RN学习-ListView列表
以下是发现模块的代码Discover.js
/**
* @providesModule Discover
*/
import React, {Component} from 'react'
// 2.导入常用组件,注册组件,样式组件,View组件,Text组件
import
{
AppRegistry,
StyleSheet,
Text,
View,
Image
}from 'react-native'
// 网络请求
var discoverData = require('../Res/discoverData.json');
// 导入自定义分组ListView
import CommonGroupListViewHeader from 'CommonGroupListViewHeader'
import Common from 'Common'
import CommonNavigationBar from 'CommonNavigationBar'
import DiscoverScrollCell from 'DiscoverScrollCell'
import DiscoverVideoCell from 'DiscoverVideoCell'
import VideoView from 'VideoView'
// 3.自定义 程序入口组件([[UIView alloc] init])
export default class Discover extends Component {
constructor(props){
super(props);
var groups = [];
// 加载第0组
this.setupGroup0(groups);
// 加载第1组
this.setupGroup1(groups);
// 加载第2组
this.setupGroup2(groups)
this.state = {
groups:groups //创建数据源,但还没有给它传递数据,使用state保存数据源,因为数据源的数据改变的时候,需要刷新界面
}
}
setupGroup0(groups){
var section = discoverData[0];
var sectionData = section.sData; // sData rData 是json数据的数据字段
var rowDatas = section.rData;
var allRowData = [];
rowDatas.forEach((rowData,i)=>{
var item = new CommonGroupListViewHeader.CommonArrowRowItem('',rowData.name,rowData.disc);
allRowData.push(item);
});
var group0 = new CommonGroupListViewHeader.CommonGroupItem(allRowData,sectionData.height);
groups.push(group0);
}
setupGroup1(groups){
var section = discoverData[1];
var sectionData = section.sData;
var rowDatas = section.rData;
var item0 = new CommonGroupListViewHeader.CommonArrowRowItem('',sectionData.name,sectionData.disc);
var item1 = new CommonGroupListViewHeader.CommonRowItem();
item1.customData = rowDatas[0];
item1.customCellType = DiscoverScrollCell;
var group1 = new CommonGroupListViewHeader.CommonGroupItem([item0,item1],sectionData.height);
groups.push(group1);
}
setupGroup2(groups){
var section = discoverData[2];
var sectionData = section.sData;
var rowDatas = section.rData;
var allRowData = [];
var item0 = new CommonGroupListViewHeader.CommonArrowRowItem('',sectionData.name);
allRowData.push(item0); // 给allRowData数据源加入头部数据
rowDatas.forEach((rowData,i)=>{ // 遍历rowDatas组数据得出行数据,加入总数据rowDatas中
var item = new CommonGroupListViewHeader.CommonRowItem();
item.customData = rowData;
item.customCellType = DiscoverVideoCell;
item.route = {
component:VideoView,
videoUri:rowData.video
}
allRowData.push(item); //给allRowData数据源加入每个cell数据
});
var group1 = new CommonGroupListViewHeader.CommonGroupItem(allRowData,sectionData.height);
groups.push(group1);
}
render(){
return (
<View>
<CommonNavigationBar
titleView={this.renderTitleView()}
/>
<CommonGroupListViewHeader.CommonGroupListView groups={this.state.groups}
groupListViewStyle={{backgroundColor:Common.bgColor}}
navigator={this.props.navigator}
titleStyle={{fontSize:18}}
subTitleStyle={{color:'rgb(80,80,80)'}}
/>
</View>
)
}
renderTitleView(){
return (
<Image source={{uri:'discover'}} style={{width:54,height:37}}/>
)
}
}
// 4.样式表 组件外观 尺寸,颜色
var styles = StyleSheet.create({
viewStyle:{
flex:1,
justifyContent:'center',
alignItems:'center'
}
})
模块当做一个对象导出知识点
/**
* @providesModule CommonGroupListViewHeader
*/
import CommonGroupItem from 'CommonGroupItem'
import CommonRowItem from 'CommonRowItem'
import CommonSwitchRowItem from 'CommonSwitchRowItem'
import CommonArrowRowItem from 'CommonArrowRowItem'
import CommonGroupListView from 'CommonGroupListView'
// 把当前模块当做一个对象导出
module.exports = {
CommonGroupItem,
CommonRowItem,
