React Native的组件ListView
React Native的组件ListView类似于iOS中的UITableView和UICollectionView,也就是说React Native的组件ListView既可以实现UITableView也可以实现UICollectionView。
ListView的使用方法：
1.首先创建一个ListView.DataSource数据源，然后向他传递一个普通的数据源数组。
2.使用该数据源实例化一个ListView组件，定义一个renderRow回调函数，这个函数会接收数组中的每个数据作为参数，并返回一个可以渲染的组件部分。这个组件部分就是ListView的每一行。
//设置初始值
getInitialState(){
//设置数据源
var ds = new ListView.DataSource({rowHasChanged:(r1,r2) => r1 !== r2}); //当且仅当cell中的任意两行不相等时才重新渲染
//设置返回数据
return{
dataSource:ds.cloneWithRows(Wine)
}
},
render(){
return(
<ListView
dataSource={this.state.dataSource} //数据源
renderRow={this.renderRow} //返回具体的cell,有四个参数 => 1:一条信息 2:分组ID 3:行ID 4:标记是否高亮选中的状态信息.不带()表示参数自传递
/>
);
},
演示代码如下：
/**
* Sample React Native App
* https://github.com/facebook/react-native
* 周少停 listView
* 2016-09-21
*/ import React, { Component } from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,
Image,
ListView
} from 'react-native';
//导入json数据
var Wine = require('./WineJson.json'); //json数组 var Project = React.createClass({
//设置初始值
getInitialState(){
//设置数据源
var ds = new ListView.DataSource({rowHasChanged:(r1,r2) => r1 !== r2}); //当且仅当cell中的任意两行不相等时才重新渲染
//设置返回数据
return{
dataSource:ds.cloneWithRows(Wine)
}
},
render(){
return(
<ListView
dataSource={this.state.dataSource} //数据源
renderRow={this.renderRow} //返回具体的cell,有四个参数 => 1:一条信息 2:分组ID 3:行ID 4:标记是否高亮选中的状态信息.不带()表示参数自传递
/>
);
},
//返回具体的cell
renderRow(rowData,sectionID,rowID,highlightRow){
return(
<View style={styles.cellViewStyle}>
{/*左边的图片*/}
<Image source={{uri:rowData.image}} style={styles.leftImageStyle} />
{/*右边的View*/}
<View style={styles.rightViewStyle}>
<Text style={styles.nameTextStyle}>{rowData.name}</Text>
<Text style={styles.montyTextStyle}>${rowData.money}</Text>
</View>
</View>
);
} }); const styles = StyleSheet.create({
cellViewStyle:{
flexDirection:'row',//主轴方向
borderBottomWidth:1,
borderBottomColor:'cyan'
},
leftImageStyle:{
width:60,
height:60
},
rightViewStyle:{ },
nameTextStyle:{ },
montyTextStyle:{
color:'red',
//距底部2
position:'absolute',
bottom:2
}
}); AppRegistry.registerComponent('Project', () => Project);
涉及到的json数据如下:
[
{
"image":"1.png",
"money":"319",
"name":"酒名1"
},
{
"image":"2.png",
"money":"339",
"name":"酒名2酒名2酒名2酒名22酒名2酒名酒名2"
},
{
"image":"3.png",
"money":"319",
"name":"酒名4"
},
{
"image":"4.png",
"money":"29",
"name":"酒名4"
},
{
"image":"5.png",
"money":"55",
"name":"酒名5"
},
{
"image":"6.png",
"money":"67",
"name":"酒名6"
},
{
"image":"7.png",
"money":"37",
"name":"酒名7"
},
{
"image":"8.png",
"money":"33",
"name":"酒名8"
},
{
"image":"9.png",
"money":"35",
"name":"酒名9"
},
{
"image":"10.png",
"money":"22",
"name":"酒名10"
},
{
"image":"11.png",
"money":"19",
"name":"酒名11"
},
{
"image":"12.png",
"money":"392",
"name":"酒名12"
},
{
"image":"13.png",
"money":"339",
"name":"酒名13"
},
{
"image":"14.png",
"money":"439",
"name":"酒名14"
},
{
"image":"15.png",
"money":"359",
"name":"酒名15"
},
{
"image":"16.png",
