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// Copyright (c) 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
/**
* @unrestricted
*/
UI.DropTarget = class {
/**
* @param {!Element} element
* @param {!Array.<string>} transferTypes
* @param {string} messageText
* @param {function(!DataTransfer)} handleDrop
*/
constructor(element, transferTypes, messageText, handleDrop) {
element.addEventListener('dragenter', this._onDragEnter.bind(this), true);
element.addEventListener('dragover', this._onDragOver.bind(this), true);
this._element = element;
this._transferTypes = transferTypes;
this._messageText = messageText;
this._handleDrop = handleDrop;
this._enabled = true;
}
/**
* @param {boolean} enabled
*/
setEnabled(enabled) {
this._enabled = enabled;
}
/**
* @param {!Event} event
*/
_onDragEnter(event) {
if (this._enabled && this._hasMatchingType(event))
event.consume(true);
}
/**
* @param {!Event} event
* @return {boolean}
*/
_hasMatchingType(event) {
for (var type of this._transferTypes) {
if (event.dataTransfer.types.indexOf(type) !== -1)
return true;
}
return false;
}
/**
* @param {!Event} event
*/
_onDragOver(event) {
if (!this._enabled || !this._hasMatchingType(event))
return;
event.dataTransfer.dropEffect = 'copy';
event.consume(true);
if (this._dragMaskElement)
return;
this._dragMaskElement = this._element.createChild('div', '');
var shadowRoot = UI.createShadowRootWithCoreStyles(this._dragMaskElement, 'ui/dropTarget.css');
shadowRoot.createChild('div', 'drop-target-message').textContent = this._messageText;
this._dragMaskElement.addEventListener('drop', this._onDrop.bind(this), true);
this._dragMaskElement.addEventListener('dragleave', this._onDragLeave.bind(this), true);
}
/**
* @param {!Event} event
*/
_onDrop(event) {
event.consume(true);
this._removeMask();
if (this._enabled)
this._handleDrop(event.dataTransfer);
}
/**
* @param {!Event} event
*/
_onDragLeave(event) {
event.consume(true);
this._removeMask();
}
_removeMask() {
this._dragMaskElement.remove();
delete this._dragMaskElement;
}
};
UI.DropTarget.Types = {
Files: 'Files',
URIList: 'text/uri-list'
};
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