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

        mContentView = findViewById(R.id.content);
        mLoadingView = findViewById(R.id.loading_spinner);

        // Initially hide the content view.
        mContentView.setVisibility(View.GONE);

        // Retrieve and cache the system's default "short" animation time.
        mShortAnimationDuration = getResources().getInteger(android.R.integer.config_shortAnimTime);
    }
The system "short" animation time duration, in milliseconds. This duration is ideal for
subtle animations or animations that occur very frequently.
app/src/main/java/home/smart/fly/animations/ui/activity/demos/CrossfadeActivity.java