"money":"369",
"name":"酒名16"
},
{
"image":"17.png",
"money":"7397",
"name":"酒名17"
},
{
"image":"18.png",
"money":"7397",
"name":"酒名18"
},
{
"image":"19.png",
"money":"7397",
"name":"酒名19"
},
{
"image":"20.png",
"money":"7207",
"name":"酒名20"
},
{
"image":"21.png",
"money":"7397",
"name":"酒名21"
}
]
效果如下：
九宫格演示:
代码:
/**
* Sample React Native App
* https://github.com/facebook/react-native
* 周少停 ListView1
* 2016-09-21
*/ import React, { Component } from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,
Image,
ListView,
AlertIOS,
TouchableOpacity
} from 'react-native';
//导入json
var shareData= require('./shareJson.json');
//Dimentsions
var Dimensions = require('Dimensions');
var screenWidth = Dimensions.get('window').width;
//一些常量设置
var cols = 3; //一行几个cell
var cellWH = 100; //cell的宽高
var vMargin = (screenWidth - cellWH * cols)/ (cols + 1); //cell之间的边距
var hMargin = 20; var Project = React.createClass({
//设置默认值(不可修改)
getDefaultProps(){
return{ }
},
//设置初始值(可以修改)
getInitialState(){
var ds = new ListView.DataSource({rowHasChanged:(r1,r2)=> r1 !== r2});
return{
dataSource : ds.cloneWithRows(shareData.data)
}
},
render(){
return(
<ListView
dataSource={this.state.dataSource}
renderRow={this.renderRow}
contentContainerStyle={styles.listViewStyle}
/>
);
},
//单独的cell
renderRow(rowData){
return(
<TouchableOpacity activeOpacity={0.5} onPress={()=>{this.cellOnclick()}}>
<View style={styles.innerViewStyle}>
<Image source={{uri:rowData.icon}} style={styles.iconStyle}/>
<Text>{rowData.title}</Text>
</View>
</TouchableOpacity>
);
},
cellOnclick(){
AlertIOS.alert("点击了cell")
}
}); const styles = StyleSheet.create({
listViewStyle:{
//改变主轴方向
flexDirection:'row',
//多行显示
flexWrap:'wrap'
},
innerViewStyle:{
width:cellWH,
height:cellWH,
marginLeft:vMargin,
marginTop:hMargin,
alignItems:'center'
},
iconStyle :{
width:80,
height:80
}
}); AppRegistry.registerComponent('Project', () => Project);
涉及到的json:
{
"data":[
{
"icon":"icon1",
"title":"分享1"
},
{
"icon":"icon2",
"title":"分享2"
},
{
"icon":"icon3",
"title":"分享3"
},
{
"icon":"icon4",
"title":"分享5"
},
{
"icon":"icon5",
"title":"分享5"
},
{
"icon":"icon6",
"title":"分享6"
},
{
"icon":"icon7",
"title":"分享7"
},
{
"icon":"icon8",
"title":"分享8"
},
{
"icon":"icon9",
"title":"分享9"
},
{
"icon":"icon10",
"title":"分享10"
}
]
}
效果如下:
带有表头的listView:
代码:
/**
* Sample React Native App
* https://github.com/facebook/react-native
* 周少停 ListView
* 带有分组的ListView 使用cloneWithRowsAndSections设置数据源,三个参数:sectionIDs,rowIDs,dataBlob
* 2016-09-22
*/ import React, { Component } from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,
Image,
ListView,
TouchableOpacity
} from 'react-native';
//导入外部的json数据
var Car = require('./Car.json'); var Project = React.createClass({
//初始化函数 在这里准备数据源
getInitialState(){
var sectionData = (dataBlob,sectionID) => {
return dataBlob[sectionID];
};
var rowData = (dataBlob,sectionID,rowID) => {
