将[(ngModel)]添加到单选按钮组后,默认[已选中]不再有效

Question

我正在研究一个小的可重用组件,它可以设置单选按钮的样式并发出所选的值.

import { Component, OnInit, Input, Output, EventEmitter } from "@angular/core";

@Component({
    moduleId: module.id,
    selector: 'button-select',
    template: `<div class="toggle-group">
                    <div *ngFor="let choice of choices">
                        <input type="radio"
                               id="{{ groupName + choice }}"
                               name="{{groupName}}"
                               value="{{ choice }}"
                               [checked]="choice === defaultChoice"
                               [(ngModel)]="value"
                               (ngModelChange)="choose($event)" />
                        <label class="toggle-button"
                               for="{{ groupName + choice }}">{{ choice }}</label>
                    </div>
                </div>`,
    styleUrls: [
        'editableField.css',
        'buttonSelect.css'
    ]
})

export class ButtonSelectComponent implements OnInit {
    @Input() choices: string[];
    @Input() defaultChoice: string;
    @Input() groupName: string;
    @Input() value: string;

    @Output() valueChosen: EventEmitter<any> = new EventEmitter();

    ngOnInit() {
        this.choose(this.defaultChoice);
    }

    private choose(value: string) {
        this.valueChosen.emit(value);
    }
}

该组件实现如下:

<button-select #statusFilter
               [choices]="['All', 'Active', 'Draft']"
               [defaultChoice]="'All'"
               [groupName]="'statusFilter'"
               (valueChosen)="filterChosen('statusFilter', $event)"
</button-select>

在添加[(ngModel)]="value" (ngModelChange)="choose($event)"按钮选择Component之前,该[checked]="choice === defaultChoice"指令正确地设置checked了相关的属性<input />.

添加之后[(ngModel)],只会 ng-reflect-checked="true"设置,这会阻止视觉样式显示默认值(因为我的CSS使用伪选择器).

更改[(ngModel)]为[ngModel]无影响.

为什么会发生这种情况,我该如何解决？

Answer 1

我想,你不需要这个[checked]="choice === defaultChoice".试试这个 :

<input type="radio"
       id="{{ groupName + choice }}"
       name="{{groupName}}"
       [value]="choice"
       [(ngModel)]="defaultChoice"
       (ngModelChange)="choose($event)" />

当[value] = [(ngModel)]选择了无线电.