CommonSwitchRowItem,
CommonArrowRowItem,
CommonGroupListView
}
1.module.exports把里面所有内容当做一个整体,含有组头、该组所有cell类型,即CommonGroupListViewHeader拥有module.exports里面的五项内容。
比如调用CommonGroupItem的方法(给该组所有视图包括头部,尾部,cell赋值):
var group1 = new CommonGroupListViewHeader.CommonGroupItem(allRowData,sectionData.height);
2.module.exports里面每一个都要声明,比如CommonGroupItem.js有代码如下
module.exports = CommonGroupItem; // 在JS中,每个文件相当于一个模块
ListView知识点
- 使用
1.创建数据源,但还没有给它传递数据
使用state保存数据源,因为数据源的数据改变的时候,需要刷新界面
方法:
ListView.DataSource
:获取ListViewDataSource构造方法
ListViewDataSource构造方法:决定ListView怎么去处理数据,需要传入一个对象
getRowData(dataBlob, sectionID, rowID)
: 怎么获取行数据
getSectionHeaderData(dataBlob, sectionID)
: 怎么获取每一组头部数据
rowHasChanged(prevRowData, nextRowData)
: 决定什么情况行数据才发生改变,当行数据发生改变,就会绘制下一行cell
sectionHeaderHasChanged(prevSectionData, nextSectionData)
: 决定什么情况头部数据才发生改变,当行数据发生改变,就会绘制下一行cell
初始化ListViewDataSource的时候,如果不需要修改提取数据的方式,只需要实现rowHasChanged,告诉什么时候刷新下一行数据
constructor(props) {
super(props);
var ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
}
2.给数据源设置数据
constructor(props) {
super(props);
// 初始化数据源
var ds = new ListView.DataSource({
rowHasChanged:(r1,r2)=>r1!=r2,
sectionHeaderHasChanged:(s1,s2)=> s1 != s2
});
// 设置数据 分组使用:cloneWithRowsAndSections 不分组使用:cloneWithRows
ds = ds.cloneWithRowsAndSections(sectionData)
this.state = {
ds:ds
}
分组样式:只要数据结构如下类型,就会产生分组样式
{ sectionID_1: { rowID_1: rowData1, ... }, ... }
或者:
{ sectionID_1: [ rowData1, rowData2, ... ], ... }
或者:
[ [ rowData1, rowData2, ... ], ... ]
- 如例子:自定义分组ListView:CommonGroupListViewHeader.js
/**
* @providesModule CommonGroupListView
*/
import React, {Component,PropTypes} from 'react'
import
{
AppRegistry,
StyleSheet,
Text,
View,
ListView
}from 'react-native'
import CommonRowCell from 'CommonRowCell'
export default class CommonGroupListView extends Component {
static propTypes = {
groups:PropTypes.array,
groupListViewStyle:PropTypes.oneOfType([PropTypes.number,PropTypes.object]),
imageStyle:PropTypes.oneOfType([PropTypes.number,PropTypes.object]),
titleStyle:PropTypes.oneOfType([PropTypes.number,PropTypes.object]),
subTitleStyle:PropTypes.oneOfType([PropTypes.number,PropTypes.object]),
navigator:PropTypes.object,
renderHeader:PropTypes.func,
renderFooter:PropTypes.func,
}
constructor(props){
super(props);
// 初始化数据源
var ds = new ListView.DataSource({
rowHasChanged:(r1,r2)=>r1!=r2,
sectionHeaderHasChanged:(s1,s2)=> s1 != s2
});
// 处理组模型数组
var groups = this.props.groups;
var sectionData = [];
groups.forEach((groupItem,i)=>{
sectionData.push(groupItem.rowsData);
})
// 设置数据 分组使用:cloneWithRowsAndSections 不分组使用:cloneWithRows
ds = ds.cloneWithRowsAndSections(sectionData)
this.state = {
ds:ds
}
}
render(){
return (
<ListView dataSource={this.state.ds}
renderRow={this._renderRow.bind(this)}
renderSectionHeader={this._renderSectionHeader.bind(this)}
style={this.props.groupListViewStyle}
renderHeader={this.props.renderHeader}
renderFooter={this.props.renderFooter}
/>
)
}
_renderRow(rowData,sectioniD,rowID){
return (
rowData.customData?<rowData.customCellType rowData={rowData} {...this.props}/>:<CommonRowCell rowData={rowData} {...this.props}/>
)
}
_renderSectionHeader(sectionData, sectionID){
// 获取组模型就好了
var groupItem = this.props.groups[sectionID];
return (
<View style={{height:groupItem.sectionHeight}}></View>
)
}
}
var styles = StyleSheet.create({
viewStyle:{
flex:1,
justifyContent:'center',
alignItems:'center'
}
})
- 其他
头部,尾部
_renderHeader() {
return (
<View>
