Migrate additional docs to the new format

Summary:
[DOCS]
Closes https://github.com/facebook/react-native/pull/16874

Differential Revision: D6375515

Pulled By: hramos

fbshipit-source-id: 64359b45a37c7b478919121573ca04dbb1ce6609

Libraries/AppState/AppState.js

@@ -23,66 +23,8 @@ const invariant = require('fbjs/lib/invariant');
  * `AppState` can tell you if the app is in the foreground or background,
  * and notify you when the state changes.
  *
- * AppState is frequently used to determine the intent and proper behavior when
- * handling push notifications.
- *
- * ### App States
- *
- *  - `active` - The app is running in the foreground
- *  - `background` - The app is running in the background. The user is either
- *     in another app or on the home screen
- *  - `inactive` - This is a state that occurs when transitioning between
- *     foreground & background, and during periods of inactivity such as
- *     entering the Multitasking view or in the event of an incoming call
- *
- * For more information, see
- * [Apple's documentation](https://developer.apple.com/library/ios/documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/TheAppLifeCycle/TheAppLifeCycle.html)
- *
- * ### Basic Usage
- *
- * To see the current state, you can check `AppState.currentState`, which
- * will be kept up-to-date. However, `currentState` will be null at launch
- * while `AppState` retrieves it over the bridge.
- *
- * ```
- * import React, {Component} from 'react'
- * import {AppState, Text} from 'react-native'
- *
- * class AppStateExample extends Component {
- *
- *   state = {
- *     appState: AppState.currentState
- *   }
- *
- *   componentDidMount() {
- *     AppState.addEventListener('change', this._handleAppStateChange);
- *   }
- *
- *   componentWillUnmount() {
- *     AppState.removeEventListener('change', this._handleAppStateChange);
- *   }
- *
- *   _handleAppStateChange = (nextAppState) => {
- *     if (this.state.appState.match(/inactive|background/) && nextAppState === 'active') {
- *       console.log('App has come to the foreground!')
- *     }
- *     this.setState({appState: nextAppState});
- *   }
- *
- *   render() {
- *     return (
- *       <Text>Current state is: {this.state.appState}</Text>
- *     );
- *   }
- *
- * }
- * ```
- *
- * This example will only ever appear to say "Current state is: active" because
- * the app is only visible to the user when in the `active` state, and the null
- * state will happen only momentarily.
+ * See http://facebook.github.io/react-native/docs/appstate.html
  */
-
 class AppState extends NativeEventEmitter {
 
   _eventHandlers: Object;
@@ -104,10 +46,10 @@ class AppState extends NativeEventEmitter {
 
     let eventUpdated = false;
 
-    // TODO: this is a terrible solution - in order to ensure `currentState` prop
-    // is up to date, we have to register an observer that updates it whenever
-    // the state changes, even if nobody cares. We should just deprecate the
-    // `currentState` property and get rid of this.
+    // TODO: this is a terrible solution - in order to ensure `currentState`
+    // prop is up to date, we have to register an observer that updates it 
+    // whenever the state changes, even if nobody cares. We should just 
+    // deprecate the `currentState` property and get rid of this.
     this.addListener(
       'appStateDidChange',
       (appStateData) => {
@@ -117,8 +59,8 @@ class AppState extends NativeEventEmitter {
     );
 
     // TODO: see above - this request just populates the value of `currentState`
-    // when the module is first initialized. Would be better to get rid of the prop
-    // and expose `getCurrentAppState` method directly.
+    // when the module is first initialized. Would be better to get rid of the
+    // prop and expose `getCurrentAppState` method directly.
     RCTAppState.getCurrentAppState(
       (appStateData) => {
         if (!eventUpdated) {
@@ -129,15 +71,16 @@ class AppState extends NativeEventEmitter {
     );
   }
 
-  /**
+  // TODO: now that AppState is a subclass of NativeEventEmitter, we could
+  // deprecate `addEventListener` and `removeEventListener` and just use 
+  // addListener` and `listener.remove()` directly. That will be a breaking 
+  // change though, as both the method and event names are different
+  // (addListener events are currently required to be globally unique).
+   /**
    * Add a handler to AppState changes by listening to the `change` event type
-   * and providing the handler
-   *
-   * TODO: now that AppState is a subclass of NativeEventEmitter, we could deprecate
-   * `addEventListener` and `removeEventListener` and just use `addListener` and
-   * `listener.remove()` directly. That will be a breaking change though, as both
-   * the method and event names are different (addListener events are currently
-   * required to be globally unique).
+   * and providing the handler.
+   * 
+   * See http://facebook.github.io/react-native/docs/appstate.html#addeventlistener
    */
   addEventListener(
     type: string,
@@ -163,7 +106,9 @@ class AppState extends NativeEventEmitter {
   }
 
   /**
-   * Remove a handler by passing the `change` event type and the handler
+   * Remove a handler by passing the `change` event type and the handler.
+   * 
+   * See http://facebook.github.io/react-native/docs/appstate.html#removeeventlistener
    */
   removeEventListener(
     type: string,
@@ -200,9 +145,10 @@ if (__DEV__ && !RCTAppState) {
     }
   }
 
-  // This module depends on the native `RCTAppState` module. If you don't include it,
-  // `AppState.isAvailable` will return `false`, and any method calls will throw.
-  // We reassign the class variable to keep the autodoc generator happy.
+  // This module depends on the native `RCTAppState` module. If you don't
+  // include it, `AppState.isAvailable` will return `false`, and any method
+  // calls will throw. We reassign the class variable to keep the autodoc
+  // generator happy.
   AppState = new MissingNativeAppStateShim();
 } else {
   AppState = new AppState();