Permission error is still showing even when added

问题:

I implemented AlertDialog in my class which extend Application class, also added proper permission in manifest file:

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

See my code:

private void showAlertDialog(Context context) {
    DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            // do some stuff eg: context.onCreate(super)
        }
    };

    AlertDialog.Builder builder = new AlertDialog.Builder(context)
        .setCancelable(false)
        .setMessage("Messag...")
        .setTitle("Title")
        .setPositiveButton("OK", listener);

        Dialog dialog = builder.create();
        dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
        dialog.show();
}

Call Method:

showAlertDialog(getApplicationContext());

I tried this answer, it was working yesterday, now is not working: How to show Dialog Box from the class which extends Application in android?

BTW, it was working yesterday, I don't know why it is not working today, what am I missing?

回答1:

Did you define runtime permissions if you are checking in marshmallow or above API level devices?

Check the overlay permission

public static int OVERLAY_PERMISSION_REQ_CODE = 1234;

public void someMethod() {
if (!Settings.canDrawOverlays(this)) {
    Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
            Uri.parse("package:" + getPackageName()));
    startActivityForResult(intent, OVERLAY_PERMISSION_REQ_CODE);
}}

In onActivityResult,

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == OVERLAY_PERMISSION_REQ_CODE) {
        if (!Settings.canDrawOverlays(this)) {
            // SYSTEM_ALERT_WINDOW permission not granted...
        }
    }
}

Finally----

Check if the device has API 23+

if 23+ API then check if the user has permission or not

if had permit once don't drive him to Settings.ACTION_MANAGE_OVERLAY_PERMISSION and if has not to permit yet then ask for runtime permission check

Put below the line in your onCreate() method. Put this after setContentView()

checkPermission();

Now put below code in onActivityResult,

@TargetApi(Build.VERSION_CODES.M)
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == ACTION_MANAGE_OVERLAY_PERMISSION_REQUEST_CODE) {
        if (!Settings.canDrawOverlays(this)) {
            // You don't have permission
            checkPermission();
        } else {
            // Do as per your logic 
        }
    }
}

Now finally the checkPermission method code,

public void checkPermission() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    if (!Settings.canDrawOverlays(this)) {
        Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
                Uri.parse("package:" + getPackageName()));
        startActivityForResult(intent, ACTION_MANAGE_OVERLAY_PERMISSION_REQUEST_CODE);
    }
}}

And declare a variable as global

public static int ACTION_MANAGE_OVERLAY_PERMISSION_REQUEST_CODE = 5469;

Happy Coding :)