return dataBlob[sectionID + ':' + rowID];
};
return{
dataSource:new ListView.DataSource({
getSectionData:sectionData,
getRowData:rowData,
rowHasChanged:(r1,r2) => r1 !== r2,
sectionHeaderHasChanged:(s1,s2) => s1 !== s2
})
}
},
render() {
return (
<ListView
dataSource={this.state.dataSource}
renderRow={this.renderRow}
renderSectionHeader={this.renderSectionHeader}
/>
);
},
//每一行数据
renderRow(rowData){
return(
<TouchableOpacity activeOpacity={0.5}>
<View style={styles.rowStyle}>
<Image source={{uri:rowData.icon}} style={styles.rowImageStyle}/>
<Text style={{marginLeft: 5}}>{rowData.name}</Text>
</View>
</TouchableOpacity>
);
},
//组数据
renderSectionHeader(sectionData,sectionID){
return(
<View style={styles.sectionHeaderStyle}>
<Text style={{color: 'red',marginLeft:5}}>{sectionData}</Text>
</View>
);
},
//做一些复杂的操作:数据请求
componentDidMount() {
this.loadDataFormJson();
},
loadDataFormJson(){
//先取到data数据
var jsonData = Car.data;
//定义一些变量数组用来存值
var dataBlob = {},sectionIDs = [],rowIDs = [],cars = [];
//遍历
for(var i = 0;i<jsonData.length;i++){
//把组号放入sectionIDs数组中
sectionIDs.push(i);
//把组中内容放入dataBlob对象中
dataBlob[i] = jsonData[i].title;
//把组中的每行数据的数组放入cars
cars = jsonData[i].cars;
//先确定rowIDs的第一维
rowIDs[i] = [];
//遍历cars数组,确定rowIDs的第二维
for(var j = 0;j<cars.length;j++){
rowIDs[i].push(j);
//把每一行中的内容放入dataBlob对象中
dataBlob[i+':'+j] = cars[j];
}
}
this.setState({
dataSource:this.state.dataSource.cloneWithRowsAndSections(dataBlob,sectionIDs,rowIDs)
});
}
}); const styles = StyleSheet.create({
rowImageStyle:{
width:70,
height:70
},
rowStyle:{
flexDirection:'row',
alignItems:'center',
padding:10,
borderBottomColor:'#e8e8e8',
borderBottomWidth:0.5
},
sectionHeaderStyle:{
backgroundColor:'#e8e8e8',
height:25,
justifyContent:'center'
}
}); AppRegistry.registerComponent('Project', () => Project);
涉及到的json:
{
"data": [
{
"cars": [
{
"icon": "m_180_100.png",
"name": "AC Schnitzer"
},
{
"icon": "m_92_100.png",
"name": "阿尔法·罗密欧"
},
{
"icon": "m_9_100.png",
"name": "奥迪"
},
{
"icon": "m_97_100.png",
"name": "阿斯顿·马丁"
}
],
"title": "A"
},
{
"cars": [
{
"icon": "m_172_100.png",
"name": "巴博斯"
},
{
"icon": "m_157_100.png",
"name": "宝骏"
},
{
"icon": "m_3_100.png",
"name": "宝马"
},
{
"icon": "m_82_100.png",
"name": "保时捷"
},
{
"icon": "m_163_100.png",
"name": "北京汽车"
},
{
"icon": "m_211_100.png",
"name": "北汽幻速"
},
{
"icon": "m_168_100.png",
"name": "北汽威旺"
},
{
"icon": "m_14_100.png",
"name": "北汽制造"
},
{
"icon": "m_2_100.png",
"name": "奔驰"
},
{
"icon": "m_59_100.png",
"name": "奔腾"
},
{
"icon": "m_26_100.png",
"name": "本田"
},
{
"icon": "m_5_100.png",
"name": "标致"
},
{
"icon": "m_127_100.png",
"name": "别克"
},
{
"icon": "m_85_100.png",
"name": "宾利"
},
{
"icon": "m_15_100.png",
"name": "比亚迪"
},
{
"icon": "m_135_100.png",
"name": "布加迪"
}
],
"title": "B"
},
{
"cars": [
{
"icon": "m_129_100.png",
"name": "昌河"
}
],
"title": "C"
},
{
"cars": [
{
"icon": "m_113_100.png",
"name": "道奇"
},
{
"icon": "m_165_100.png",
