As explained in the ArActivity section, augmented reality view takes some time to initialize.
You can be notified of the augmented reality view initialization complete by calling ArActivity.addArViewInitListener(InitStatusListener listener). The onInitComplete() callback will be called when initialization finished.
Note: all InitStatusListener listeners are automatically removed either when onInitComplete() is called or when augmented reality view is destroyed.
You can also check if augmented reality view is initialized at any time by calling ArActivity.isArViewInitialized().