Not Able To Get Android Run Time Permission Result

I want to check SMS reading permission is Granted or not in API 23+. So I implemented its as follows; if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_SMS) != P

Solution 1:

try this codes and also provide permissions in android manifest

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        marshmallowPermission();                        //***** marshmaloow runtime permission*****//
    }

 public Boolean marshmallowPermission(){

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (checkPermission()) {
            Toast.makeText(this,"Permission already granted.", Toast.LENGTH_SHORT).show();
        } else {
            requestPermission();
        }
    }
    return true;
}

@TargetApi(Build.VERSION_CODES.M)
public boolean checkPermission(){
int sms = checkSelfPermission(android.Manifest.permission.READ_SMS);

    if (sms == PackageManager.PERMISSION_GRANTED ){
        return true;
    } else {
        return false;
    }
}

@TargetApi(Build.VERSION_CODES.M)
public void requestPermission(){

    if (shouldShowRequestPermissionRationale(android.Manifest.permission.READ_SMS)){

         if(shouldShowRequestPermissionRationale(android.Manifest.permission.READ_SMS)){
            Toast.makeText(this,"sms Permission must be needed which allows to access sms . Please allow sms in App Settings for additional functionality.",Toast.LENGTH_LONG).show();
        }

        Intent intent = new Intent();
        intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
        Uri uri = Uri.fromParts("package", this.getPackageName(), null);
        intent.setData(uri);
        this.startActivity(intent);

    } else {

        requestPermissions(new String[]{android.Manifest.permission.READ_SMS},100);
    }
}

@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
    switch (requestCode) {
        case 100:
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this,"Permission Granted, Now you can access app without bug.",Toast.LENGTH_LONG).show();
            } else {
                Toast.makeText(this,"Permission Denied, App maybe get crashed.", Toast.LENGTH_LONG).show();
            }
            break;
    }
}