) {
Toast.makeText(MainActivity.this, "Detected... You're using a Tablet", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "Detected... You're using a Mobile Phone", Toast.LENGTH_SHORT).show();
}
}
}

'MyApp' has stopped and forcing to close

I'm developing Android app on Android studio using Opencv library and when I try to open my app it opens then right after that it closes and displaying crash message. I'm new on mobile development
Using : OpenCV310, Android Studio 3.0,
public class ScanLicensePlateActivity extends AppCompatActivity {
protected AnylineOcrScanView scanView;
private LicensePlateResultView licensePlateResultView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Set the flag to keep the screen on (otherwise the screen may go dark during scanning)
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.activity_anyline_ocr);
String license = getString(R.string.anyline_license_key);
// Get the view from the layout
scanView = (AnylineOcrScanView) findViewById(R.id.scan_view);
// Configure the view (cutout, the camera resolution, etc.) via json
// (can also be done in xml in the layout)
scanView.setConfig(new AnylineViewConfig(this, "license_plate_view_config.json"));
// Copies given traineddata-file to a place where the core can access it.
// This MUST be called for every traineddata file that is used
// (before startScanning() is called).
// The file must be located directly in the assets directory
// (or in tessdata/ but no other folders are allowed)
scanView.copyTrainedData("tessdata/GL-Nummernschild-Mtl7_uml.traineddata",
"8ea050e8f22ba7471df7e18c310430d8");
scanView.copyTrainedData("tessdata/Arial.traineddata", "9a5555eb6ac51c83cbb76d238028c485");
scanView.copyTrainedData("tessdata/Alte.traineddata", "f52e3822cdd5423758ba19ed75b0cc32");
scanView.copyTrainedData("tessdata/deu.traineddata", "2d5190b9b62e28fa6d17b728ca195776");
// Configure the OCR for license plate scanning via a custom script file
// This is how you could add custom scripts optimized by Anyline for your use-case
AnylineOcrConfig anylineOcrConfig = new AnylineOcrConfig();
anylineOcrConfig.setCustomCmdFile("license_plates.ale");
// set the ocr config
scanView.setAnylineOcrConfig(anylineOcrConfig);
// initialize with the license and a listener
scanView.initAnyline(license, new AnylineOcrListener() {
#Override
public void onReport(String identifier, Object value) {
// Called with interesting values, that arise during processing.
// Some possibly reported values:
//
// $brightness - the brightness of the center region of the cutout as a float value
// $confidence - the confidence, an Integer value between 0 and 100
// $thresholdedImage - the current image transformed into black and white
// $sharpness - the detected sharpness value (only reported if minSharpness > 0)
}
#Override
public boolean onTextOutlineDetected(List<PointF> list) {
// Called when the outline of a possible text is detected.
// If false is returned, the outline is drawn automatically.
return false;
}
#Override
public void onResult(AnylineOcrResult result) {
// Called when a valid result is found
String results[] = result.getText().split("-");
String licensePlate = results[1];
licensePlateResultView.setLicensePlate(licensePlate);
licensePlateResultView.setVisibility(View.VISIBLE);
}
#Override
public void onAbortRun(AnylineOcrError code, String message) {
// Is called when no result was found for the current image.
// E.g. if no text was found or the result is not valid.
}
});
// disable the reporting if set to off in preferences
if (!PreferenceManager.getDefaultSharedPreferences(this).getBoolean(
SettingsFragment.KEY_PREF_REPORTING_ON, true)) {
// The reporting of results - including the photo of a scanned meter -
// helps us in improving our product, and the customer experience.
// However, if you wish to turn off this reporting feature, you can do it like this:
scanView.setReportingEnabled(false);
}
addLicensePlateResultView();
}
private void addLicensePlateResultView() {
RelativeLayout mainLayout = (RelativeLayout) findViewById(R.id.main_layout);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);
params.addRule(RelativeLayout.CENTER_VERTICAL, RelativeLayout.TRUE);
licensePlateResultView = new LicensePlateResultView(this);
licensePlateResultView.setVisibility(View.INVISIBLE);
mainLayout.addView(licensePlateResultView, params);
licensePlateResultView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startScanning();
}
});
}
private void startScanning() {
licensePlateResultView.setVisibility(View.INVISIBLE);
// this must be called in onResume, or after a result to start the scanning again
scanView.startScanning();
}
#Override
protected void onResume() {
super.onResume();
startScanning();
}
#Override
protected void onPause() {
super.onPause();
scanView.cancelScanning();
scanView.releaseCameraInBackground();
}
#Override
public void onBackPressed() {
if (licensePlateResultView.getVisibility() == View.VISIBLE) {
startScanning();
} else {
super.onBackPressed();
}
}
#Override
protected void onDestroy() {
super.onDestroy();
}}
source code is here.
If possible please help.
Logcat error shown here

