angular - 模糊事件未在 Angular 分量上触发

Question

我正在尝试获得一种 react 形式来正确处理模糊事件，但它似乎无法对模糊做出正确 react 。

import { Component, HostListener, HostBinding } from '@angular/core';

@Component({
  selector: 'app-combo-box-basic',
  templateUrl: './combo-box-basic.html'
})
export class ComboBoxBasic {

  @HostListener('blur', ['$event.target']) onBlur(target) {
    console.log(`onBlur(): ${new Date()} - ${JSON.stringify(target)}`);
  }
}

<div class="btn-group mr-3">
  <input (blur)="onBlur($event.target)" type="text" class="btn btn-outline-success">
  <div class="btn-group" ngbDropdown role="group" aria-label="Button group with nested dropdown">
    <button (blur)="onBlur($event.target)" class="btn btn-outline-primary" ngbDropdownToggle></button>
    <div class="dropdown-menu" ngbDropdownMenu>
      <button class="dropdown-item">One</button>
      <button class="dropdown-item">Two</button>
      <button class="dropdown-item">Four!</button>
    </div>
  </div>
</div>

Answer 1

经过大量搜索和试验后，我发现了一些需要让它正常工作的项目。 A fully functional demo can be found here

1. 外部元素必须具有:tabindex="0" 以便它可以聚焦。这是通过以下方式实现的:@HostBinding('attr.tabindex') tabindex = '0';

2. 为模糊事件添加一个 HostListener 将捕获外部组件:@HostListener('blur', ['$event.target']) onBlur(target) { ... }

3. 您仍然需要捕获内部组件的模糊事件，以便点击进入和退出仍会触发。 (blur)="onBlur($event.target)"

import { Component, HostListener, HostBinding } from '@angular/core';

@Component({
  selector: 'app-combo-box-basic',
  templateUrl: './combo-box-basic.html'
})
export class ComboBoxBasic {

  // Make sure container can receive focus or else blur events won't be seen.
  @HostBinding('attr.tabindex') tabindex = '0';
  @HostListener('blur', ['$event.target']) onBlur(target) {
    console.log(`onBlur(): ${new Date()} - ${JSON.stringify(target)}`);
  }
}

<div class="btn-group mr-3">
  <input (blur)="onBlur($event.target)" type="text" class="btn btn-outline-success">
  <div class="btn-group" ngbDropdown role="group" aria-label="Button group with nested dropdown">
    <button (blur)="onBlur($event.target)" class="btn btn-outline-primary" ngbDropdownToggle></button>
    <div class="dropdown-menu" ngbDropdownMenu>
      <button class="dropdown-item">One</button>
      <button class="dropdown-item">Two</button>
      <button class="dropdown-item">Four!</button>
    </div>
  </div>
</div>