d2-ui
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JavaScript
/**
* Copyright 2013-2015, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule ReactBrowserEventEmitter
* @typechecks static-only
*/
;
var EventConstants = require('./EventConstants');
var EventPluginHub = require('./EventPluginHub');
var EventPluginRegistry = require('./EventPluginRegistry');
var ReactEventEmitterMixin = require('./ReactEventEmitterMixin');
var ReactPerf = require('./ReactPerf');
var ViewportMetrics = require('./ViewportMetrics');
var assign = require('./Object.assign');
var isEventSupported = require('./isEventSupported');
/**
* Summary of `ReactBrowserEventEmitter` event handling:
*
* - Top-level delegation is used to trap most native browser events. This
* may only occur in the main thread and is the responsibility of
* ReactEventListener, which is injected and can therefore support pluggable
* event sources. This is the only work that occurs in the main thread.
*
* - We normalize and de-duplicate events to account for browser quirks. This
* may be done in the worker thread.
*
* - Forward these native events (with the associated top-level type used to
* trap it) to `EventPluginHub`, which in turn will ask plugins if they want
* to extract any synthetic events.
*
* - The `EventPluginHub` will then process each event by annotating them with
* "dispatches", a sequence of listeners and IDs that care about that event.
*
* - The `EventPluginHub` then dispatches the events.
*
* Overview of React and the event system:
*
* +------------+ .
* | DOM | .
* +------------+ .
* | .
* v .
* +------------+ .
* | ReactEvent | .
* | Listener | .
* +------------+ . +-----------+
* | . +--------+|SimpleEvent|
* | . | |Plugin |
* +-----|------+ . v +-----------+
* | | | . +--------------+ +------------+
* | +-----------.--->|EventPluginHub| | Event |
* | | . | | +-----------+ | Propagators|
* | ReactEvent | . | | |TapEvent | |------------|
* | Emitter | . | |<---+|Plugin | |other plugin|
* | | . | | +-----------+ | utilities |
* | +-----------.--->| | +------------+
* | | | . +--------------+
* +-----|------+ . ^ +-----------+
* | . | |Enter/Leave|
* + . +-------+|Plugin |
* +-------------+ . +-----------+
* | application | .
* |-------------| .
* | | .
* | | .
* +-------------+ .
* .
* React Core . General Purpose Event Plugin System
*/
var alreadyListeningTo = {};
var isMonitoringScrollValue = false;
var reactTopListenersCounter = 0;
// For events like 'submit' which don't consistently bubble (which we trap at a
// lower node than `document`), binding at `document` would cause duplicate
// events so we don't include them here
var topEventMapping = {
topAbort: 'abort',
topBlur: 'blur',
topCanPlay: 'canplay',
topCanPlayThrough: 'canplaythrough',
topChange: 'change',
topClick: 'click',
topCompositionEnd: 'compositionend',
topCompositionStart: 'compositionstart',
topCompositionUpdate: 'compositionupdate',
topContextMenu: 'contextmenu',
topCopy: 'copy',
topCut: 'cut',
topDoubleClick: 'dblclick',
topDrag: 'drag',
topDragEnd: 'dragend',
topDragEnter: 'dragenter',
topDragExit: 'dragexit',
topDragLeave: 'dragleave',
topDragOver: 'dragover',
topDragStart: 'dragstart',
topDrop: 'drop',
topDurationChange: 'durationchange',
topEmptied: 'emptied',
topEncrypted: 'encrypted',
topEnded: 'ended',
topError: 'error',
topFocus: 'focus',
topInput: 'input',
topKeyDown: 'keydown',
topKeyPress: 'keypress',
topKeyUp: 'keyup',
topLoadedData: 'loadeddata',
topLoadedMetadata: 'loadedmetadata',
topLoadStart: 'loadstart',
topMouseDown: 'mousedown',
topMouseMove: 'mousemove',
topMouseOut: 'mouseout',
topMouseOver: 'mouseover',
topMouseUp: 'mouseup',
topPaste: 'paste',
topPause: 'pause',
topPlay: 'play',
topPlaying: 'playing',
topProgress: 'progress',
topRateChange: 'ratechange',
topScroll: 'scroll',
topSeeked: 'seeked',
topSeeking: 'seeking',
topSelectionChange: 'selectionchange',
topStalled: 'stalled',
topSuspend: 'suspend',
topTextInput: 'textInput',
topTimeUpdate: 'timeupdate',
topTouchCancel: 'touchcancel',
topTouchEnd: 'touchend',
topTouchMove: 'touchmove',
topTouchStart: 'touchstart',
topVolumeChange: 'volumechange',
topWaiting: 'waiting',
topWheel: 'wheel'
};
/**
* To ensure no conflicts with other potential React instances on the page
*/
var topListenersIDKey = '_reactListenersID' + String(Math.random()).slice(2);
function getListeningForDocument(mountAt) {
// In IE8, `mountAt` is a host object and doesn't have `hasOwnProperty`
// directly.
if (!Object.prototype.hasOwnProperty.call(mountAt, topListenersIDKey)) {
mountAt[topListenersIDKey] = reactTopListenersCounter++;
alreadyListeningTo[mountAt[topListenersIDKey]] = {};
}
return alreadyListeningTo[mountAt[topListenersIDKey]];
}
/**
* `ReactBrowserEventEmitter` is used to attach top-level event listeners. For
* example:
*
* ReactBrowserEventEmitter.putListener('myID', 'onClick', myFunction);
*
* This would allocate a "registration" of `('onClick', myFunction)` on 'myID'.
