White Screen when user denies an Android permission

Question

I have an android app where I request for permission when the user clicks on the camera icon. I also want for external storage

Following is my code

private boolean isCameraPermissionGranted() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
                return true;
            } else {
                requestPermissions(new String[]{Manifest.permission.CAMERA}, REQUEST_CAMERA_PERMISSION);
                return false;
            }
        }
        return false;
    }

    public boolean isStoragePermissionGranted() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (checkSelfPermission(android.Manifest.permission.WRITE_EXTERNAL_STORAGE)
                    == PackageManager.PERMISSION_GRANTED) {
                Log.v("","Permission is granted");
                return true;
            } else {

                Log.v("","Permission is revoked");
                requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_STORAGE_PERMISSION);
                return false;
            }
        }
        else { //permission is automatically granted on sdk<23 upon installation
            Log.v("","Permission is granted");
            return true;
        }
    }

@Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case REQUEST_CAMERA_PERMISSION:
                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    takePicture();
                }
                break;
            default:
                break;
        }
    }

The problem is when the user denies a permission the app is stuck on a white page.

How can I navigate back to a previous activity when user denies a permission.

Answer 1

just call onBackPressed() on permission denied like below

@Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case REQUEST_CAMERA_PERMISSION:
                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    takePicture();
                }else{
                    onBackPressed(); // or call previous activity using Intent
                }
                break;
            default:
                break;
        }
    }

add below

@Override
public void onBackPressed() {
    //this is only needed if you have specific things
    //that you want to do when the user presses the back button.
    /* your specific things...*/
    super.onBackPressed();   
}