我正在尝试根据配置选项动态创建一些组件。更具体地说,我想拥有一些工具栏,其中可能包含不同的"工具栏项目"。
根据角度指南:https://angular.io/docs/ts/latest/cookbook/dynamic-component-loader.html我创建了专门的指令
@Directive({
selector: '[mte-toolbar-item-host]'
})
export class ToolbarItemDirective {
constructor(public viewContainerRef: ViewContainerRef) {
}
}
将用于指示组件的"注入"点。
我有主要ToolbarComponent
@Component({
selector: "mte-toolbar",
templateUrl: "./toolbar.component.html",
styleUrls: ["./toolbar.component.css"],
providers: [ToolbarService]
})
export class ToolbarComponent implements AfterViewInit {
toolbar: Toolbar;
@ViewChild(ToolbarItemDirective)
toolbarItemHost: ToolbarItemDirective;
constructor(private toolbarService: ToolbarService, private componentFactoryResolver: ComponentFactoryResolver) {
}
ngAfterViewInit(): void {
this.toolbar = new Toolbar(this.toolbarService.getToolbarItems());
for (let i in this.toolbar.items) {
let toolbarItem = this.toolbar.items[i];
let toolbarItemFactory = this.componentFactoryResolver.resolveComponentFactory(toolbarItem.componentType);
let componentRef = this.toolbarItemHost.viewContainerRef.createComponent(toolbarItemFactory);
componentRef.instance.toolbarItem = toolbarItem;
}
}
}
使用适当的模板
<ul class="nav nav-pills">
<li role="presentation" mte-toolbar-item-host></li>
</ul>
目前,toolbarService
正在返回以下组件列表:
export const DEFAULT_TOOLBAR_ITEMS: ToolbarItem[] = [
new GlyphToolbarItem(GlyphToolbarItemComponent, "example-component-id-1", null, "glyphicon-log-in"),
new GlyphToolbarItem(GlyphToolbarItemComponent, "example-component-id-2", null, "glyphicon-floppy-remove"),
new GlyphToolbarItem(GlyphToolbarItemComponent, "example-component-id-3", null, "glyphicon-log-in"),
new GlyphToolbarItem(GlyphToolbarItemComponent, "example-component-id-4", null, "glyphicon-paste")
];
@Injectable()
export class ToolbarService {
getToolbarItems(): ToolbarItem[] {
return DEFAULT_TOOLBAR_ITEMS;
}
}
GlyphToolbarItem
:
export class GlyphToolbarItem extends ToolbarItem {
glyphIcon: string;
constructor(componentType: Type<any>, id: string, command: AbstractCommand, glyphIcon: string) {
super(componentType, id, command);
this.glyphIcon = glyphIcon;
}
}
GlyphToolbarItemComponent
:
@Component({
selector: '[mte-glyph-toolbar-item]',
templateUrl: './glyph-toolbar-item.component.html'
})
export class GlyphToolbarItemComponent {
toolbarItem: ToolbarItem;
}
它的模板
<a class="btn btn-default btn-sm glyphicon {{toolbarItem.glyphIcon}}"></a>
我期望收到类似的东西:
<ul _ngcontent-c2="" class="nav nav-pills"><!---->
<li role="presentation" mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-log-in"></a>
</li>
<li role="presentation" mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-floppy-remove"></a>
</li>
<li role="presentation" mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-log-in"></a>
</li>
<li role="presentation" mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-paste"></a>
</li>
</ul>
,但是我已经收到了用<div>
包装的动态组件:
<ul _ngcontent-c2="" class="nav nav-pills"><!---->
<div mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-log-in"></a>
</div>
<div mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-floppy-remove"></a>
</div>
<div mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-log-in"></a>
</div>
<div mte-glyph-toolbar-item="" ng-version="4.0.3">
<a class="btn btn-default btn-sm glyphicon glyphicon-paste"></a>
</div>
为什么我会收到用<div>
而不是<li>
元素包裹的动态组件(似乎完全忽略了(?这是实现此目标的正确方法吗?
我认为您必须要glyphtoolbaritemcomponent:
@Component({
selector: 'li[mte-glyph-toolbar-item]',
template: '<a class="btn btn-default btn-sm glyphicon {{toolbarItem.glyphIcon}}"></a>'
})
export class GlyphToolbarItemComponent {
@HostBinding('attr.role') role ="presentation";
toolbarItem: ToolbarItem;
}
并删除空的li 移动mte-toolbar-item-inost to ul> ng-container
<ul class="nav nav-pills">
<ng-container mte-toolbar-item-host></ng-container>
</ul>
我也认为Angular不会喜欢您在Ngafterviewinit中创建这些组件
我创建了https://plnkr.co/edit/8cjlzooo1oh2cwydxbsn?p=info
您从中获取 ViewContainerRef
元素的元素无关紧要。createComponent
将添加一个兄弟姐妹,并使用动态创建的组件的选择器作为元素。因为默认情况下,选择器<div>
中没有给出任何元素。
如果您从
更改选择器selector: '[mte-glyph-toolbar-item]',
to
selector: 'li[mte-glyph-toolbar-item]',
或
selector: 'li',
您将获得<li>
元素。