Dialog

public class PreferenceUtils {

    private PreferenceUtils(){}

    public static int setResources (String string, String string2, Context context){
        return context.getResources().getIdentifier(string, string2, context.getPackageName());
    }

    public static void dialogOption(final Activity activity){
        Context context = activity;
        if (!Boolean.valueOf((boolean) PreferenceManager.getDefaultSharedPreferences(context).getBoolean("disable_dialog_key", false)).booleanValue()) {
            return;
        }else{
            tampilkanDialog(activity);
        }
    }

    public static void tampilkanDialog(final Activity activity){

        final AlertDialog.Builder adb = new AlertDialog.Builder(activity);
        LayoutInflater adbInflater = LayoutInflater.from(activity);
        View view = adbInflater.inflate(setResources("dialog_about", "layout", activity), null);
        adb.setView(view);
        adb.setNeutralButton("Dismiss", new DialogInterface.OnClickListener() {
            @RequiresApi(api = Build.VERSION_CODES.HONEYCOMB)
            public void onClick(DialogInterface dialog, int which) {
                return;
            }
        });
        adb.show();

    }
}

==== Letakan di activity dimana mau ditampilkan dialog
PreferenceUtils.dialogOption(this);

contoh :
public class MainActivity extends AppCompatActivity {

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

}