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/**
* @demo demo/index.html
* @polymerBehavior
*/
Polymer.IronButtonStateImpl = {
properties: {
/**
* If true, the user is currently holding down the button.
*/
pressed: {
type: Boolean,
readOnly: true,
value: false,
reflectToAttribute: true,
observer: '_pressedChanged'
},
/**
* If true, the button toggles the active state with each tap or press
* of the spacebar.
*/
toggles: {
type: Boolean,
value: false,
reflectToAttribute: true
},
/**
* If true, the button is a toggle and is currently in the active state.
*/
active: {
type: Boolean,
value: false,
notify: true,
reflectToAttribute: true,
observer: '_activeChanged'
},
/**
* True if the element is currently being pressed by a "pointer," which
* is loosely defined as mouse or touch input (but specifically excluding
* keyboard input).
*/
pointerDown: {
type: Boolean,
readOnly: true,
value: false
},
/**
* True if the input device that caused the element to receive focus
* was a keyboard.
*/
receivedFocusFromKeyboard: {
type: Boolean,
readOnly: true
}
},
listeners: {
down: '_downHandler',
up: '_upHandler',
tap: '_tapHandler'
},
observers: [
'_detectKeyboardFocus(focused)'
],
keyBindings: {
'enter:keydown': '_asyncClick',
'space:keydown': '_spaceKeyDownHandler',
'space:keyup': '_spaceKeyUpHandler',
},
_tapHandler: function() {
if (this.toggles) {
// a tap is needed to toggle the active state
this._userActivate(!this.active);
} else {
this.active = false;
}
},
_detectKeyboardFocus: function(focused) {
this._setReceivedFocusFromKeyboard(!this.pointerDown && focused);
},
// to emulate native checkbox, (de-)activations from a user interaction fire
// 'change' events
_userActivate: function(active) {
this.active = active;
this.fire('change');
},
_downHandler: function() {
this._setPointerDown(true);
this._setPressed(true);
this._setReceivedFocusFromKeyboard(false);
},
_upHandler: function() {
this._setPointerDown(false);
this._setPressed(false);
},
_spaceKeyDownHandler: function(event) {
var keyboardEvent = event.detail.keyboardEvent;
keyboardEvent.preventDefault();
keyboardEvent.stopImmediatePropagation();
this._setPressed(true);
},
_spaceKeyUpHandler: function() {
if (this.pressed) {
this._asyncClick();
}
this._setPressed(false);
},
// trigger click asynchronously, the asynchrony is useful to allow one
// event handler to unwind before triggering another event
_asyncClick: function() {
this.async(function() {
this.click();
}, 1);
},
// any of these changes are considered a change to button state
_pressedChanged: function(pressed) {
this._changedButtonState();
},
_activeChanged: function(active) {
if (this.toggles) {
this.setAttribute('aria-pressed', active ? 'true' : 'false');
} else {
this.removeAttribute('aria-pressed');
}
this._changedButtonState();
},
_controlStateChanged: function() {
if (this.disabled) {
this._setPressed(false);
} else {
this._changedButtonState();
}
},
// provide hook for follow-on behaviors to react to button-state
_changedButtonState: function() {
if (this._buttonStateChanged) {
this._buttonStateChanged(); // abstract
}
}
};
/** @polymerBehavior Polymer.IronButtonState */
Polymer.IronButtonState = [
Polymer.IronA11yKeysBehavior,
Polymer.IronButtonStateImpl
];
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