*
* @internal
*/
var ReactBrowserEventEmitter = assign({}, ReactEventEmitterMixin, {
/**
* Injectable event backend
*/
ReactEventListener: null,
injection: {
/**
* @param {object} ReactEventListener
*/
injectReactEventListener: function (ReactEventListener) {
ReactEventListener.setHandleTopLevel(ReactBrowserEventEmitter.handleTopLevel);
ReactBrowserEventEmitter.ReactEventListener = ReactEventListener;
}
},
/**
* Sets whether or not any created callbacks should be enabled.
*
* @param {boolean} enabled True if callbacks should be enabled.
*/
setEnabled: function (enabled) {
if (ReactBrowserEventEmitter.ReactEventListener) {
ReactBrowserEventEmitter.ReactEventListener.setEnabled(enabled);
}
},
/**
* @return {boolean} True if callbacks are enabled.
*/
isEnabled: function () {
return !!(ReactBrowserEventEmitter.ReactEventListener && ReactBrowserEventEmitter.ReactEventListener.isEnabled());
},
/**
* We listen for bubbled touch events on the document object.
*
* Firefox v8.01 (and possibly others) exhibited strange behavior when
* mounting `onmousemove` events at some node that was not the document
* element. The symptoms were that if your mouse is not moving over something
* contained within that mount point (for example on the background) the
* top-level listeners for `onmousemove` won't be called. However, if you
* register the `mousemove` on the document object, then it will of course
* catch all `mousemove`s. This along with iOS quirks, justifies restricting
* top-level listeners to the document object only, at least for these
* movement types of events and possibly all events.
*
* @see http://www.quirksmode.org/blog/archives/2010/09/click_event_del.html
*
* Also, `keyup`/`keypress`/`keydown` do not bubble to the window on IE, but
* they bubble to document.
*
* @param {string} registrationName Name of listener (e.g. `onClick`).
* @param {object} contentDocumentHandle Document which owns the container
*/
listenTo: function (registrationName, contentDocumentHandle) {
var mountAt = contentDocumentHandle;
var isListening = getListeningForDocument(mountAt);
var dependencies = EventPluginRegistry.registrationNameDependencies[registrationName];
var topLevelTypes = EventConstants.topLevelTypes;
for (var i = 0; i < dependencies.length; i++) {
var dependency = dependencies[i];
if (!(isListening.hasOwnProperty(dependency) && isListening[dependency])) {
if (dependency === topLevelTypes.topWheel) {
if (isEventSupported('wheel')) {
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topWheel, 'wheel', mountAt);
} else if (isEventSupported('mousewheel')) {
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topWheel, 'mousewheel', mountAt);
} else {
// Firefox needs to capture a different mouse scroll event.
// @see http://www.quirksmode.org/dom/events/tests/scroll.html
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topWheel, 'DOMMouseScroll', mountAt);
}
} else if (dependency === topLevelTypes.topScroll) {
if (isEventSupported('scroll', true)) {
ReactBrowserEventEmitter.ReactEventListener.trapCapturedEvent(topLevelTypes.topScroll, 'scroll', mountAt);
} else {
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topScroll, 'scroll', ReactBrowserEventEmitter.ReactEventListener.WINDOW_HANDLE);
}
} else if (dependency === topLevelTypes.topFocus || dependency === topLevelTypes.topBlur) {
if (isEventSupported('focus', true)) {
ReactBrowserEventEmitter.ReactEventListener.trapCapturedEvent(topLevelTypes.topFocus, 'focus', mountAt);
ReactBrowserEventEmitter.ReactEventListener.trapCapturedEvent(topLevelTypes.topBlur, 'blur', mountAt);
} else if (isEventSupported('focusin')) {
// IE has `focusin` and `focusout` events which bubble.
// @see http://www.quirksmode.org/blog/archives/2008/04/delegating_the.html
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topFocus, 'focusin', mountAt);
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelTypes.topBlur, 'focusout', mountAt);
}
// to make sure blur and focus event listeners are only attached once
isListening[topLevelTypes.topBlur] = true;
isListening[topLevelTypes.topFocus] = true;
} else if (topEventMapping.hasOwnProperty(dependency)) {
ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(dependency, topEventMapping[dependency], mountAt);
}
isListening[dependency] = true;
}
}
},
trapBubbledEvent: function (topLevelType, handlerBaseName, handle) {
return ReactBrowserEventEmitter.ReactEventListener.trapBubbledEvent(topLevelType, handlerBaseName, handle);
},
trapCapturedEvent: function (topLevelType, handlerBaseName, handle) {
return ReactBrowserEventEmitter.ReactEventListener.trapCapturedEvent(topLevelType, handlerBaseName, handle);
},
/**
* Listens to window scroll and resize events. We cache scroll values so that
* application code can access them without triggering reflows.
*
* NOTE: Scroll events do not bubble.
*
* @see http://www.quirksmode.org/dom/events/scroll.html
*/
ensureScrollValueMonitoring: function () {
if (!isMonitoringScrollValue) {
var refresh = ViewportMetrics.refreshScrollValues;
ReactBrowserEventEmitter.ReactEventListener.monitorScrollValue(refresh);
isMonitoringScrollValue = true;
}
},
eventNameDispatchConfigs: EventPluginHub.eventNameDispatchConfigs,
registrationNameModules: EventPluginHub.registrationNameModules,
putListener: EventPluginHub.putListener,
getListener: EventPluginHub.getListener,
deleteListener: EventPluginHub.deleteListener,
deleteAllListeners: EventPluginHub.deleteAllListeners
});
ReactPerf.measureMethods(ReactBrowserEventEmitter, 'ReactBrowserEventEmitter', {
putListener: 'putListener',
deleteListener: 'deleteListener'
});
module.exports = ReactBrowserEventEmitter;