"name": "大通"
},
{
"icon": "m_8_100.png",
"name": "大众"
},
{
"icon": "m_27_100.png",
"name": "东风"
},
{
"icon": "m_197_100.png",
"name": "东风风度"
},
{
"icon": "m_141_100.png",
"name": "东风风神"
},
{
"icon": "m_115_100.png",
"name": "东风风行"
},
{
"icon": "m_205_100.png",
"name": "东风小康"
},
{
"icon": "m_29_100.png",
"name": "东南"
},
{
"icon": "m_179_100.png",
"name": "DS"
}
],
"title": "D"
},
{
"cars": [
{
"icon": "m_91_100.png",
"name": "法拉利"
},
{
"icon": "m_199_100.png",
"name": "飞驰商务车"
},
{
"icon": "m_164_100.png",
"name": "菲斯克"
},
{
"icon": "m_40_100.png",
"name": "菲亚特"
},
{
"icon": "m_7_100.png",
"name": "丰田"
},
{
"icon": "m_67_100.png",
"name": "福迪"
},
{
"icon": "m_190_100.png",
"name": "弗那萨利"
},
{
"icon": "m_208_100.png",
"name": "福汽启腾"
},
{
"icon": "m_17_100.png",
"name": "福特"
},
{
"icon": "m_128_100.png",
"name": "福田"
}
],
"title": "F"
},
{
"cars": [
{
"icon": "m_109_100.png",
"name": "GMC"
},
{
"icon": "m_110_100.png",
"name": "光冈"
},
{
"icon": "m_147_100.png",
"name": "广汽"
},
{
"icon": "m_63_100.png",
"name": "广汽吉奥"
},
{
"icon": "m_133_100.png",
"name": "广汽日野"
},
{
"icon": "m_182_100.png",
"name": "观致汽车"
}
],
"title": "G"
},
{
"cars": [
{
"icon": "m_31_100.png",
"name": "哈飞"
},
{
"icon": "m_196_100.png",
"name": "哈弗"
},
{
"icon": "m_170_100.png",
"name": "海格"
},
{
"icon": "m_32_100.png",
"name": "海马"
},
{
"icon": "m_149_100.png",
"name": "海马商用车"
},
{
"icon": "m_181_100.png",
"name": "恒天汽车"
},
{
"icon": "m_58_100.png",
"name": "红旗"
},
{
"icon": "m_52_100.png",
"name": "黄海"
},
{
"icon": "m_112_100.png",
"name": "华泰"
},
{
"icon": "m_45_100.png",
"name": "汇众"
}
],
"title": "H"
},
{
"cars": [
{
"icon": "m_35_100.png",
"name": "江淮"
},
{
"icon": "m_37_100.png",
"name": "江铃"
},
{
"icon": "m_38_100.png",
"name": "江南"
},
{
"icon": "m_98_100.png",
"name": "捷豹"
},
{
"icon": "m_143_100.png",
"name": "吉利帝豪"
},
{
"icon": "m_144_100.png",
"name": "吉利全球鹰"
},
{
"icon": "m_148_100.png",
"name": "吉利英伦"
},
{
"icon": "m_39_100.png",
"name": "金杯"
},
{
"icon": "m_57_100.png",
"name": "金龙联合"
},
{
"icon": "m_161_100.png",
"name": "金旅客车"
},
{
"icon": "m_152_100.png",
"name": "九龙"
},
{
"icon": "m_4_100.png",
"name": "Jeep"
}
],
"title": "J"
},
{
"cars": [
{
"icon": "m_188_100.png",
"name": "卡尔森"
},
{
"icon": "m_107_100.png",
"name": "凯迪拉克"
},
{
"icon": "m_150_100.png",
"name": "开瑞"
},
{
"icon": "m_51_100.png",
"name": "克莱斯勒"
},
{
"icon": "m_145_100.png",
"name": "科尼塞克"
},
{
"icon": "m_212_100.png",
"name": "KTM"
}
],
"title": "K"
},
{
"cars": [
{
"icon": "m_86_100.png",
"name": "兰博基尼"
},
{
"icon": "m_200_100.png",
"name": "蓝海房车"
},
{
"icon": "m_80_100.png",
"name": "劳斯莱斯"
},
{
"icon": "m_94_100.png",
"name": "雷克萨斯"
},
{
"icon": "m_99_100.png",
"name": "雷诺"
},
{
"icon": "m_146_100.png",
"name": "莲花"
},
{
"icon": "m_153_100.png",
"name": "猎豹汽车"
},
{
"icon": "m_76_100.png",
"name": "力帆"
},
{
"icon": "m_16_100.png",
"name": "铃木"
},
{
"icon": "m_166_100.png",
