1<!--
2Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
3This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
4The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
5The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
6Code distributed by Google as part of the polymer project is also
7subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
8-->
9
10<!--
11`paper-toggle-button` provides a ON/OFF switch that user can toggle the state
12by tapping or by dragging the swtich.
13
14Example:
15
16    <paper-toggle-button></paper-toggle-button>
17
18Styling toggle button:
19
20To change the ink color for checked state:
21
22    paper-toggle-button::shadow paper-radio-button::shadow #ink[checked] {
23      color: #4285f4;
24    }
25    
26To change the radio checked color:
27    
28    paper-toggle-button::shadow paper-radio-button::shadow #onRadio {
29      background-color: #4285f4;
30    }
31    
32To change the bar color for checked state:
33
34    paper-toggle-button::shadow #toggleBar[checked] {
35      background-color: #4285f4;
36    }
37    
38To change the ink color for unchecked state:
39
40    paper-toggle-button::shadow paper-radio-button::shadow #ink {
41      color: #b5b5b5;
42    }
43    
44To change the radio unchecked color:
45    
46    paper-toggle-button::shadow paper-radio-button::shadow #offRadio {
47      border-color: #b5b5b5;
48    }
49
50To change the bar color for unchecked state:
51
52    paper-toggle-button::shadow #toggleBar {
53      background-color: red;
54    }
55
56@group Paper Elements
57@element paper-toggle-button
58@homepage github.io
59-->
60
61<link rel="import" href="/paper-radio-button/paper-radio-button.html">
62
63<polymer-element name="paper-toggle-button" attributes="checked" role="button" aria-pressed="false" tabindex="0">
64<template>
65
66  <link rel="stylesheet" href="paper-toggle-button.css">
67
68  <div id="toggleContainer">
69  
70    <div id="toggleBar" checked?="{{checked}}"></div>
71  
72    <paper-radio-button id="toggleRadio" toggles checked="{{checked}}"
73        on-trackstart="{{trackStart}}" on-trackx="{{trackx}}" on-trackend="{{trackEnd}}"></paper-radio-button>
74    
75  </div>
76
77</template>
78<script>
79
80  Polymer('paper-toggle-button', {
81    
82    /**
83     * Fired when the checked state changes.
84     *
85     * @event change
86     */
87
88    /**
89     * Gets or sets the state, `true` is checked and `false` is unchecked.
90     *
91     * @attribute checked
92     * @type boolean
93     * @default false
94     */
95    checked: false,
96
97    trackStart: function(e) {
98      this._w = this.$.toggleBar.offsetLeft + this.$.toggleBar.offsetWidth;
99      e.preventTap();
100    },
101
102    trackx: function(e) {
103      this._x = Math.min(this._w, 
104          Math.max(0, this.checked ? this._w + e.dx : e.dx));
105      this.$.toggleRadio.classList.add('dragging');
106      var s =  this.$.toggleRadio.style;
107      s.webkitTransform = s.transform = 'translate3d(' + this._x + 'px,0,0)';
108    },
109
110    trackEnd: function() {
111      var s =  this.$.toggleRadio.style;
112      s.webkitTransform = s.transform = null;
113      this.$.toggleRadio.classList.remove('dragging');
114      this.checked = Math.abs(this._x) > this._w / 2;
115    },
116
117    checkedChanged: function() {
118      this.setAttribute('aria-pressed', Boolean(this.checked));
119      this.fire('change');
120    }
121
122  });
123
124</script>
125</polymer-element>
126