gecko-dev/toolkit/modules/WindowDraggingUtils.jsm

71 строка
2.3 KiB
JavaScript

/* 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/. */
ChromeUtils.import("resource://gre/modules/AppConstants.jsm");
const HAVE_CSS_WINDOW_DRAG_SUPPORT = ["win", "macosx"].includes(AppConstants.platform);
var EXPORTED_SYMBOLS = [ "WindowDraggingElement" ];
function WindowDraggingElement(elem) {
if (HAVE_CSS_WINDOW_DRAG_SUPPORT) {
return;
}
this._elem = elem;
this._window = elem.ownerGlobal;
this._elem.addEventListener("mousedown", this);
}
WindowDraggingElement.prototype = {
mouseDownCheck(e) { return true; },
dragTags: ["box", "hbox", "vbox", "spacer", "label", "statusbarpanel", "stack",
"toolbaritem", "toolbarseparator", "toolbarspring", "toolbarspacer",
"radiogroup", "deck", "scrollbox", "arrowscrollbox", "tabs"],
shouldDrag(aEvent) {
if (aEvent.button != 0 ||
this._window.fullScreen ||
!this.mouseDownCheck.call(this._elem, aEvent) ||
aEvent.defaultPrevented)
return false;
let target = aEvent.originalTarget, parent = aEvent.originalTarget;
// The target may be inside an embedded iframe or browser. (bug 615152)
if (target.ownerGlobal != this._window)
return false;
while (parent != this._elem) {
let mousethrough = parent.getAttribute("mousethrough");
if (mousethrough == "always")
target = parent.parentNode;
else if (mousethrough == "never")
break;
parent = parent.parentNode;
}
while (target != this._elem) {
if (!this.dragTags.includes(target.localName))
return false;
target = target.parentNode;
}
return true;
},
handleEvent(aEvent) {
switch (aEvent.type) {
case "mousedown":
if (this.shouldDrag(aEvent)) {
this._window.addEventListener("mousemove", this, { once: true });
this._window.addEventListener("mouseup", this, { once: true });
}
break;
case "mousemove":
this._window.beginWindowMove(aEvent);
this._window.removeEventListener("mouseup", this);
break;
case "mouseup":
this._window.removeEventListener("mousemove", this);
break;
}
}
};