对子组件执行方法

Question

我有一个父组件和一个子组件.我希望能够从父组件上的某个方法调用子组件上的一些子方法.有没有办法获得父类的子组件实例的引用并调用子的公共方法？

@Component({
    selector: 'child-component'
})
@View({
    template: `<div>child</div>`
})
class ChildComponent{
    constructor () {

    }

    doChildEvent () {
        //  some child event
    }
}

@Component({
    selector: 'parent-component'
})
@View({
    template: `
        <child-component #child></child-component>
    `,
    directives: [
        ChildComponent
    ]
})
class ParentComponent {
    private child:ChildComponent;

    constructor () {

    }

    onSomeParentEvent() {
        this.child.doChildEvent();
    }
}

我尝试在模板中对子进行哈希并在类中引用它但没有成功.

Answer 1

这ViewChild是为了什么:

//don't forget to import ViewChild

class ParentComponent {
    @ViewChild(ChildComponent) private child:ChildComponent;

    constructor () {
       //this.child is undefined because constructor is called before AfterViewInit
    }

    onSomeParentEvent() {
        //this.child contains the reference you're looking for 
        this.child.doChildEvent();
    }
}

假设在onSomeParentEvent被激活之后AfterViewInit, this.child将包含对子组件的引用.