这里用到的其实是一个新的场景页面 而不是像原生的组件一样 悬浮在页面之上,它实现的原理是从新绘制一个带弹出框样式的页面,除了弹出框之外都是灰色的,且将要显示弹出框页面的布局完全移植过来。
这里通过 BackAndroid API 实现了点击返回键 自定义对话框消失的效果
BackAndroid API 的工作机制是,当挂接多个Listener 后,用户按下返回键时,多个Listener 都会监听到返回键按下事件,并且他们的处理函数都会被执行,执行的顺序是天津的顺序,这些处理函数都执行后,只要有一个处理函数返回了true(表示返回键被按下事件已经被处理),返回键被按下事件就不会交个Android框架处理,也就是说,应用程序没有 办法退出。
程序的入口文件 index.android.js
import React,{Component} from 'react';
import {AppRegistry,Navigator,BackAndroid,Alert} from 'react-native';
import RegisterLeaft from './RegisterLeaft';
import WaitingLeaft from './WaitingLeaft';
export default class NavigatorModule extends Component {
constructor (props) {
super(props)
this.handleBack = this._handleBack.bind(this) // 返回一个绑定好this的方法并存储于当前实例中
}
configureScene(router){
return Navigator.SceneConfigs.FadeAndroid;
}
renderScene(router,navigator){
switch(router.name) {
case "register":
return <RegisterLeaft navigator={navigator}/>
case "waiting" :
return <WaitingLeaft
phoneNumber = {router.phoneNumber}
userPW = {router.userPW}
navigator={navigator}
/>
}
}
componentDidMount() {
BackAndroid.addEventListener("NoviModuleListener",this.handleBack);
}
_handleBack () {
const nav=this.navigator;
if(nav!=null){
const routers=nav.getCurrentRoutes();
if(routers.length>1){
nav.pop();
return true;
}
}
return false;
}
componentWillUnount(){
BackAndroid.removeEventListener("NoviModuleListener",this.handleBack);
}
render(){
return(
<Navigator
ref={nav => {this.navigator=nav}}
initialRoute={{name:'register'}}
configureScene={this.configureScene}
renderScene ={(route,navigator) =>this.renderScene(route,navigator)}
/>
);
}
}
AppRegistry.registerComponent('AwesomeProject',() => NavigatorModule);
对话框组件 ConfirmDialog.js
import React,View,Text,StyleSheet,Alert} from 'react-native';
let Dimensions = require('Dimensions');
let totalWidth = Dimensions.get('window').width;
let totalHeight = Dimensions.get('window').height;
export default class ConfirmDialog extends Component{
constructor (props) {
super(props)
this.newHandleBack = this._newHandleBack.bind(this) // 返回一个绑定好this的方法并存储于当前实例中
}
render(){
return(
<View style={styles.ConfirmContent}>
<View style={styles.dialogStyle}>
<Text style={styles.textPrompt}>
{this.props.promptToUser}
</Text>
<Text style={styles.yesButton}
onPress = {()=>{this.props.userConfirmed()}}
>
{'\r\n'}确定
</Text>
<Text style={styles.cancelButton}
onPress = {()=>{this.props.userCanceled()}}
>
{'\r\n'}取消
</Text>
</View>
</View>
);
}
componentDidMount() {
let amIStillAlive = this.props.amIStillAlive;
let navigator =this.props.navigator;
BackAndroid.addEventListener("ConfirmDialogListener",this.newHandleBack);
}
componentWillUnmount(){
BackAndroid.removeEventListener("ConfirmDialogListener",this.newHandleBack);
}
_newHandleBack () {
let amIStillAlive = this.props.amIStillAlive();
let navigator =this.props.navigator;
if(amIStillAlive==true){
this.props.userCanceled();
return true;
}
return false;
}
}
let styles = StyleSheet.create({
ConfirmContent:{
position:"absolute",top:0,width:totalWidth,height:totalHeight,backgroundColor:'rgba(52,52,0.5)'
},dialogStyle:{
position:"absolute",top:totalHeight * 0.4,left:totalWidth / 10,width:totalWidth * 0.8,height:totalHeight * 0.3,backgroundColor:'white'
},textPrompt:{
position:'absolute',top:10,left:10,fontSize:20,color:'black'
},yesButton:{
position:'absolute',bottom:10,width:totalWidth*0.35,height:totalHeight*0.1,backgroundColor:'gray',color:'white',textAlign:'center'
