d2-ui
Version:
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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 ReactEventListener
* @typechecks static-only
*/
;
var EventListener = require('fbjs/lib/EventListener');
var ExecutionEnvironment = require('fbjs/lib/ExecutionEnvironment');
var PooledClass = require('./PooledClass');
var ReactInstanceHandles = require('./ReactInstanceHandles');
var ReactMount = require('./ReactMount');
var ReactUpdates = require('./ReactUpdates');
var assign = require('./Object.assign');
var getEventTarget = require('./getEventTarget');
var getUnboundedScrollPosition = require('fbjs/lib/getUnboundedScrollPosition');
var DOCUMENT_FRAGMENT_NODE_TYPE = 11;
/**
* Finds the parent React component of `node`.
*
* @param {*} node
* @return {?DOMEventTarget} Parent container, or `null` if the specified node
* is not nested.
*/
function findParent(node) {
// TODO: It may be a good idea to cache this to prevent unnecessary DOM
// traversal, but caching is difficult to do correctly without using a
// mutation observer to listen for all DOM changes.
var nodeID = ReactMount.getID(node);
var rootID = ReactInstanceHandles.getReactRootIDFromNodeID(nodeID);
var container = ReactMount.findReactContainerForID(rootID);
var parent = ReactMount.getFirstReactDOM(container);
return parent;
}
// Used to store ancestor hierarchy in top level callback
function TopLevelCallbackBookKeeping(topLevelType, nativeEvent) {
this.topLevelType = topLevelType;
this.nativeEvent = nativeEvent;
this.ancestors = [];
}
assign(TopLevelCallbackBookKeeping.prototype, {
destructor: function () {
this.topLevelType = null;
this.nativeEvent = null;
this.ancestors.length = 0;
}
});
PooledClass.addPoolingTo(TopLevelCallbackBookKeeping, PooledClass.twoArgumentPooler);
function handleTopLevelImpl(bookKeeping) {
// TODO: Re-enable event.path handling
//
// if (bookKeeping.nativeEvent.path && bookKeeping.nativeEvent.path.length > 1) {
// // New browsers have a path attribute on native events
// handleTopLevelWithPath(bookKeeping);
// } else {
// // Legacy browsers don't have a path attribute on native events
// handleTopLevelWithoutPath(bookKeeping);
// }
void handleTopLevelWithPath; // temporarily unused
handleTopLevelWithoutPath(bookKeeping);
}
// Legacy browsers don't have a path attribute on native events
function handleTopLevelWithoutPath(bookKeeping) {
var topLevelTarget = ReactMount.getFirstReactDOM(getEventTarget(bookKeeping.nativeEvent)) || window;
// Loop through the hierarchy, in case there's any nested components.
// It's important that we build the array of ancestors before calling any
// event handlers, because event handlers can modify the DOM, leading to
// inconsistencies with ReactMount's node cache. See #1105.
var ancestor = topLevelTarget;
while (ancestor) {
bookKeeping.ancestors.push(ancestor);
ancestor = findParent(ancestor);
}
for (var i = 0; i < bookKeeping.ancestors.length; i++) {
topLevelTarget = bookKeeping.ancestors[i];
var topLevelTargetID = ReactMount.getID(topLevelTarget) || '';
ReactEventListener._handleTopLevel(bookKeeping.topLevelType, topLevelTarget, topLevelTargetID, bookKeeping.nativeEvent, getEventTarget(bookKeeping.nativeEvent));
}
}
// New browsers have a path attribute on native events
function handleTopLevelWithPath(bookKeeping) {
var path = bookKeeping.nativeEvent.path;
var currentNativeTarget = path[0];
var eventsFired = 0;
for (var i = 0; i < path.length; i++) {
var currentPathElement = path[i];
if (currentPathElement.nodeType === DOCUMENT_FRAGMENT_NODE_TYPE) {
currentNativeTarget = path[i + 1];
}
// TODO: slow
var reactParent = ReactMount.getFirstReactDOM(currentPathElement);
if (reactParent === currentPathElement) {
var currentPathElementID = ReactMount.getID(currentPathElement);
var newRootID = ReactInstanceHandles.getReactRootIDFromNodeID(currentPathElementID);
bookKeeping.ancestors.push(currentPathElement);
var topLevelTargetID = ReactMount.getID(currentPathElement) || '';
eventsFired++;
ReactEventListener._handleTopLevel(bookKeeping.topLevelType, currentPathElement, topLevelTargetID, bookKeeping.nativeEvent, currentNativeTarget);
// Jump to the root of this React render tree
while (currentPathElementID !== newRootID) {
i++;
currentPathElement = path[i];
currentPathElementID = ReactMount.getID(currentPathElement);
}
}
}
if (eventsFired === 0) {
ReactEventListener._handleTopLevel(bookKeeping.topLevelType, window, '', bookKeeping.nativeEvent, getEventTarget(bookKeeping.nativeEvent));
}
}
function scrollValueMonitor(cb) {
var scrollPosition = getUnboundedScrollPosition(window);
cb(scrollPosition);
}
var ReactEventListener = {
_enabled: true,
_handleTopLevel: null,
WINDOW_HANDLE: ExecutionEnvironment.canUseDOM ? window : null,
setHandleTopLevel: function (handleTopLevel) {
ReactEventListener._handleTopLevel = handleTopLevel;
},
setEnabled: function (enabled) {
ReactEventListener._enabled = !!enabled;
},
isEnabled: function () {
return ReactEventListener._enabled;
},
/**
* Traps top-level events by using event bubbling.
*
* @param {string} topLevelType Record from `EventConstants`.
* @param {string} handlerBaseName Event name (e.g. "click").
* @param {object} handle Element on which to attach listener.
* @return {?object} An object with a remove function which will forcefully
* remove the listener.
* @internal
*/
trapBubbledEvent: function (topLevelType, handlerBaseName, handle) {
var element = handle;
if (!element) {
return null;
}
return EventListener.listen(element, handlerBaseName, ReactEventListener.dispatchEvent.bind(null, topLevelType));
},
/**
* Traps a top-level event by using event capturing.
*
* @param {string} topLevelType Record from `EventConstants`.
* @param {string} handlerBaseName Event name (e.g. "click").
* @param {object} handle Element on which to attach listener.
* @return {?object} An object with a remove function which will forcefully
* remove the listener.
* @internal
*/
trapCapturedEvent: function (topLevelType, handlerBaseName, handle) {
var element = handle;
if (!element) {
return null;
}
return EventListener.capture(element, handlerBaseName, ReactEventListener.dispatchEvent.bind(null, topLevelType));
},
monitorScrollValue: function (refresh) {
var callback = scrollValueMonitor.bind(null, refresh);
EventListener.listen(window, 'scroll', callback);
},
dispatchEvent: function (topLevelType, nativeEvent) {
if (!ReactEventListener._enabled) {
return;
}
var bookKeeping = TopLevelCallbackBookKeeping.getPooled(topLevelType, nativeEvent);
try {
// Event queue being processed in the same cycle allows
// `preventDefault`.
ReactUpdates.batchedUpdates(handleTopLevelImpl, bookKeeping);
} finally {
TopLevelCallbackBookKeeping.release(bookKeeping);
}
}
};
module.exports = ReactEventListener;