Question

我对编程非常陌生，希望能对SlideToggle数据绑定有任何帮助

我在这里有一个JSFiddle链接：https://jsfiddle.net/haLxj1uy/ （代码也在下方提供）

HTML：

<label class="switch">
    <input type="checkbox" id="togBtn">
    <div class="slider round">
        <span class="on">ON</span>
        <span class="off">OFF</span>
    </div>
</label>

CSS：

.switch {
    position: relative;
    display: inline-block;
    width: 90px;
    height: 34px;
}

.switch input {display:none;}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ca2222;
    -webkit-transition: .4s;
    transition: .4s;
 }

.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: .4s;
  transition: .4s;
}

input:checked + .slider {
  background-color: #2ab934;
}

input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}

input:checked + .slider:before {
  -webkit-transform: translateX(55px);
  -ms-transform: translateX(55px);
  transform: translateX(55px);
}

.on {
  display: none;
}

.on, .off {
  color: white;
  position: absolute;
  transform: translate(-50%,-50%);
  top: 50%;
  left: 50%;
  font-size: 10px;
  font-family: Verdana, sans-serif;
}

input:checked+ .slider .on {
    display: block;
}

input:checked + .slider .off {
    display: none;
}

/* Rounded sliders */
.slider.round {
  border-radius: 34px;
}

.slider.round:before {
  border-radius: 50%;
}

在我的JavaScript中，我做了一个简单的函数：

test(event) { console.log(event.target.value); }

但是，当我滑动切换开/关时，两个console.log都是on（test函数会被触发两次，因为我会使其从“ Off”->开启”和“开启”->“关闭”）。所以我有几个问题：

如何基于变量（条件）动态设置幻灯片？
如何通过JavaScript中的幻灯片切换正确获取true / false（或on / off）？

Answer 1

在角度上，建议的与本地DOM元素实现双向数据绑定的方法是实现ControlValueAccessor接口。通过实现此接口，您的本机DOM元素将与角度形式（模板驱动形式和反应形式）兼容，并且可以与app.UseMvc(routes => { routes.MapRoute( name: "default", template: "{controller=Home}/{action=Index}/{id?}"); });和FormControl指令一起使用。

here is a good article展示了ngModel如何适应更大的前景。

这是滑块的ControlValueAccessor实现；

custom-slide.component.ts

ControlValueAccessor

custom-slide.component.html

import { Component, Renderer2, forwardRef, ViewChild, ElementRef } from '@angular/core';
import { ControlValueAccessor, NG_VALUE_ACCESSOR } from "@angular/forms"

export const CUSTOM_SLIDE_VALUE_ACCESSOR: any = {
  provide: NG_VALUE_ACCESSOR,
  useExisting: forwardRef(() => CustomSlideComponent),
  multi: true,
};

@Component({
  selector: 'my-custom-slide',
  templateUrl: './custom-slide.component.html',
  styleUrls: ['./custom-slide.component.css'],
  providers: [CUSTOM_SLIDE_VALUE_ACCESSOR]
})
export class CustomSlideComponent implements ControlValueAccessor {
  @ViewChild("inp", { static: true }) input: ElementRef<HTMLInputElement>;

  onChange = (_: any) => { };

  onTouched = () => { };

  constructor(private _renderer: Renderer2) { }

  writeValue(value: any): void {
    this._renderer.setProperty(this.input.nativeElement, 'checked', value);
  }

  registerOnChange(fn: (_: any) => {}): void { this.onChange = fn; }

  registerOnTouched(fn: () => {}): void { this.onTouched = fn; }

  setDisabledState(isDisabled: boolean): void {
    this._renderer.setProperty(this.input.nativeElement, 'disabled', isDisabled);
  }
}

custom-slide.component.css（与您提供的CSS相同，未做任何更改。）

<label class="switch">
  <input #inp type="checkbox" id="togBtn" (change)="onChange($event.target.checked)" (blur)="onTouched()">
  <div class="slider round">
    <span class="on">ON</span>
    <span class="off">OFF</span>
  </div>
</label>

您可以在任何地方使用它；

.switch {
  position: relative;
  display: inline-block;
  width: 90px;
  height: 34px;
}

.switch input {display:none;}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ca2222;
  -webkit-transition: .4s;
  transition: .4s;
}

.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: .4s;
  transition: .4s;
}

input:checked + .slider {
  background-color: #2ab934;
}

input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}

input:checked + .slider:before {
  -webkit-transform: translateX(55px);
  -ms-transform: translateX(55px);
  transform: translateX(55px);
}

/*------ ADDED CSS ---------*/
.on
{
  display: none;
}

.on, .off
{
  color: white;
  position: absolute;
  transform: translate(-50%,-50%);
  top: 50%;
  left: 50%;
  font-size: 10px;
  font-family: Verdana, sans-serif;
}

input:checked+ .slider .on
{display: block;}

input:checked + .slider .off
{display: none;}

/*--------- END --------*/

/* Rounded sliders */
.slider.round {
  border-radius: 34px;
}

.slider.round:before {
  border-radius: 50%;}

最后，这是一个有效的演示>>> https://stackblitz.com/edit/angular-w7n6er

如何通过两种方式将数据绑定到Bootstrap中的动态设置幻灯片切换？

1 个答案: