refactor(checkbox): use native input type=checkbox

packages/core/src/components.d.ts

@@ -594,6 +594,7 @@ declare global {
       
         color?: string,
         mode?: 'ios' | 'md',
+        name?: string,
         checked?: boolean,
         disabled?: boolean,
         value?: string

packages/core/src/components/checkbox/checkbox.ios.scss

@@ -123,6 +123,27 @@ $checkbox-ios-item-end-margin-start:      0 !default;
 }
 
 
+// iOS Checkbox Keyboard Focus
+// -----------------------------------------
+
+.checkbox-key .checkbox-icon::after {
+  position: absolute;
+  top: -9px;
+  left: -9px;
+
+  display: block;
+
+  width: 36px;
+  height: 36px;
+
+  background: #86A8DF;
+  opacity: .3;
+
+  border-radius: 50%;
+  content: '';
+}
+
+
 // iOS Checkbox Within An Item
 // -----------------------------------------
 

packages/core/src/components/checkbox/checkbox.md.scss

@@ -142,6 +142,27 @@ $checkbox-md-item-end-margin-start:      0 !default;
 }
 
 
+// Material Design Checkbox Keyboard Focus
+// -----------------------------------------
+
+.checkbox-key .checkbox-icon::after {
+  position: absolute;
+  top: -12px;
+  left: -12px;
+
+  display: block;
+
+  width: 36px;
+  height: 36px;
+
+  background: #86A8DF;
+  opacity: .3;
+
+  border-radius: 50%;
+  content: '';
+}
+
+
 // Material Design Checkbox Within An Item
 // -----------------------------------------
 

packages/core/src/components/checkbox/checkbox.scss

@@ -9,7 +9,7 @@ ion-checkbox {
   display: inline-block;
 }
 
-.checkbox-cover {
+ion-checkbox input {
   @include position(0, null, null, 0);
 
   position: absolute;
@@ -19,4 +19,8 @@ ion-checkbox {
 
   background: transparent;
   cursor: pointer;
+
+  -webkit-appearance: none;
+  -moz-appearance: none;
+  appearance: none;
 }

packages/core/src/components/checkbox/checkbox.tsx

@@ -1,5 +1,5 @@
 import { BlurEvent, CheckboxInput, CheckedInputChangeEvent, FocusEvent, StyleEvent } from '../../utils/input-interfaces';
-import { Component, CssClassMap, Event, EventEmitter, Listen, Prop, PropDidChange } from '@stencil/core';
+import { Component, CssClassMap, Event, EventEmitter, Prop, PropDidChange, State } from '@stencil/core';
 
 
 @Component({
@@ -13,10 +13,46 @@ import { Component, CssClassMap, Event, EventEmitter, Listen, Prop, PropDidChang
   }
 })
 export class Checkbox implements CheckboxInput {
-  private checkboxId: string;
-  private labelId: string;
+  private didLoad: boolean;
+  private inputId: string;
+  private nativeInput: HTMLInputElement;
   private styleTmr: any;
 
+  @State() keyFocus: boolean;
+
+  /**
+   * @input {string} The color to use from your Sass `$colors` map.
+   * Default options are: `"primary"`, `"secondary"`, `"danger"`, `"light"`, and `"dark"`.
+   * For more information, see [Theming your App](/docs/theming/theming-your-app).
+   */
+  @Prop() color: string;
+
+  /**
+   * @input {string} The mode determines which platform styles to use.
+   * Possible values are: `"ios"` or `"md"`.
+   * For more information, see [Platform Styles](/docs/theming/platform-specific-styles).
+   */
+  @Prop() mode: 'ios' | 'md';
+
+  /**
+   */
+  @Prop() name: string;
+
+  /**
+   * @input {boolean} If true, the checkbox is selected. Defaults to `false`.
+   */
+  @Prop({ mutable: true }) checked = false;
+
+  /*
+   * @input {boolean} If true, the user cannot interact with the checkbox. Default false.
+   */
+  @Prop() disabled = false;
+
+  /**
+   * @input {string} the value of the checkbox.
+   */
+  @Prop({ mutable: true }) value: string;
+
   /**
    * @output {Event} Emitted when the checked property has changed.
    */
@@ -37,55 +73,51 @@ export class Checkbox implements CheckboxInput {
    */
   @Event() ionStyle: EventEmitter<StyleEvent>;
 
-  /**
-   * @input {string} The color to use from your Sass `$colors` map.
-   * Default options are: `"primary"`, `"secondary"`, `"danger"`, `"light"`, and `"dark"`.
-   * For more information, see [Theming your App](/docs/theming/theming-your-app).
-   */
-  @Prop() color: string;
-
-  /**
-   * @input {string} The mode determines which platform styles to use.
-   * Possible values are: `"ios"` or `"md"`.
-   * For more information, see [Platform Styles](/docs/theming/platform-specific-styles).
-   */
-  @Prop() mode: 'ios' | 'md';
-
-  /**
-   * @input {boolean} If true, the checkbox is selected. Defaults to `false`.
-   */
-  @Prop({ mutable: true }) checked: boolean = false;
-
-  /*
-   * @input {boolean} If true, the user cannot interact with the checkbox. Default false.
-   */
-  @Prop() disabled: boolean = false;
-
-  /**
-   * @input {string} the value of the checkbox.
-   */
-  @Prop({ mutable: true }) value: string;
-
 
   componentWillLoad() {
+    this.inputId = 'ion-cb-' + (checkboxIds++);
+    if (this.value === undefined) {
+      this.value = this.inputId;
+    }
     this.emitStyle();
   }
 
