154 lines
4.1 KiB
JavaScript
154 lines
4.1 KiB
JavaScript
/**
|
|
* Copyright (c) 2015-present, Facebook, Inc.
|
|
*
|
|
* This source code is licensed under the MIT license found in the
|
|
* LICENSE file in the root directory of this source tree.
|
|
*
|
|
* @format
|
|
* @flow
|
|
*/
|
|
|
|
'use strict';
|
|
|
|
var React = require('react');
|
|
var ReactNative = require('react-native');
|
|
var {Image, LayoutAnimation, StyleSheet, Text, View} = ReactNative;
|
|
|
|
import type {ViewLayout, ViewLayoutEvent} from 'ViewPropTypes';
|
|
|
|
type State = {
|
|
containerStyle?: {|width: number|},
|
|
extraText?: string,
|
|
imageLayout?: ViewLayout,
|
|
textLayout?: ViewLayout,
|
|
viewLayout?: ViewLayout,
|
|
viewStyle: {|margin: number|},
|
|
};
|
|
|
|
class LayoutEventExample extends React.Component<{}, State> {
|
|
state: State = {
|
|
viewStyle: {
|
|
margin: 20,
|
|
},
|
|
};
|
|
|
|
animateViewLayout = () => {
|
|
LayoutAnimation.configureNext(LayoutAnimation.Presets.spring, () => {
|
|
console.log('layout animation done.');
|
|
this.addWrapText();
|
|
});
|
|
this.setState({
|
|
viewStyle: {
|
|
margin: this.state.viewStyle.margin > 20 ? 20 : 60,
|
|
},
|
|
});
|
|
};
|
|
|
|
addWrapText = () => {
|
|
this.setState(
|
|
{extraText: ' And a bunch more text to wrap around a few lines.'},
|
|
this.changeContainer,
|
|
);
|
|
};
|
|
|
|
changeContainer = () => {
|
|
this.setState({containerStyle: {width: 280}});
|
|
};
|
|
|
|
onViewLayout = (e: ViewLayoutEvent) => {
|
|
console.log('received view layout event\n', e.nativeEvent);
|
|
this.setState({viewLayout: e.nativeEvent.layout});
|
|
};
|
|
|
|
onTextLayout = (e: ViewLayoutEvent) => {
|
|
console.log('received text layout event\n', e.nativeEvent);
|
|
this.setState({textLayout: e.nativeEvent.layout});
|
|
};
|
|
|
|
onImageLayout = (e: ViewLayoutEvent) => {
|
|
console.log('received image layout event\n', e.nativeEvent);
|
|
this.setState({imageLayout: e.nativeEvent.layout});
|
|
};
|
|
|
|
render() {
|
|
var viewStyle = [styles.view, this.state.viewStyle];
|
|
var textLayout = this.state.textLayout || {width: '?', height: '?'};
|
|
var imageLayout = this.state.imageLayout || {x: '?', y: '?'};
|
|
return (
|
|
<View style={this.state.containerStyle}>
|
|
<Text>
|
|
layout events are called on mount and whenever layout is recalculated.
|
|
Note that the layout event will typically be received{' '}
|
|
<Text style={styles.italicText}>before</Text> the layout has updated
|
|
on screen, especially when using layout animations.{' '}
|
|
<Text style={styles.pressText} onPress={this.animateViewLayout}>
|
|
Press here to change layout.
|
|
</Text>
|
|
</Text>
|
|
<View ref="view" onLayout={this.onViewLayout} style={viewStyle}>
|
|
<Image
|
|
ref="img"
|
|
onLayout={this.onImageLayout}
|
|
style={styles.image}
|
|
source={{
|
|
uri:
|
|
'https://fbcdn-dragon-a.akamaihd.net/hphotos-ak-prn1/t39.1997/p128x128/851561_767334496626293_1958532586_n.png',
|
|
}}
|
|
/>
|
|
<Text>
|
|
ViewLayout:{' '}
|
|
{JSON.stringify(this.state.viewLayout, null, ' ') + '\n\n'}
|
|
</Text>
|
|
<Text ref="txt" onLayout={this.onTextLayout} style={styles.text}>
|
|
A simple piece of text.{this.state.extraText}
|
|
</Text>
|
|
<Text>
|
|
{'\n'}
|
|
Text w/h: {textLayout.width}/{textLayout.height + '\n'}
|
|
Image x/y: {imageLayout.x}/{imageLayout.y}
|
|
</Text>
|
|
</View>
|
|
</View>
|
|
);
|
|
}
|
|
}
|
|
|
|
var styles = StyleSheet.create({
|
|
view: {
|
|
padding: 12,
|
|
borderColor: 'black',
|
|
borderWidth: 0.5,
|
|
backgroundColor: 'transparent',
|
|
},
|
|
text: {
|
|
alignSelf: 'flex-start',
|
|
borderColor: 'rgba(0, 0, 255, 0.2)',
|
|
borderWidth: 0.5,
|
|
},
|
|
image: {
|
|
width: 50,
|
|
height: 50,
|
|
marginBottom: 10,
|
|
alignSelf: 'center',
|
|
},
|
|
pressText: {
|
|
fontWeight: 'bold',
|
|
},
|
|
italicText: {
|
|
fontStyle: 'italic',
|
|
},
|
|
});
|
|
|
|
exports.title = 'Layout Events';
|
|
exports.description =
|
|
'Examples that show how Layout events can be used to ' +
|
|
'measure view size and position.';
|
|
exports.examples = [
|
|
{
|
|
title: 'LayoutEventExample',
|
|
render: function(): React.Element<any> {
|
|
return <LayoutEventExample />;
|
|
},
|
|
},
|
|
];
|