Angular FormGroup 不会在 patchValue 或 setValue 之后立即更新它的值 [英] Angular FormGroup won't update it's value immediately after patchValue or setValue

问题描述

我有一个像下面这样的表格:

 createForm() {this.procedimentoForm = this.formBuilder.group({名称: ['', Validators.required],描述: ['', Validators.required],conteudo: ['', Validators.required],solucao: ['', Validators.required],台面:[''，Validators.required]});}

模板:

{{procedimentoForm.value.conteudo}}<div class="field"><label>描述</label><input type="text" placeholder="Decrição" formControlName="descricao">

<div class="field"><label>Conteúdo</label><tinymce [elementId]="'conteudo'" (onEditorKeyup)="keyupHandlerFunction($event)"></tinymce>

</表单>

它使用实现 TinyMCE 编辑器的自定义组件:

import { Component, AfterViewInit, ViewChild, EventEmitter, forwardRef, ElementRef, OnDestroy, Input, Output } from '@angular/core';进口 {控制值访问器，NG_VALUE_ACCESSOR，NG_VALIDATORS，表单控件，验证器来自'@angular/forms';@成分({选择器:'tinymce'，templateUrl: './tinymce.component.html',})导出类 TinyMCEComponent 实现 AfterViewInit、OnDestroy {@Input() elementId: 字符串；@Output() onEditorKeyup = new EventEmitter();编辑;ngAfterViewInit() {tinymce.init({选择器:'#' + this.elementId，插件:['链接'，'粘贴'，'表格']，skin_url: '../assets/skins/lightgray',设置:编辑器 =>{this.editor = 编辑器；editor.on('keyup', () => {const content = editor.getContent();this.onEditorKeyup.emit(content);});}});}ngOnDestroy() {tinymce.remove(this.editor);}

}

表单中的 keyup 处理程序如下所示:

keyupHandlerFunction(event) {console.log(this.procedimentoForm);this.procedimentoForm.markAsDirty()this.procedimentoForm.patchValue({ conteudo: event }, {onlySelf: false, emitEvent: true});console.log(this.procedimentoForm.value.conteudo);}

问题是，我可以看到 this.procedimentoForm.value.conteudo 正在发生变化，因为我在 keyup 事件处理程序中记录了console.log(this.procedimentoForm.value.conteudo)".但是，{{procedimentoForm.value.conteudo}} 在我将焦点移出编辑器之前不会更新.此外，在焦点更改之前，验证不会更新.我不明白为什么.

解决方案

如果支持值正在更新，但更改未反映在视图中，则很可能尚未将其标记为更新.

您可以使用 ChangeDetectorRef 手动检测更改:https://angular.io/api/core/ChangeDetectorRef#!#detectChanges-锚

I have a form like below:

 createForm() {
    this.procedimentoForm = this.formBuilder.group({
      nome: ['', Validators.required],
      descricao: ['', Validators.required],
      conteudo: ['', Validators.required],
      solucao: ['', Validators.required],
      mesa: ['', Validators.required]
    });
  }

The template:

<form [formGroup]="procedimentoForm" class="ui form">
  {{procedimentoForm.value.conteudo}}


  <div class="field">
    <label>Descrição</label>
    <input type="text" placeholder="Descrição" formControlName="descricao">
  </div>

  <div class="field">
    <label>Conteúdo</label>
    <tinymce [elementId]="'conteudo'" (onEditorKeyup)="keyupHandlerFunction($event)"></tinymce>
  </div>

</form>

It uses a custom component that implement a TinyMCE editor:

import { Component, AfterViewInit, ViewChild, EventEmitter, forwardRef, ElementRef, OnDestroy, Input, Output } from '@angular/core';
import { 
ControlValueAccessor, 
NG_VALUE_ACCESSOR, 
NG_VALIDATORS, 
FormControl, 
Validator 
} from '@angular/forms';

@Component({
selector: 'tinymce',
templateUrl: './tinymce.component.html',
})
export class TinyMCEComponent implements AfterViewInit, OnDestroy {
@Input() elementId: String;
@Output() onEditorKeyup = new EventEmitter();

editor;

ngAfterViewInit() {
    tinymce.init({
        selector: '#' + this.elementId,
        plugins: ['link', 'paste', 'table'],
        skin_url: '../assets/skins/lightgray',
        setup: editor => {
            this.editor = editor;
            editor.on('keyup', () => {
                const content = editor.getContent();
                this.onEditorKeyup.emit(content);
            });
        }
    });
}

ngOnDestroy() {
    tinymce.remove(this.editor);
}

}

The keyup handler in the form looks like this:

keyupHandlerFunction(event) {
    console.log(this.procedimentoForm);
    this.procedimentoForm.markAsDirty()
    this.procedimentoForm.patchValue({ conteudo: event }, {onlySelf: false, emitEvent: true});
    console.log(this.procedimentoForm.value.conteudo);
  }

The problem is, I can see that this.procedimentoForm.value.conteudo is changing because I log "console.log(this.procedimentoForm.value.conteudo)" in the keyup event handler. But, {{procedimentoForm.value.conteudo}} doesn't update until I change the focus out of the editor. Also, the validation won't update until the focus changes. I can't see why.

解决方案

If the backing value is updating, but the changes aren't being reflected in the view, then it's likely that it hasn't been marked for update.

You can use the ChangeDetectorRef to manually detect changes: https://angular.io/api/core/ChangeDetectorRef#!#detectChanges-anchor

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