Angular 2 中的更改检测
Change detection in Angular 2
我正在将 angular 1 和 angular 2 整合在一起。因此我有 angular 1 个控制器和服务以及 angular 2 个组件。这些对于数据检索和存储都很好,反之亦然。下面是我的 html 页面。
<body>
<h3>Angular 1 service</h3>
<div ng-controller="MainController">
<input ng-model="username" />
<button ng-click="setUser()">Set User</button>
<button ng-click="getUser()">Get User</button>
<div>User in service : {{user}}</div>
</div>
<hr>
<h3>Angular 2 component uses Angular 1 service</h3>
<user-section></user-section>
</body>
控制器如下,
myApp.controller('MainController', function ($scope, UserService) {
$scope.getUsers = function () {
UserService.setUser($scope.username);
window.location = './angular2.html'
};
$scope.setUser = function () {
UserService.setUser($scope.username);
$scope.user = $scope.username;
};
$scope.getUser = function () {
$scope.user = UserService.getUser();
};
});
服务如下,
function UserService(){
this.user = "default";
}
UserService.prototype.getUsers = function(){
var users = ['user1', 'user2', 'user3'];
return users;
}
UserService.prototype.setUser = function(usr){
this.user = usr;
}
UserService.prototype.getUser = function(){
return this.user;
}
angular2个分量如下,
import {Component, Inject} from 'angular2/core';
@Component({
selector: 'user-section',
templateUrl: '<div>
<input [(ngModel)]="username" />
<button (click)="setUser()">Set User</button>
<button (click)="getUser()">Get User</button>
<button (click)="getUsers()">Get Users</button>
<br/>
<ul>
<li *ngFor="#userId of users">{{userId}}</li>
</ul>
<div>User in service : {{user}}</div>
</div>'
})
export class UserSection {
constructor(@Inject('UserService') userService:UserService) {
this.users = [];
this.username = '';
this._UserService = userService;
}
getUsers(){
this.users = this._UserService.getUsers();
}
setUser(){
this._UserService.setUser(this.username);
}
getUser(){
this.user = this._UserService.getUser();
}
}
需要始终为 angular 2 触发事件(getUser)以从 angular 1 中获取名称。工作 plunker https://plnkr.co/edit/fYbIeJUUY7Xst7GEoi2v?p=preview
每当 angular 1 输入更改时,我想更新 angular 2 模型。有没有办法做到这一点? angular 2 中有监听器,但我不知道如何让他们监听 angular 1 服务。
我猜你应该看看 Angular2 中的 ngDoCheck 和 OnChanges 生命周期挂钩以及 Angular1 中的 $apply。
使用 $apply 你的控制器修改如下
var myApp = angular.module("hybridExampleApp", []);
//define as Angular 1 service
myApp.service('UserService', UserService);
myApp.controller('MainController', function ($scope, UserService) {
$scope.$watch('username',function(){
$scope.setUser();
});
$scope.getUsers = function () {
UserService.setUser($scope.username);
window.location = './angular2.html'
};
$scope.setUser = function () {
UserService.setUser($scope.username);
$scope.user = $scope.username;
};
$scope.getUser = function () {
$scope.user = UserService.getUser();
};
});
使用 ngDoCheck 你的 user.section.component.ts 修改如下
import {Component, Inject,ChangeDetectionStrategy,ngDoCheck,ngOnChanges} from 'angular2/core';
@Component({
selector: 'user-section',
templateUrl: './src/ng2-component/user.section.tpl.html',
changeDetection: ChangeDetectionStrategy.OnPush
})
export class UserSection implements ngDoCheck, ngOnChanges{
username123:number;
constructor(@Inject('UserService') userService:UserService) {
this.users = [];
this.username = '';
this.user=0;
this._UserService = userService;
}
ngOnChanges(){
console.log('adfkjna');
}
getUsers():void{
this.users = this._UserService.getUsers();
}
setUser():void{
this._UserService.setUser(this.username);
}
getUser():void{
this.user = this._UserService.getUser();
}
ngDoCheck(){
this.user = this._UserService.getUser();
this.getUser();
console.log(this.user);
}
}
我的代码完全记录 angular 1 中的用户名更改,但我不明白为什么它没有将它绑定到 UI.
