How to use [(ngModel)] on div's contenteditable in angular2?
NgModel
expects the bound element to have a value
property, which div
s don't have. That's why you get the No value accessor
error.
You can set up your own equivalent property and event databinding using the textContent
property (instead of value
) and the input
event:
import {Component} from 'angular2/core';
@Component({
selector: 'my-app',
template: `{{title}}
<div contenteditable="true"
[textContent]="model" (input)="model=$event.target.textContent"></div>
<p>{{model}}`
})
export class AppComponent {
title = 'Angular 2 RC.4';
model = 'some text';
constructor() { console.clear(); }
}
Plunker
I don't know if the input
event is supported on all browsers for contenteditable
. You could always bind to some keyboard event instead.
Updated answer (2017-10-09):
Now I have ng-contenteditable module. Its compatibility with Angular forms.
Old answer (2017-05-11): In my case, I can simple to do:
<div
contenteditable="true"
(input)="post.postTitle = $event.target.innerText"
>{{ postTitle }}</div>
Where post
- it's object with property postTitle
.
First time, after ngOnInit()
and get post
from backend, I set this.postTitle = post.postTitle
in my component.
Working Plunkr here http://plnkr.co/edit/j9fDFc, but relevant code below.
Binding to and manually updating textContent
wasn't working for me, it doesn't handle line breaks (in Chrome, typing after a line break jumps cursor back to the beginning) but I was able to get it work using a contenteditable model directive from https://www.namekdev.net/2016/01/two-way-binding-to-contenteditable-element-in-angular-2/.
I tweaked it to handle multi-line plain text (with \n
s, not <br>
s) by using white-space: pre-wrap
, and updated it to use keyup
instead of blur
. Note that some solutions to this problem use the input
event which isn't supported on IE or Edge on contenteditable
elements yet.
Here's the code:
Directive:
import {Directive, ElementRef, Input, Output, EventEmitter, SimpleChanges} from 'angular2/core';
@Directive({
selector: '[contenteditableModel]',
host: {
'(keyup)': 'onKeyup()'
}
})
export class ContenteditableModel {
@Input('contenteditableModel') model: string;
@Output('contenteditableModelChange') update = new EventEmitter();
/**
* By updating this property on keyup, and checking against it during
* ngOnChanges, we can rule out change events fired by our own onKeyup.
* Ideally we would not have to check against the whole string on every
* change, could possibly store a flag during onKeyup and test against that
* flag in ngOnChanges, but implementation details of Angular change detection
* cycle might make this not work in some edge cases?
*/
private lastViewModel: string;
constructor(private elRef: ElementRef) {
}
ngOnChanges(changes: SimpleChanges) {
if (changes['model'] && changes['model'].currentValue !== this.lastViewModel) {
this.lastViewModel = this.model;
this.refreshView();
}
}
/** This should probably be debounced. */
onKeyup() {
var value = this.elRef.nativeElement.innerText;
this.lastViewModel = value;
this.update.emit(value);
}
private refreshView() {
this.elRef.nativeElement.innerText = this.model
}
}
Usage:
import {Component} from 'angular2/core'
import {ContenteditableModel} from './contenteditable-model'
@Component({
selector: 'my-app',
providers: [],
directives: [ContenteditableModel],
styles: [
`div {
white-space: pre-wrap;
/* just for looks: */
border: 1px solid coral;
width: 200px;
min-height: 100px;
margin-bottom: 20px;
}`
],
template: `
<b>contenteditable:</b>
<div contenteditable="true" [(contenteditableModel)]="text"></div>
<b>Output:</b>
<div>{{text}}</div>
<b>Input:</b><br>
<button (click)="text='Success!'">Set model to "Success!"</button>
`
})
export class App {
text: string;
constructor() {
this.text = "This works\nwith multiple\n\nlines"
}
}
Only tested in Chrome and FF on Linux so far.