gecko-dev/browser/base/content/newtab/cells.js

127 строки
3.0 KiB
JavaScript

#ifdef 0
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#endif
/**
* This class manages a cell's DOM node (not the actually cell content, a site).
* It's mostly read-only, i.e. all manipulation of both position and content
* aren't handled here.
*/
function Cell(aGrid, aNode) {
this._grid = aGrid;
this._node = aNode;
this._node._newtabCell = this;
// Register drag-and-drop event handlers.
["dragenter", "dragover", "dragexit", "drop"].forEach(function (aType) {
this._node.addEventListener(aType, this, false);
}, this);
}
Cell.prototype = {
/**
* The grid.
*/
_grid: null,
/**
* The cell's DOM node.
*/
get node() { return this._node; },
/**
* The cell's offset in the grid.
*/
get index() {
let index = this._grid.cells.indexOf(this);
// Cache this value, overwrite the getter.
Object.defineProperty(this, "index", {value: index, enumerable: true});
return index;
},
/**
* The previous cell in the grid.
*/
get previousSibling() {
let prev = this.node.previousElementSibling;
prev = prev && prev._newtabCell;
// Cache this value, overwrite the getter.
Object.defineProperty(this, "previousSibling", {value: prev, enumerable: true});
return prev;
},
/**
* The next cell in the grid.
*/
get nextSibling() {
let next = this.node.nextElementSibling;
next = next && next._newtabCell;
// Cache this value, overwrite the getter.
Object.defineProperty(this, "nextSibling", {value: next, enumerable: true});
return next;
},
/**
* The site contained in the cell, if any.
*/
get site() {
let firstChild = this.node.firstElementChild;
return firstChild && firstChild._newtabSite;
},
/**
* Checks whether the cell contains a pinned site.
* @return Whether the cell contains a pinned site.
*/
containsPinnedSite: function Cell_containsPinnedSite() {
let site = this.site;
return site && site.isPinned();
},
/**
* Checks whether the cell contains a site (is empty).
* @return Whether the cell is empty.
*/
isEmpty: function Cell_isEmpty() {
return !this.site;
},
/**
* Handles all cell events.
*/
handleEvent: function Cell_handleEvent(aEvent) {
// We're not responding to external drag/drop events
// when our parent window is in private browsing mode.
if (inPrivateBrowsingMode() && !gDrag.draggedSite)
return;
if (aEvent.type != "dragexit" && !gDrag.isValid(aEvent))
return;
switch (aEvent.type) {
case "dragenter":
aEvent.preventDefault();
gDrop.enter(this, aEvent);
break;
case "dragover":
aEvent.preventDefault();
break;
case "dragexit":
gDrop.exit(this, aEvent);
break;
case "drop":
aEvent.preventDefault();
gDrop.drop(this, aEvent);
break;
}
}
};