/**
* 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.
*
* @flow
*/
'use strict';
var React = require('react-native');
var {
Image,
LayoutAnimation,
StyleSheet,
Text,
View,
} = React;
type LayoutEvent = {
nativeEvent: {
layout: {
x: number;
y: number;
width: number;
height: number;
};
};
};
var LayoutEventExample = React.createClass({
getInitialState: function() {
return {
viewStyle: {
margin: 20,
},
};
},
animateViewLayout: function() {
LayoutAnimation.configureNext(
LayoutAnimation.Presets.spring,
() => {
console.log('layout animation done.');
this.addWrapText();
}
);
this.setState({
viewStyle: {
margin: this.state.viewStyle.margin > 20 ? 20 : 60,
}
});
},
addWrapText: function() {
this.setState(
{extraText: ' And a bunch more text to wrap around a few lines.'},
this.changeContainer
);
},
changeContainer: function() {
this.setState({containerStyle: {width: 280}});
},
onViewLayout: function(e: LayoutEvent) {
console.log('received view layout event\n', e.nativeEvent);
this.setState({viewLayout: e.nativeEvent.layout});
},
onTextLayout: function(e: LayoutEvent) {
console.log('received text layout event\n', e.nativeEvent);
this.setState({textLayout: e.nativeEvent.layout});
},
onImageLayout: function(e: LayoutEvent) {
console.log('received image layout event\n', e.nativeEvent);
this.setState({imageLayout: e.nativeEvent.layout});
},
render: function() {
var viewStyle = [styles.view, this.state.viewStyle];
var textLayout = this.state.textLayout || {width: '?', height: '?'};
var imageLayout = this.state.imageLayout || {x: '?', y: '?'};
return (
layout events are called on mount and whenever layout is recalculated. Note that the layout event will typically be received before the layout has updated on screen, especially when using layout animations.{' '}
Press here to change layout.
ViewLayout: {JSON.stringify(this.state.viewLayout, null, ' ') + '\n\n'}
A simple piece of text.{this.state.extraText}
{'\n'}
Text w/h: {textLayout.width}/{textLayout.height + '\n'}
Image x/y: {imageLayout.x}/{imageLayout.y}
);
}
});
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(): ReactElement {
return ;
},
}];