<Text>头部视图</Text>
</View>
)
}
_renderFooter() {
return (
<View>
<Text>尾部视图</Text>
</View>
)
}
点击高亮
_renderRow(rowData, sectionID, rowID, highlightRow) {
return (
<TouchableOpacity onPress={()=>{
highlightRow(sectionID,rowID)
}}>
<View>
<Text>{rowData}</Text>
</View>
</TouchableOpacity>
);
}
分割线
_renderSeparator(sectionID, rowID, adjacentRowHighlighted) {
return (
<View style={{height:1,backgroundColor:'black'}}></View>
)
}
导航栏跳转知识点
- 导航栏跳转以及数据传递 Discover.js中
rowDatas.forEach((rowData,i)=>{
var item = new CommonGroupListViewHeader.CommonRowItem();
item.customData = rowData;
item.customCellType = DiscoverVideoCell;
item.route = { //变量赋值传递数据用于跳转
component:VideoView, // 定义变量说明跳转的视图
videoUri:rowData.video // 定义变量说明参数数据 video是json字段
}
allRowData.push(item);
});
CommonRowCell.js中拥有rowData每一行的数据,拿到rowData中的route就可以push
if(this.props.rowData.route){ // 如果this.props.rowData.route有值,即外界有传递数据
var route = this.props.rowData.route;
route.navigator = this.props.navigator;
this.props.navigator.push(route);
}
VideoView.js
取数据:
this.props.videoUri
所以,相当于
this.props.navigator.push({
component:VideoView,
videoUri:rowData.video
});
- 附上CommonRowCell.js
样式:
/**
* @providesModule CommonRowCell
*/
import React, {Component,PropTypes} from 'react'
// 2.导入常用组件,注册组件,样式组件,View组件,Text组件
import
{
AppRegistry,
StyleSheet,
Text,
View,
TouchableOpacity,
Image,
PixelRatio,
Switch
}from 'react-native'
import Common from 'Common'
export default class CommonRowCell extends Component {
static propTypes = {
rowData:PropTypes.object
}
constructor(props){
super(props);
this.state = {
isOn:false
}
// 判断下当前是否是开关,如果是开关,就不能设置子标题
var className = this.props.rowData.constructor.name;
if (className == 'CommonSwitchRowItem') {
// 判断子标题
if (this.props.rowData.subTitle){
throw '开关模型,不允许设置子标题';
}
}
}
render(){
return (
<TouchableOpacity style={styles.cellStyle}
onPress={()=>{
if(this.props.rowData.clickCell){
this.props.rowData.clickCell();
}
if(this.props.rowData.route){
var route = this.props.rowData.route;
route.navigator = this.props.navigator;
this.props.navigator.push(route);
}
}}
disabled={this.props.rowData.disabled}
>
{/*图片*/}
{this.props.rowData.image?<Image source={{uri:this.props.rowData.image}} style={[styles.imageStyle,this.props.imageStyle]}/>:null}
{/*标题*/}
<Text style={[styles.titleStyle,this.props.titleStyle]}>{this.props.rowData.title}</Text>
{/*子标题 switch*/}
<Text style={[styles.subTitleStyle,this.props.subTitleStyle]}>{this.props.rowData.subTitle}</Text>
{this._renderAccessoryView()}
</TouchableOpacity>
)
}
// 渲染右边辅助视图
_renderAccessoryView(){
// 获取当前对象的构造方法 => 类名
var className = this.props.rowData.constructor.name;
// 判断当前模型属于哪个类
if (className == 'CommonArrowRowItem'){ {/*箭头*/}
return (
<Image source={{uri:'icon_shike_arrow'}} style={styles.arrowStyle}/>
)
} else if (className == 'CommonSwitchRowItem'){ {/*开关*/}
return (
<Switch style={styles.switchStyle}
onValueChange={(newValue)=>{
this.setState({
isOn:newValue
})
}}
value={this.state.isOn}
/>
)
}
{/*什么都不显示*/}
}
}
var styles = StyleSheet.create({
cellStyle:{
flexDirection:'row',
alignItems:'center',
width:Common.screenW,
height:44,
borderBottomColor:'#e5e5e5',
borderBottomWidth:1 / PixelRatio.get(),
backgroundColor:'white'
},
imageStyle:{
width:25,
height:25,
marginLeft:5
},
arrowStyle:{
width:7,
height:12,
position:'absolute',
right:5
},
titleStyle:{
marginLeft:5
},
subTitleStyle:{
marginLeft:5
},
switchStyle:{
position:'absolute',
right:5
},
})