怎么在React中利用Native实现一个进度条弹框?很多新手对此不是很清楚,为了帮助大家解决这个难题,下面小编将为大家详细讲解,有这方面需求的人可以来学习下,希望你能有所收获。

首先实现进度条。
import React, {
PureComponent
} from 'react';
import {
StyleSheet,
View,
Animated,
Easing,
} from 'react-native';
class Bar extends PureComponent {
constructor(props) {
super(props);
this.progress = new Animated.Value(this.props.initialProgress || 0);
}
static defaultProps = {
style: styles,
easing: Easing.inOut(Easing.ease)
}
componentWillReceiveProps(nextProps) {
if (this.props.progress >= 0 && this.props.progress !== nextProps.progress) {
this.update(nextProps.progress);
}
}
shouldComponentUpdate() {
return false;
}
update(progress) {
Animated.spring(this.progress, {
toValue: progress
}).start();
}
render() {
return (
);
}
}
var styles = StyleSheet.create({
background: {
backgroundColor: '#bbbbbb',
height: 5,
overflow: 'hidden'
},
fill: {
backgroundColor: 'rgba(0, 122, 255, 1)',
height: 5
}
});
export default Bar;进度条的值我们用动画实现,避免使用state不断去重新render渲染界面,同时设置shouldComponentUpdate返回值为false,避免重新render。
实现进度条弹框。
import React, {
PropTypes,
PureComponent
} from 'react';
import {
View,
StyleSheet,
Modal,
Text,
Dimensions,
TouchableOpacity
} from 'react-native';
import Bar from './Bar';
const {
width
} = Dimensions.get('window');
class ProgressBarDialog extends PureComponent {
constructor(props) {
super(props);
}
static propTypes = {
...Modal.propTypes,
title: PropTypes.string,
canclePress: PropTypes.func,
cancleText: PropTypes.string,
needCancle: PropTypes.bool
};
static defaultProps = {
animationType: 'none',
transparent: true,
progressModalVisible: false,
onShow: () => {},
onRequestClose: () => {},
onOutSidePress: () => {},
title: '上传文件',
cancleText: '取消是',
canclePress: () => {},
needCancle: true
}
render() {
const {
animationType,
transparent,
onRequestClose,
progress,
title,
canclePress,
cancleText,
needCancle,
progressModalVisible
} = this.props;
return (
{title}
{`${progress}`}%
{`${progress}`}/100
{needCancle &&
{cancleText}
}
);
}
}
const styles = StyleSheet.create({
progressBarView: {
flex:1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: 'rgba(0,0,0,0.2)'
},
barStyle: {
marginLeft: 10,
marginRight: 10,
width:width - 80
},
progressLeftText: {
fontSize: 14
},
cancleContainer: {
justifyContent: 'center',
alignItems: 'flex-end'
},
progressRightText: {
fontSize: 14,
color: '#666666'
},
barBackgroundStyle: {
backgroundColor: '#cccccc'
},
progressContainer: {
flexDirection: 'row',
padding: 10,
justifyContent: 'space-between'
},
subView: {
marginLeft: 30,
marginRight: 30,
backgroundColor: '#fff',
alignSelf: 'stretch',
justifyContent: 'center'
},
progressView: {
flexDirection: 'row',
padding: 10,
paddingBottom: 5,
justifyContent: 'space-between'
},
title: {
textAlign: 'left',
padding:10,
fontSize: 16
},
cancleButton: {
padding:10
},
cancleText: {
textAlign: 'right',
paddingTop: 0,
fontSize: 16,
color: 'rgba(0, 122, 255, 1)'
}
});
export default ProgressBarDialog;props
modal的props - 这些都是modal的属性
animationType - 动画类型
transparent - 是否透明
progressModalVisible - 是否可见
onShow - 弹框出现
onRequestClose - 弹框请求消失(比如安卓按返回键会触发这个方法)
onOutSidePress - 点击弹框外部动作
title - 弹框的标题
cancleText - 取消的文字
canclePress - 取消动作
needCancle - 是否需要取消按钮
使用代码
import React , {
PureComponent
} from 'react';
import {
View
} from 'react-native';
import ProgressBarDialog from './ProgressBarDialog';
class Upload extends PureComponent {
constructor(props) {
this.state = {
progress: 0,
progressModalVisible: false
};
}
refProgressBar = (view) => {
this.progressBar = view;
}
showProgressBar = () => {
this.setState({
progressModalVisible: true
});
}
dismissProgressBar = () => {
this.setState({
progress: 0,
progressModalVisible: false
});
}
setProgressValue = (progress) => {
this.setState({
progress
});
}
onProgressRequestClose = () => {
this.dismissProgressBar();
}
canclePress = () => {
this.dismissProgressBar();
}
render() {
return (
)
}
}
export default Upload;看完上述内容是否对您有帮助呢?如果还想对相关知识有进一步的了解或阅读更多相关文章,请关注创新互联网站建设公司行业资讯频道,感谢您对创新互联建站的支持。
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