On Incoming Call when app is in background or app is not running the broadcast receiver is not called

Question

I am developing a custom incoming call screen but my problem is that when the app is in foreground, on incoming call the broadcast receiver is called and displays the custom screen but when the app is in the background or not in running state then the broadcast receiver is not called.
How to resolve this?

<uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.CALL_PHONE" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".AcceptCall"
            android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.ANSWER" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>

        <receiver
            android:name=".broadcast.PhoneListenerBroad">
            <intent-filter>
                <action android:name="android.intent.action.PHONE_STATE" />
            </intent-filter>
        </receiver>
    </application>

public class PhoneListenerBroad extends BroadcastReceiver {

    Context c;
    private String outgoing;

    @Override
    public void onReceive(Context context, Intent intent) {
        c = context;

        Log.d("arsalan","Broadcast receiver is called");

        try {
            TelephonyManager tmgr = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
            MyPhoneStateListener PhoneListener = new MyPhoneStateListener();
            tmgr.listen(PhoneListener, PhoneStateListener.LISTEN_CALL_STATE);
        } catch (Exception e) {
            Log.e("Phone Receive Error", " " + e);
        }

    }

    private class MyPhoneStateListener extends PhoneStateListener {
        public void onCallStateChanged(final int state, final String incomingNumber) {

            if (state == TelephonyManager.CALL_STATE_RINGING) {
                Intent intentPhoneCall = new Intent(c, AcceptCall.class);
                intentPhoneCall.putExtra("incomingnumber", incomingNumber);
                intentPhoneCall.putExtra("state", state);
                intentPhoneCall.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                intentPhoneCall.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                c.startActivity(intentPhoneCall);
                Log.d("arsalan","incoming call: "+incomingNumber);
            }
        }
    }
}

Currently there is nothing special in this class 目前在此类中没有什么特别的

public class AcceptCall extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_accept_call);

        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

    }
}

Answer 1

/**
 * Method checks if the app is in background or not
 *
 * @param context Application context
 * @return True/False
 */
public static boolean isAppIsInBackground(Context context) {
    boolean isInBackground = true;
    ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT_WATCH) {
        List<ActivityManager.RunningAppProcessInfo> runningProcesses = am.getRunningAppProcesses();
        for (ActivityManager.RunningAppProcessInfo processInfo : runningProcesses) {
            if (processInfo.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                for (String activeProcess : processInfo.pkgList) {
                    if (activeProcess.equals(context.getPackageName())) {
                        isInBackground = false;
                    }
                }
            }
        }
    } else {
        List<ActivityManager.RunningTaskInfo> taskInfo = am.getRunningTasks(1);
        ComponentName componentInfo = taskInfo.get(0).topActivity;
        if (componentInfo.getPackageName().equals(context.getPackageName())) {
            isInBackground = false;
        }
    }

    return isInBackground;
}