使用指令 Angular 2 更改输入的 ngModel 值 [英] Change an input's ngModel value using a directive Angular 2
问题描述
我被困在如何使用指令访问和更改输入 ngModel
值.问题的结果是,当我选择所需的地址时,模型的地址值不会更新……它只是设置为我在输入中实际键入的内容,而不是输入的最终值.
I'm stuck on how to access and change an inputs ngModel
value using a directive. The outcome of the issue is that the model's address value doesn't update when I select the desired address...it's just set to what I actually typed into the input, rather than final value of the input.
我输入830":
我选择8300 Fauntleroy Way Southwest, Seattle, WA, United States":
结果值:
{
address: '830'
}
期望值:
{
address: '8300 Fauntleroy Way Southwest, Seattle, WA, United States'
}
在 AngularJS 中,我可以这样做:
In AngularJS I could do this:
(function() {
'use strict';
angular
.module('casemanagerApp')
.directive('googleplace', googleplace);
function googleplace() {
var directive = {
require: 'ngModel',
link: link
};
return directive;
function link(scope, element, attrs, model) {
var options = {
types: [],
componentRestrictions: {}
};
scope.gPlace = new google.maps.places.Autocomplete(element[0], options); // jshint ignore:line
google.maps.event.addListener(scope.gPlace, 'place_changed', function() { // jshint ignore:line
scope.$apply(function() {
model.$setViewValue(element.val());
});
});
}
}
})();
但是现在我正在尝试将其转换为 Angular 2,我有点卡住了.到目前为止,这是我对转换的了解:
But now that I'm trying to convert it Angular 2, I'm a little stuck. Here's what I have so far on the conversion:
/// <reference path="../../../../typings/browser/ambient/googlemaps/index.d.ts"/>
import { Directive, ElementRef, OnInit } from '@angular/core';
@Directive({
selector: '[google-places]'
})
export class GooglePlaces implements OnInit {
constructor(private _el: ElementRef) { }
ngOnInit() {
let gPlace = new google.maps.places.Autocomplete(this._el.nativeElement);
google.maps.event.addListener(gPlace, 'place_changed', () => console.log(this._el.nativeElement));
}
}
用法:
<input type="text"
ngControl="address"
placeholder="Enter a location"
[(ngModel)]="subject.address"
#address="ngForm"
google-places
required>
问题的核心是我不明白如何在 Angular 2 中执行 model.$setViewValue(element.val());
的等效操作.
The heart of the issue is I don't understand how to do the equivalent of model.$setViewValue(element.val());
in Angular 2.
如有任何帮助,我们将不胜感激.
Any assistance would be greatly appreciated.
推荐答案
我最终得到了这个,虽然我不明白为什么它会起作用,因为我没有将 ngModelChange
绑定到元素...但它有效.
I ended up getting this to work, although I don't understand why it works because I'm not binding ngModelChange
to the element...but it works.
指令:
/// <reference path="../../../../typings/browser/ambient/googlemaps/index.d.ts"/>
import { Directive, ElementRef, Output, EventEmitter, OnInit, NgZone } from '@angular/core';
@Directive({
selector: '[google-places]'
})
export class GooglePlaces implements OnInit {
@Output() ngModelChange: EventEmitter<any> = new EventEmitter(false);
options = {
types: ['address'],
componentRestrictions: { country: "us" }
};
constructor(
private _el: ElementRef,
private _ngZone: NgZone) { }
ngOnInit() {
let gPlace = new google.maps.places.Autocomplete(this._el.nativeElement, this.options);
google.maps.event.addListener(gPlace, 'place_changed', () => {
this._ngZone.run(() =>
this.ngModelChange.emit(this._el.nativeElement.value));
});
}
}
组件模板:
<input type="text"
class="form-control"
ngControl="address"
id="subjectAddress"
placeholder="Enter a location"
[(ngModel)]="subject.address"
#address="ngForm"
google-places
required>
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