+  componentDidLoad() {
+    this.nativeInput.checked = this.checked;
+    this.didLoad = true;
+
+    const parentItem = this.nativeInput.closest('ion-item');
+    if (parentItem) {
+      const itemLabel = parentItem.querySelector('ion-label');
+      if (itemLabel) {
+        itemLabel.id = this.inputId + '-lbl';
+        this.nativeInput.setAttribute('aria-labelledby', itemLabel.id);
+      }
+    }
+  }
+
   @PropDidChange('checked')
   checkedChanged(isChecked: boolean) {
-    this.ionChange.emit({
-      checked: isChecked,
-      value: this.value
-    });
+    if (this.nativeInput.checked !== isChecked) {
+      // keep the checked value and native input `nync
+      this.nativeInput.checked = isChecked;
+    }
+    if (this.didLoad) {
+      this.ionChange.emit({
+        checked: isChecked,
+        value: this.value
+      });
+    }
     this.emitStyle();
   }
 
   @PropDidChange('disabled')
-  disabledChanged() {
+  disabledChanged(isDisabled: boolean) {
+    this.nativeInput.disabled = isDisabled;
     this.emitStyle();
   }
 
-  private emitStyle() {
+  emitStyle() {
     clearTimeout(this.styleTmr);
 
     this.styleTmr = setTimeout(() => {
@@ -96,22 +128,29 @@ export class Checkbox implements CheckboxInput {
     });
   }
 
-  @Listen('keydown.space')
-  onSpace(ev: KeyboardEvent) {
-    this.toggle();
-    ev.stopPropagation();
-    ev.preventDefault();
+  onChange() {
+    this.checked = !this.checked;
   }
 
-  toggle() {
-    this.checked = !this.checked;
+  onKeyUp() {
+    this.keyFocus = true;
+  }
+
+  onFocus() {
+    this.ionFocus.emit();
+  }
+
+  onBlur() {
+    this.keyFocus = false;
+    this.ionBlur.emit();
   }
 
   hostData() {
     return {
       class: {
         'checkbox-checked': this.checked,
-        'checkbox-disabled': this.disabled
+        'checkbox-disabled': this.disabled,
+        'checkbox-key': this.keyFocus
       }
     };
   }
@@ -126,16 +165,19 @@ export class Checkbox implements CheckboxInput {
       <div class={checkboxClasses}>
         <div class='checkbox-inner'></div>
       </div>,
-      <button
-        class='checkbox-cover'
-        onClick={() => this.toggle()}
-        id={this.checkboxId}
-        aria-checked={this.checked ? 'true' : false}
-        aria-disabled={this.disabled ? 'true' : false}
-        aria-labelledby={this.labelId}
-        role='checkbox'
-        tabIndex={0}
-      />
+      <input
+        type='checkbox'
+        onChange={this.onChange.bind(this)}
+        onFocus={this.onFocus.bind(this)}
+        onBlur={this.onBlur.bind(this)}
+        onKeyUp={this.onKeyUp.bind(this)}
+        id={this.inputId}
+        name={this.name}
+        value={this.value}
+        disabled={this.disabled}
+        ref={r => this.nativeInput = (r as any)}/>
     ];
   }
 }
+
+let checkboxIds = 0;

packages/core/src/components/checkbox/readme.md

@@ -10,50 +10,22 @@ Placed in an `ion-item` or used as a stand-alone checkbox.
 
    <ion-item>
      <ion-label>Pepperoni</ion-label>
-     <ion-checkbox [(ngModel)]="pepperoni"></ion-checkbox>
+     <ion-checkbox value="pepperoni" checked></ion-checkbox>
    </ion-item>
 
    <ion-item>
      <ion-label>Sausage</ion-label>
-     <ion-checkbox [(ngModel)]="sausage" disabled="true"></ion-checkbox>
+     <ion-checkbox value="sausage" disabled></ion-checkbox>
    </ion-item>
 
    <ion-item>
      <ion-label>Mushrooms</ion-label>
-     <ion-checkbox [(ngModel)]="mushrooms"></ion-checkbox>
+     <ion-checkbox value="mushrooms"></ion-checkbox>
    </ion-item>
 
  </ion-list>
 ```
 
-@advanced
-
-```html
-
-<!-- Call function when state changes -->
- <ion-list>
-
-   <ion-item>
-     <ion-label>Cucumber</ion-label>
-     <ion-checkbox [(ngModel)]="cucumber" (ionChange)="updateCucumber()"></ion-checkbox>
-   </ion-item>
-
- </ion-list>
-```
-
-```ts
-@Component({
-  templateUrl: 'main.html'
-})
-class SaladPage {
-  cucumber: boolean;
-
-  updateCucumber() {
-    console.log('Cucumbers new state:' + this.cucumber);
-  }
-}
-```
-
 
 <!-- Auto Generated Below -->
 

packages/core/src/components/checkbox/test/basic/index.html

@@ -40,6 +40,10 @@
           <ion-label>Dark</ion-label>
           <ion-checkbox color="dark" checked></ion-checkbox>
         </ion-item>
+        <ion-item>
+          <ion-label>Unchecked by Default</ion-label>
+          <ion-checkbox></ion-checkbox>
+        </ion-item>
         <ion-item>
           <ion-label>Disabled</ion-label>
           <ion-checkbox disabled></ion-checkbox>