"name": "理念"
},
{
"icon": "m_95_100.png",
"name": "林肯"
},
{
"icon": "m_36_100.png",
"name": "陆风"
},
{
"icon": "m_96_100.png",
"name": "路虎"
},
{
"icon": "m_83_100.png",
"name": "路特斯"
}
],
"title": "L"
},
{
"cars": [
{
"icon": "m_183_100.png",
"name": "迈凯伦"
},
{
"icon": "m_93_100.png",
"name": "玛莎拉蒂"
},
{
"icon": "m_18_100.png",
"name": "马自达"
},
{
"icon": "m_79_100.png",
"name": "MG"
},
{
"icon": "m_81_100.png",
"name": "MINI"
},
{
"icon": "m_201_100.png",
"name": "摩根"
}
],
"title": "M"
},
{
"cars": [
{
"icon": "m_155_100.png",
"name": "纳智捷"
}
],
"title": "N"
},
{
"cars": [
{
"icon": "m_104_100.png",
"name": "欧宝"
},
{
"icon": "m_84_100.png",
"name": "讴歌"
},
{
"icon": "m_171_100.png",
"name": "欧朗"
}
],
"title": "O"
},
{
"cars": [
{
"icon": "m_156_100.png",
"name": "启辰"
},
{
"icon": "m_43_100.png",
"name": "庆铃"
},
{
"icon": "m_42_100.png",
"name": "奇瑞"
},
{
"icon": "m_28_100.png",
"name": "起亚"
}
],
"title": "Q"
},
{
"cars": [
{
"icon": "m_30_100.png",
"name": "日产"
},
{
"icon": "m_78_100.png",
"name": "荣威"
},
{
"icon": "m_142_100.png",
"name": "瑞麒"
}
],
"title": "R"
},
{
"cars": [
{
"icon": "m_25_100.png",
"name": "三菱"
},
{
"icon": "m_209_100.png",
"name": "山姆"
},
{
"icon": "m_195_100.png",
"name": "绅宝"
},
{
"icon": "m_50_100.png",
"name": "双环"
},
{
"icon": "m_102_100.png",
"name": "双龙"
},
{
"icon": "m_111_100.png",
"name": "斯巴鲁"
},
{
"icon": "m_10_100.png",
"name": "斯柯达"
},
{
"icon": "m_89_100.png",
"name": "smart"
}
],
"title": "S"
},
{
"cars": [
{
"icon": "m_202_100.png",
"name": "泰卡特"
},
{
"icon": "m_189_100.png",
"name": "特斯拉"
}
],
"title": "T"
},
{
"cars": [
{
"icon": "m_140_100.png",
"name": "威麟"
},
{
"icon": "m_186_100.png",
"name": "威兹曼"
},
{
"icon": "m_19_100.png",
"name": "沃尔沃"
},
{
"icon": "m_48_100.png",
"name": "五菱"
}
],
"title": "W"
},
{
"cars": [
{
"icon": "m_13_100.png",
"name": "现代"
},
{
"icon": "m_174_100.png",
"name": "星客特"
},
{
"icon": "m_71_100.png",
"name": "新凯"
},
{
"icon": "m_87_100.png",
"name": "西雅特"
},
{
"icon": "m_49_100.png",
"name": "雪佛兰"
},
{
"icon": "m_6_100.png",
"name": "雪铁龙"
}
],
"title": "X"
},
{
"cars": [
{
"icon": "m_194_100.png",
"name": "扬州亚星客车"
},
{
"icon": "m_138_100.png",
"name": "野马汽车"
},
{
"icon": "m_100_100.png",
"name": "英菲尼迪"
},
{
"icon": "m_53_100.png",
"name": "一汽"
},
{
"icon": "m_41_100.png",
"name": "依维柯"
},
{
"icon": "m_75_100.png",
"name": "永源"
}
],
"title": "Y"
},
{
"cars": [
{
"icon": "m_136_100.png",
"name": "长安轿车"
},
{
"icon": "m_159_100.png",
"name": "长安商用"
},
{
"icon": "m_21_100.png",
"name": "长城"
},
{
"icon": "m_203_100.png",
"name": "之诺"
},
{
"icon": "m_60_100.png",
"name": "中华"
},
{
"icon": "m_167_100.png",
"name": "中欧"
},
{
"icon": "m_77_100.png",
"name": "众泰"
},
{
"icon": "m_204_100.png",
"name": "中通客车"
},
{
"icon": "m_33_100.png",
"name": "中兴"
}
],
"title": "Z"
}
]
}
效果如下:
完整源码下载：https://github.com/pheromone/React-Native-1
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