react-native/Examples/UIExplorer/XHRExample.js

132 lines
3.2 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.
*
* @flow
*/
'use strict';
var React = require('react-native');
var {
ProgressViewIOS,
StyleSheet,
View,
Text,
TouchableHighlight,
} = React;
class Downloader extends React.Component {
xhr: XMLHttpRequest;
cancelled: boolean;
constructor(props) {
super(props);
this.cancelled = false;
this.state = {
downloading: false,
contentSize: 1,
downloaded: 0,
};
}
download() {
this.xhr && this.xhr.abort();
var xhr = this.xhr || new XMLHttpRequest();
xhr.onreadystatechange = () => {
if (xhr.readyState === xhr.HEADERS_RECEIVED) {
var contentSize = parseInt(xhr.getResponseHeader('Content-Length'), 10);
this.setState({
contentSize: contentSize,
downloaded: 0,
});
} else if (xhr.readyState === xhr.LOADING) {
this.setState({
downloaded: xhr.responseText.length,
});
} else if (xhr.readyState === xhr.DONE) {
this.setState({
downloading: false,
});
if (this.cancelled) {
this.cancelled = false;
return;
}
if (xhr.status === 200) {
alert('Download complete!');
} else if (xhr.status !== 0) {
alert('Error: Server returned HTTP status of ' + xhr.status + ' ' + xhr.responseText);
} else {
alert('Error: ' + xhr.responseText);
}
}
};
xhr.open('GET', 'http://www.gutenberg.org/cache/epub/100/pg100.txt');
xhr.send();
this.xhr = xhr;
this.setState({downloading: true});
}
componentWillUnmount() {
this.cancelled = true;
this.xhr && this.xhr.abort();
}
render() {
var button = this.state.downloading ? (
<View style={styles.wrapper}>
<View style={styles.button}>
<Text>Downloading...</Text>
</View>
</View>
) : (
<TouchableHighlight
style={styles.wrapper}
onPress={this.download.bind(this)}>
<View style={styles.button}>
<Text>Download 5MB Text File</Text>
</View>
</TouchableHighlight>
);
return (
<View>
{button}
<ProgressViewIOS progress={(this.state.downloaded / this.state.contentSize)}/>
</View>
);
}
}
exports.framework = 'React';
exports.title = 'XMLHttpRequest';
exports.description = 'XMLHttpRequest';
exports.examples = [{
title: 'File Download',
render() {
return <Downloader/>;
}
}];
var styles = StyleSheet.create({
wrapper: {
borderRadius: 5,
marginBottom: 5,
},
button: {
backgroundColor: '#eeeeee',
padding: 10,
},
});