Ideally more information regarding the error would be best i.e the opencv library version etc. Given it seems to be an Android issue, I would advise
File and issue or view issues pertaining to this error on their github page. Search for related Android errors to see if they match.
IF you cannot find a related error, file an issue there.

Issue with endless loop in android studio

Working in Android Studio and I've run into a few small issues so I figured I would ask for help / advice.
I am currently working on a small testing application that would allow users to open the application and select practice test or timed test (as displayed in picture 1). If users select practice test they have unlimited time to select an answer and the systems tells them if they have picked the correct answer. If the user selects timed than the system allots a predetermined amount of time and after each question the score is added and calculated, here lies my issues.
1.) Right now my code loops endlessly, ideally (at least for the timed aspect) I want my code to go through the 5 questions scoring the correct or incorrect based on the users selection. Then I want to display the # correct and in correct.
So my question is two fold, first how do I go about preventing my code from looping endless so I can begin to record iterations as ++correctAnswer ++incorrect answer. And, when it comes time to display the results, should I create a new activity to display the results.
Android is a bit confusing to me, I hope I have provided enough information and I appreciate and helping advice.
Thank You
** Code **
private int currentQuestion;
private String[] questions;
private String[] answers;
private Button answerButton;
private Button questionButton;
private TextView questionView;
private TextView answerView;
private EditText answerText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
public void init()
{
questions = new String[]{"What is the acronym for Computer Science and Information Management?",
"What is the CSIT corse number of the class you are currently in?",
"What Android program do we use to create android applications?"};
answers = new String[]{"CSIT","2250", "Android Studio"};
currentQuestion = -1;
answerButton = (Button)findViewById(R.id.AnswerButton);
questionButton = (Button)findViewById(R.id.QuestionButton);
questionView = (TextView)
findViewById(R.id.QuestionTextView);
answerView = (TextView) findViewById(R.id.AnswerTextView);
answerText = (EditText) findViewById(R.id.AnswerText);
answerButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
checkAnswer();
}});
questionButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
showQuestion();
}});
}
// Display current quesiton
public void showQuestion()
{
currentQuestion++;
if(currentQuestion == questions.length)
currentQuestion =0;
questionView.setText(questions[currentQuestion]);
answerView.setText("");
answerText.setText("");
}
// Return true if answer is correct
public boolean isCorrect(String answer)
{
return (answer.equalsIgnoreCase(answers[currentQuestion]));
}
// Display correct or incorrec results
public void checkAnswer()
{
String answer = answerText.getText().toString();
if(isCorrect(answer))
answerView.setText("You are correct!");
else
answerView.setText("Sorry, the correct answer is "+answers[currentQuestion]);
}}
Home Screen
Quiz Screen

Just have a condition check if currentQuestion == 5 at the end of checkAnswer(). If so proceed to the results screen