LIVE DEMO 你更新的 plunker。
我正在将 angular 1 和 angular 2 整合在一起。因此我有 angular 1 个控制器和服务以及 angular 2 个组件。这些对于数据检索和存储都很好,反之亦然。下面是我的 html 页面。
<body>
<h3>Angular 1 service</h3>
<div ng-controller="MainController">
<input ng-model="username" />
<button ng-click="setUser()">Set User</button>
<button ng-click="getUser()">Get User</button>
<div>User in service : {{user}}</div>
</div>
<hr>
<h3>Angular 2 component uses Angular 1 service</h3>
<user-section></user-section>
</body>
控制器如下,
myApp.controller('MainController', function ($scope, UserService) {
$scope.getUsers = function () {
UserService.setUser($scope.username);
window.location = './angular2.html'
};
$scope.setUser = function () {
UserService.setUser($scope.username);
$scope.user = $scope.username;
};
$scope.getUser = function () {
$scope.user = UserService.getUser();
};
});
服务如下,
function UserService(){
this.user = "default";
}
UserService.prototype.getUsers = function(){
var users = ['user1', 'user2', 'user3'];
return users;
}
UserService.prototype.setUser = function(usr){
this.user = usr;
}
UserService.prototype.getUser = function(){
return this.user;
}
angular2个分量如下,
import {Component, Inject} from 'angular2/core';
@Component({
selector: 'user-section',
templateUrl: '<div>
<input [(ngModel)]="username" />
<button (click)="setUser()">Set User</button>
<button (click)="getUser()">Get User</button>
<button (click)="getUsers()">Get Users</button>
<br/>
<ul>
<li *ngFor="#userId of users">{{userId}}</li>
</ul>
<div>User in service : {{user}}</div>
</div>'
})
export class UserSection {
constructor(@Inject('UserService') userService:UserService) {
this.users = [];
this.username = '';
this._UserService = userService;
}
getUsers(){
this.users = this._UserService.getUsers();
}
setUser(){
this._UserService.setUser(this.username);
}
getUser(){
this.user = this._UserService.getUser();
}
}
需要始终为 angular 2 触发事件(getUser)以从 angular 1 中获取名称。工作 plunker https://plnkr.co/edit/fYbIeJUUY7Xst7GEoi2v?p=preview 每当 angular 1 输入更改时,我想更新 angular 2 模型。有没有办法做到这一点? angular 2 中有监听器,但我不知道如何让他们监听 angular 1 服务。
我猜你应该看看 Angular2 中的 ngDoCheck 和 OnChanges 生命周期挂钩以及 Angular1 中的 $apply。
使用 $apply 你的控制器修改如下
var myApp = angular.module("hybridExampleApp", []);
//define as Angular 1 service
myApp.service('UserService', UserService);
myApp.controller('MainController', function ($scope, UserService) {
$scope.$watch('username',function(){
$scope.setUser();
});
$scope.getUsers = function () {
UserService.setUser($scope.username);
window.location = './angular2.html'
};
$scope.setUser = function () {
UserService.setUser($scope.username);
$scope.user = $scope.username;
};
$scope.getUser = function () {
$scope.user = UserService.getUser();
};
});
使用 ngDoCheck 你的 user.section.component.ts 修改如下
import {Component, Inject,ChangeDetectionStrategy,ngDoCheck,ngOnChanges} from 'angular2/core';
@Component({
selector: 'user-section',
templateUrl: './src/ng2-component/user.section.tpl.html',
changeDetection: ChangeDetectionStrategy.OnPush
})
export class UserSection implements ngDoCheck, ngOnChanges{
username123:number;
constructor(@Inject('UserService') userService:UserService) {
this.users = [];
this.username = '';
this.user=0;
this._UserService = userService;
}
ngOnChanges(){
console.log('adfkjna');
}
getUsers():void{
this.users = this._UserService.getUsers();
}
setUser():void{
this._UserService.setUser(this.username);
}
getUser():void{
this.user = this._UserService.getUser();
}
ngDoCheck(){
this.user = this._UserService.getUser();
this.getUser();
console.log(this.user);
}
}
我的代码完全记录 angular 1 中的用户名更改,但我不明白为什么它没有将它绑定到 UI.
LIVE DEMO 你更新的 plunker。