Android app terminates after certain time when minimized

Question

I have this app which parses SMS and then converts them into Audio. My app users usually minimize the app and runs it all the time. But my app is getting terminated after sometime. How can i make sure my app will run till a user "terminates" it. Since the core functionality of the app is to convert SMS to audio, i need it running all the time.How can i do this ?

My current MainActivity.java

public class MainActivity extends AppCompatActivity {

    TextView txtGateway, txtTime, txtAmount;
    Speakerbox speakerbox;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //textView = findViewById(R.id.txt_message);
        speakerbox = new Speakerbox(getApplication());
        txtAmount = findViewById(R.id.tv_amount);
        txtGateway = findViewById(R.id.tv_gateway);
        txtTime = findViewById(R.id.tv_time);
        requestSmsPermission();

    }


    @Override
    public void onResume() {
        LocalBroadcastManager.getInstance(this).registerReceiver(receiver, new IntentFilter("otp"));
        super.onResume();
    }
    @Override
    public void onPause() {
        LocalBroadcastManager.getInstance(this).registerReceiver(receiver, new IntentFilter("otp"));
        super.onPause();
    }
    private BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equalsIgnoreCase("otp")) {
                final String message = intent.getStringExtra("message");
                String gateway = intent.getStringExtra("gateway");
                String time = intent.getStringExtra("time");
                String amount = intent.getStringExtra("amount");
                speakerbox.play(message);
                txtGateway.setText(gateway);
                txtTime.setText(time);
                txtAmount.setText(amount);


                // message is the fetching OTP
            }
        }
    };




    /**
     * Requesting multiple permissions (storage and location) at once
     * This uses multiple permission model from dexter
     * On permanent denial opens settings dialog
     */
    private void requestSmsPermission() {
        Dexter.withActivity(this)
                .withPermissions(
                        Manifest.permission.RECEIVE_SMS,
                        Manifest.permission.READ_SMS,
                        Manifest.permission.SEND_SMS,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE)
                .withListener(new MultiplePermissionsListener() {
                    @Override
                    public void onPermissionsChecked(MultiplePermissionsReport report) {
                        // check if all permissions are granted
                        if (report.areAllPermissionsGranted()) {
                            //  Toast.makeText(getApplicationContext(), "All permissions are granted!", Toast.LENGTH_SHORT).show();
                        }

                        // check for permanent denial of any permission
                        if (report.isAnyPermissionPermanentlyDenied()) {
                            // show alert dialog navigating to Settings
                            showSettingsDialog();
                        }
                    }

                    @Override
                    public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {
                        token.continuePermissionRequest();
                    }
                }).
                withErrorListener(new PermissionRequestErrorListener() {
                    @Override
                    public void onError(DexterError error) {
                        Toast.makeText(getApplicationContext(), "Error occurred! ", Toast.LENGTH_SHORT).show();
                    }
                })
                .onSameThread()
                .check();
    }

    /**
     * Showing Alert Dialog with Settings option
     * Navigates user to app settings
     * NOTE: Keep proper title and message depending on your app
     */
    private void showSettingsDialog() {
        AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
        builder.setTitle("Need Permissions");
        builder.setMessage("This app needs permission to use this feature. You can grant them in app settings.");
        builder.setPositiveButton("GOTO SETTINGS", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
                openSettings();
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        });
        builder.show();

    }

    // navigating user to app settings
    private void openSettings() {
        Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
        Uri uri = Uri.fromParts("package", getPackageName(), null);
        intent.setData(uri);
        startActivityForResult(intent, 101);
    }
}

Answer 1

Use a foreground service to ensure that your app is not killed by Android. On newer version of Android, app's background process gets killed after sometime. Having a foreground service will ensure that your app stays active. Keep the service on background thread and not on the main thread.

Read more at: https://developer.android.com/guide/components/services and https://androidwave.com/foreground-service-android-example/

Answer 2

Activities are used for user facing parts of your application. Use service instead. Most likely, your application is getting terminated by os due to low memory situation.

Answer 3

如果您想一直在后台运行，请为核心功能使用服务。如果用户没有主动使用您的应用程序但应用程序正在占用 RAM 内存，那么操作系统将终止应用程序以避免内存不足。