},cancelButton:{
position:'absolute',right:10,textAlign:'center'
}
}
);
注册页面 RegisterLeaft.js
import React,TextInput,Alert,Navigator} from 'react-native';
import ConfirmDialog from './ConfirmDialog';
let Dimensions = require('Dimensions');
let totalWidth = Dimensions.get('window').width;
let leftStartPoint = totalWidth * 0.1;
let componentWidth = totalWidth * 0.8;
export default class RegisterLeaft extends Component {
constructor(props) {
super(props);
this.state={
inputedNum:"",inputedPW:"",needToConfirm:false
};
}
render() {
if(this.state.needToConfirm==true)
return this.renderWithDialog();
return (
<View style = {styles.container} >
<TextInput style = {styles.numberInputStyle}
placeholder = {'请输入手机号:'}
onChangeText={(inputedNum)=>this.setState({inputedNum})}
/>
<Text style = {styles.textPromptStyle} >
您输入的手机号:{this.state.inputedNum}
</Text >
<TextInput style = {styles.passwordInputStyle}
placeholder = { '请输入密码' }
onChangeText={(inputedPW)=>this.setState({inputedPW})}
password = 'true'
/>
<Text style = {styles.bigTextPrompt}
onPress = {()=>{this.userPressConfirm()}}
>
确定
</Text>
</View>);
}
renderWithDialog(){
return (
<View style = {styles.container} >
<TextInput style = {styles.numberInputStyle}
placeholder = {'请输入手机号:'}
onChangeText={(inputedNum)=>this.setState({inputedNum})}
/>
<Text style = {styles.textPromptStyle} >
您输入的手机号:{this.state.inputedNum}
</Text >
<TextInput style = {styles.passwordInputStyle}
placeholder = {'请输入密码'}
onChangeText={(inputedPW)=>this.setState({inputedPW})}
password = 'true'
/>
<Text style = {styles.bigTextPrompt}
onPress ={()=>{this.userPressConfirm()}}
>
确定
</Text>
<ConfirmDialog
userConfirmed={()=>{this.userConfirmed()}}
userCanceled = {()=>{this.userCanceled()}}
amIStillAlive= {()=>{this.tellConfirmDialogItsStatus()}}
promptToUser ={'使用'+this.state.inputedNum+'号码登录?'}
>
</ConfirmDialog>
</View>);
}
userPressConfirm(){
this.setState({needToConfirm:true});
}
userCanceled(){
this.setState({needToConfirm:false});
}
userConfirmed(){
this.setState({needToConfirm:true});
this.props.navigator.push({
phoneNmuber:this.state.inputedNum,userPW:this.state.inputedPW,name:"waiting"
});
}
tellConfirmDialogItsStatus(){
return this.state.needToConfirm;
}
}
let styles = StyleSheet.create({
container: {
flex: 1,backgroundColor: 'white'
},numberInputStyle: {
top: 20,left: leftStartPoint,width: componentWidth,backgroundColor: 'gray',fontSize: 20
},textPromptStyle: {
top: 30,fontSize: 20
},passwordInputStyle: {
top: 50,bigTextPrompt: {
top: 70,color: 'white',textAlign: 'center',fontSize: 40
}
});
等待页面 WaitingLeaft.js
import React,TextInput} from 'react-native'; export default class WaitingLeaft extends Component{ render() { return ( <View style = {styles.container} > <Text style = {styles.textPromptStyle} > 注册使用手机号码:{this.props.phoneNumber} </Text > <Text style = {styles.textPromptStyle} > 注册使用密码:{this.props.userPW} </Text > <Text style = {styles.bigTextPrompt} onPress = {this.goBack.bind(this)} > 返回 </Text> </View>); } goBack(){ this.props.navigator.push( { name:"register" } ); } } let styles = StyleSheet.create({ container: { flex: 1,justifyContent:'center',alignItems:'center',backgroundColor:'#F5FCFF' },textPromptStyle: { fontSize: 20 },bigTextPrompt: { width: 300,fontSize: 60 } });
原文链接:https://www.f2er.com/react/304514.html