窗口小部件由自定义元素(@ angular / elements)制成,并嵌入通用角度中。我的操作方式是在index.html中添加脚本标签(angularElements.js),并将自定义标签添加到组件中。
在有角度的非ssr中效果很好,但在ssr模式下会引发异常。 错误是自定义元素模块的构造函数被调用两次,并引发DOMException。
下面的代码是自定义元素模块的示例代码。
declare var require: any;
@NgModule({
})
export class WidgetModule implements DoBootstrap {
constructor(
private injector: Injector,
@Inject(PLATFORM_ID) private platformId: Object
) {
}
defineCustomElements(fn: any, name: string, component: Type<any>) {
if ( isPlatformBrowser(this.platformId) ) {
window.customElements.define(name, fn(component, {injector: this.injector}));
}
}
ngDoBootstrap() {
console.log('constructor of widget is called.....');
if ( isPlatformBrowser(this.platformId) ) {
const { createCustomElement } = require('@angular/elements');
this.defineCustomElements(createCustomElement, 'widget-main-schedule', MainScheduleComponent);
}
}
}
这是角度通用语言中的精巧代码。
<body>
<app-root></app-root>
<script type="text/javascript" src="http://localhost/widgets/angularElements.js"></script>
</body>
</html>
这是小部件示例
<div #main_schedule class="main-schedule">
<h2>Competition Schedule</h2>
<!-- this is widget -->
<widget-main-schedule></widget-main-schedule>
</div>
下面是浏览器控制台中的错误消息。
ERROR DOMException: Failed to execute 'define' on 'CustomElementRegistry': this name has already been used with this registry
at CustomElementRegistry.e.(anonymous function) [as define] (http://localhost/widgets/angularElements.js:2:35267)
at t.defineCustomElements (http://localhost/widgets/angularElements.js:4:210330)
at t.ngDoBootstrap (http://localhost/widgets/angularElements.js:4:210525)
答案 0 :(得分:0)
我遇到了类似的问题,我的解决方案是在定义customElement之前进行检查。在您的代码中,将其更改为:
defineCustomElements(fn: any, name: string, component: Type<any>) {
if ( isPlatformBrowser(this.platformId) ) {
if (!window.customElements.get(name)) {
window.customElements.define(name, fn(component, {injector: this.injector}));
}
}
}
应该为您消除该错误。