The following props are recommended, but optional. If you do not provide any props, you are responsible for coordinating loading assets, handling errors, and updating state to unmount the AppLoading component.
startAsync (function) -- A function that returns a Promise, and the Promise should resolve when the app is done loading required data and assets.
onError (function) -- If startAsync throws an error, it is caught and passed into the function provided to onError.
onFinish (function) -- (Required if you provide startAsync). Called when startAsync resolves or rejects. This should be used to set state and unmount the AppLoading component.
autoHideSplash (boolean) -- Whether to hide the native splash screen as soon as you unmount the AppLoading component. See SplashScreen module for an example.