react-native/Examples/UIExplorer/AppStateExample.js

82 lines
2.3 KiB
JavaScript

/**
* The examples provided by Facebook are for non-commercial testing and
* evaluation purposes only.
*
* Facebook reserves all rights not expressly granted.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON INFRINGEMENT. IN NO EVENT SHALL
* FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* @providesModule AppStateExample
* @flow
*/
'use strict';
var React = require('react');
var ReactNative = require('react-native');
var {
AppState,
Text,
View
} = ReactNative;
var AppStateSubscription = React.createClass({
getInitialState() {
return {
appState: AppState.currentState,
previousAppStates: [],
};
},
componentDidMount: function() {
AppState.addEventListener('change', this._handleAppStateChange);
},
componentWillUnmount: function() {
AppState.removeEventListener('change', this._handleAppStateChange);
},
_handleAppStateChange: function(appState) {
var previousAppStates = this.state.previousAppStates.slice();
previousAppStates.push(this.state.appState);
this.setState({
appState,
previousAppStates,
});
},
render() {
if (this.props.showCurrentOnly) {
return (
<View>
<Text>{this.state.appState}</Text>
</View>
);
}
return (
<View>
<Text>{JSON.stringify(this.state.previousAppStates)}</Text>
</View>
);
}
});
exports.title = 'AppState';
exports.description = 'app background status';
exports.examples = [
{
title: 'AppState.currentState',
description: 'Can be null on app initialization',
render() { return <Text>{AppState.currentState}</Text>; }
},
{
title: 'Subscribed AppState:',
description: 'This changes according to the current state, so you can only ever see it rendered as "active"',
render(): ReactElement { return <AppStateSubscription showCurrentOnly={true} />; }
},
{
title: 'Previous states:',
render(): ReactElement { return <AppStateSubscription showCurrentOnly={false} />; }
},
];