Android AdMob addTestDevice not getting deviceID in logcat

I am attempting to implement the AdMob with Google Play Services.
So far I have the default test banner appearing but I want to try some of the test ads.
I read that the emulator (AVD) must have Google APIs 16 or 17 as the target in order to test the AdMob however when I create a device that has this as target the emulator fails to load ( i left it for a good 20 minutes still has not loaded yet :( I just see the flashing android logo
This my AVD device
This is my AdFragment class that contains all the code related to the advertisements
public class AdFragment extends Fragment
{
private AdView mAdView;
#Override
public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState) {
// TODO Auto-generated method stub
return inflater.inflate(R.layout.fragment_ad, container, false);
}
#Override
public void onActivityCreated(Bundle savedInstanceState)
{
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
mAdView = (AdView)getView().findViewById(R.id.adView);
AdRequest adRequest = new AdRequest.Builder()
.addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
.build();
// Start loading the ad in the background.
mAdView.loadAd(adRequest);
}
/** Called when leaving the activity */
#Override
public void onPause()
{
if (mAdView != null)
{
mAdView.pause();
}
super.onPause();
}
/** Called when returning to the activity */
#Override
public void onResume()
{
super.onResume();
if (mAdView != null)
{
mAdView.resume();
}
}
/** Called before the activity is destroyed */
#Override
public void onDestroy() {
if (mAdView != null)
{
mAdView.destroy();
}
super.onDestroy();
}
}
Now im unsure whether it is my code that not generating the device ID or a problem with my created AVD device. The tutorials i seen have something like this
.addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
.addTestDevice("2EAB96D84FE62876379A9C030AA6A0AC")
Now i don't know if the last line is the code given by LogCat or is something that i just have to put in. I noticed the developer.google website has a different code so i assume i don't need to include in my code since i have not got it yet.
Please help. thank you.
UPDATE 1
I added this code inside On Resume inside my main activity
#Override
protected void onResume()
{
// TODO Auto-generated method stub
super.onResume();
int isAvaiable = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if(isAvaiable == ConnectionResult.SUCCESS)
{
Log.d("TEST", "GPS IS OK");
}
else if(isAvaiable == ConnectionResult.SERVICE_MISSING || isAvaiable == ConnectionResult.SERVICE_VERSION_UPDATE_REQUIRED || isAvaiable == ConnectionResult.SERVICE_DISABLED)
{
Dialog dialog = GooglePlayServicesUtil.getErrorDialog(isAvaiable, this, 1);
dialog.show();
}
}

The API to test banners should be 17 or higher. You have a good answer here that explains it. GPS in emulator.
For the problems related to launch the emulator the only suggestion I can give you is trying VM Acceleration and use an smaller screen.
You can try other emulators like x86Emulator and download and the last ISO versions 4.4. In my case the default android emulator took 10-12minutes to be responsive in a ldpi, with the other only 2 in a hdpi.
About the addTestDevice, I think AdRequest.DEVICE_ID_EMULATOR is enough, but if you see in the logcat the MD5 of your device ID then add this hash.
Last but not least, remember to check if GPS are installed at the beginning, it is explained on the DOCS.
To verify the Google Play services version, call isGooglePlayServicesAvailable(). If the result code is SUCCESS, then the Google Play services APK is up-to-date and you can continue to make a connection. If, however, the result code is SERVICE_MISSING, SERVICE_VERSION_UPDATE_REQUIRED, or SERVICE_DISABLED, then the user needs to install an update.
So you will avoid errors.

Android - security through inheritence

I want to extend a common security check to nearly every view of my application. To do this, I have made this class
public class ProtectedActivity extends ActivityBase {
boolean isAuthenticated = false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Thread validationThread = new Thread()
{
#Override
public void run()
{
try
{
isAuthenticated = UserService.validateToken();
}
catch (FTNIServiceException e)
{
//eat it
}
finally
{
if (!isAuthenticated)
{
startActivity(new Intent(ProtectedActivity.this, SignInActivity.class));
finish();
}
}
}
};
validationThread.start();
}
}
The logic is simple. Validate the user against my restful api to make sure they are signed in. If they aren't, show them to the signin page.
This works great, because to add the security check, all I need to do is inherit from my ProtectedActivity.
public class MainMenuActivity extends ProtectedActivity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
}
The problem is, however, that I periodically receive View not attached to window manager errors. I understand why this is happening. I am starting a new intent in the parent class, and the child lives on. to attempt to alter it's view even though a new intent has started. What is a better way to handle this so that if a user is not authenticated (such as their session expires serverside), it won't error when sending the user to the sign in screen?

Don't you Thread. Use AsyncTask instead which should handle your references to windows correctly.
On a different note, I would change this to a different implementation. Why don't use the Preferences storage on the phone to store some kind token. If the token is not valid then request a new token and all the stuff you are doing currently. This way is better because you don't want to request a REST call every time.
I imagine something like this (pseudo code)
Check if credentials exist in Preference
if(valid) then do nothing
else use AsyncTask and pop up a loader screen "Waiting..."