How to show alert dialog when app is closed

Question

I am really in trouble with that situation. When a call comes, I can hold the call and number that call me. After this incoming calls, I want to show an "alert dialog "although my application is closed.

I am using the Android emulator with API >23.

Here is my mainactivity.java

public class MainActivity extends AppCompatActivity {

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

        if (ContextCompat.checkSelfPermission(MainActivity.this,
                Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
                    Manifest.permission.READ_PHONE_STATE)) {
                ActivityCompat.requestPermissions(MainActivity.this,
                        new String[]{Manifest.permission.READ_PHONE_STATE}, 1);
            } else {
                ActivityCompat.requestPermissions(MainActivity.this,
                        new String[]{Manifest.permission.READ_PHONE_STATE}, 1);
            }
        } else {
            //do nothing
        }
        if (ContextCompat.checkSelfPermission(MainActivity.this,
                Manifest.permission.READ_CALL_LOG) != PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
                    Manifest.permission.READ_CALL_LOG)) {
                ActivityCompat.requestPermissions(MainActivity.this,
                        new String[]{Manifest.permission.READ_CALL_LOG}, 2);
            } else {
                ActivityCompat.requestPermissions(MainActivity.this,
                        new String[]{Manifest.permission.READ_CALL_LOG}, 2);
            }
        } else {
            //do nothing
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case 1: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    if (ContextCompat.checkSelfPermission(MainActivity.this,
                            Manifest.permission.READ_PHONE_STATE) == PackageManager.PERMISSION_GRANTED) {
                        Toast.makeText(this, "Permission granted1", Toast.LENGTH_SHORT).show();
                    }
                } else {
                    Toast.makeText(this, "No permission granted1", Toast.LENGTH_SHORT).show();
                }
                return;
            }
            case 2: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    if (ContextCompat.checkSelfPermission(MainActivity.this,
                            Manifest.permission.READ_CALL_LOG) == PackageManager.PERMISSION_GRANTED) {
                        Toast.makeText(this, "Permission granted2", Toast.LENGTH_SHORT).show();
                    }
                } else {
                    Toast.makeText(this, "No permission granted2", Toast.LENGTH_SHORT).show();
                }
                return;
            }
        }
    }

My androidmanifest.xml

<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
<uses-permission android:name="android.permission.READ_PHONE_NUMBERS"/>
<uses-permission android:name="android.permission.READ_CALL_LOG"/>
<application
...
    <receiver android:name="InterceptCall">
         <intent-filter>
             <action android:name="android.intent.action.PHONE_STATE"/>
        </intent-filter>
    </receiver>
...

And my InterceptCall.java

public class InterceptCall extends BroadcastReceiver {

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

        try{
            String state = intent.getStringExtra(TelephonyManager.EXTRA_STATE);
            String pNum = intent.getStringExtra(TelephonyManager.EXTRA_INCOMING_NUMBER);
            if(state.equals(TelephonyManager.EXTRA_STATE_RINGING)){
                Toast.makeText(context,"Ringing State. Number is - "+pNum,Toast.LENGTH_SHORT).show();
           }
            if(state.equals(TelephonyManager.EXTRA_STATE_OFFHOOK)){

                Toast.makeText(context,"OFFHOOK// ",Toast.LENGTH_SHORT).show();

            }
            if(state.equals(TelephonyManager.EXTRA_STATE_IDLE)){
                Toast.makeText(context,"IDLE.Call End",Toast.LENGTH_SHORT).show();
            }
        }
        catch (Exception e){
            e.printStackTrace();
        }

    }
}

I really do not know what to do... or how to do it. I just want to show an alert dialog with yes/no button when the call has ended.

Answer 1

One way to create dialog when app is not open create activity use dialog theme and call it from service