Question

我有一个Angular Autocomplete组件，尝试在其他事件之后触发ts文件中的（optionSelected）事件。我正在使用this.myControl.setValue(options[1].value)的更新选项设置输入，但这不会触发自动完成（optionSelected）事件。

这是一个堆叠闪电战：

https://stackblitz.com/edit/angular-s3gn1w-xtfxgb?embed=1&file=app/autocomplete-simple-example.ts

import { Component ,ViewChild} from '@angular/core';
import { FormControl } from '@angular/forms';
import { MatAutocompleteTrigger, MatAutocompleteSelectedEvent } from '@angular/material'

/**
 * @title Simple autocomplete
 */
@Component({
  selector: 'autocomplete-simple-example',
  templateUrl: 'autocomplete-simple-example.html',
  styleUrls: ['autocomplete-simple-example.css'],
})
export class AutocompleteSimpleExample {
  @ViewChild(MatAutocompleteTrigger) _auto: MatAutocompleteTrigger;
  myControl = new FormControl();
  activeOption
  options: string[] = ['One', 'Two', 'Three'];
  trigger?: any;

  setValue() {
    let options = this._auto.autocomplete.options.toArray()
    this.myControl.setValue(options[1].value)
  }

  optionSelected($event: MatAutocompleteSelectedEvent): void {
    console.log('event -->', $event);
    this.trigger = $event.option.viewValue;
  }
}

<form class="example-form">
  <mat-form-field class="example-full-width">
    <input type="text" placeholder="Pick one" aria-label="Number" matInput [formControl]="myControl" [matAutocomplete]="auto">
    <mat-autocomplete #auto="matAutocomplete" activeOption="activeOption">
      <mat-option *ngFor="let option of options" [value]="option" (onSelectionChange)="optionSelected($event)">
        {{option}}
      </mat-option>
    </mat-autocomplete>
  </mat-form-field>
</form>

<button (click)="setValue()">Set Value</button>

{{ trigger }}

Answer 1

像这样在mat-autocomplete上使用optionSelected事件：

html

<mat-autocomplete #autoCompleteUser="matAutocomplete" (optionSelected)="onSelectionChanged($event)">

打字稿

onSelectionChanged(event: MatAutocompleteSelectedEvent) {
    console.log(event.option.value);
    [...]
}

从mat-options中删除onSelectionChange事件

Answer 2

您可以使用自动完成实例以编程方式触发更改事件：

    <mat-autocomplete #myAutoComplete="matAutocomplete" 
                      (optionSelected)="onSelectionChanged($event)">

    @ViewChild(MatAutocomplete) myAutocomplete: MatAutocomplete;

    triggerSelectionChanged(): void {
        const ac = this.myAutocomplete; // useless, just for better display here :)
        ac.optionSelected.emit({
                source: ac,
                option: ac.options.toArray().find((o) => o.selected)
        });
    }

如何以编程方式触发optionSelected Angular Material自动完成功能？

2 个答案: