/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is mozilla.org code. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Ben Goodger (Original Author) * Pierre Chanial * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ //////////////////////////////////////////////////////////////////////////// // XXX - WARNING - DRAG AND DROP API CHANGE ALERT - XXX // This file has been extensively modified in a checkin planned for Mozilla // 0.8, and the API has been modified. DO NOT MODIFY THIS FILE without // approval from ben@netscape.com, otherwise your changes will be lost. /** * XXX - until load is supported in chrome, you also need to include * these files: * chrome://global/content/nsTransferable.js **/ /** * nsDragAndDrop - a convenience wrapper for nsTransferable, nsITransferable * and nsIDragService/nsIDragSession. * * Use: map the handler functions to the 'ondraggesture', 'ondragover' and * 'ondragdrop' event handlers on your XML element, e.g. * * * You need to create an observer js object with the following member * functions: * Object onDragStart (event) // called when drag initiated, * // returns flavour list with data * // to stuff into transferable * void onDragOver (Object flavour) // called when element is dragged * // over, so that it can perform * // any drag-over feedback for provided * // flavour * void onDrop (Object data) // formatted data object dropped. * Object getSupportedFlavours () // returns a flavour list so that * // nsTransferable can determine * // whether or not to accept drop. **/ var nsDragAndDrop = { _mDS: null, get mDragService() { if (!this._mDS) { const kDSContractID = "@mozilla.org/widget/dragservice;1"; const kDSIID = Components.interfaces.nsIDragService; this._mDS = Components.classes[kDSContractID].getService(kDSIID); } return this._mDS; }, /** * void startDrag (DOMEvent aEvent, Object aDragDropObserver) ; * * called when a drag on an element is started. * * @param DOMEvent aEvent * the DOM event fired by the drag init * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ startDrag: function (aEvent, aDragDropObserver) { if (!("onDragStart" in aDragDropObserver)) return; const kDSIID = Components.interfaces.nsIDragService; var dragAction = { action: kDSIID.DRAGDROP_ACTION_COPY + kDSIID.DRAGDROP_ACTION_MOVE + kDSIID.DRAGDROP_ACTION_LINK }; var transferData = { data: null }; try { aDragDropObserver.onDragStart(aEvent, transferData, dragAction); } catch (e) { return; // not a draggable item, bail! } if (!transferData.data) return; transferData = transferData.data; var transArray = Components.classes["@mozilla.org/supports-array;1"] .createInstance(Components.interfaces.nsISupportsArray); var region = null; if (aEvent.originalTarget.localName == "treechildren") { // let's build the drag region var tree = aEvent.originalTarget.parentNode; try { region = Components.classes["@mozilla.org/gfx/region;1"].createInstance(Components.interfaces.nsIScriptableRegion); region.init(); var obo = tree.treeBoxObject; var bo = obo.treeBody.boxObject; var sel= tree.view.selection; var rowX = bo.x; var rowY = bo.y; var rowHeight = obo.rowHeight; var rowWidth = bo.width; //add a rectangle for each visible selected row for (var i = obo.getFirstVisibleRow(); i <= obo.getLastVisibleRow(); i ++) { if (sel.isSelected(i)) region.unionRect(rowX, rowY, rowWidth, rowHeight); rowY = rowY + rowHeight; } //and finally, clip the result to be sure we don't spill over... region.intersectRect(bo.x, bo.y, bo.width, bo.height); } catch(ex) { dump("Error while building selection region: " + ex + "\n"); region = null; } } var count = 0; do { var trans = nsTransferable.set(transferData._XferID == "TransferData" ? transferData : transferData.dataList[count++]); transArray.AppendElement(trans.QueryInterface(Components.interfaces.nsISupports)); } while (transferData._XferID == "TransferDataSet" && count < transferData.dataList.length); try { this.mDragService.invokeDragSession(aEvent.target, transArray, region, dragAction.action); } catch(ex) { // this could be because the user pressed escape to // cancel the drag. even if it's not, there's not much // we can do, so be silent. } aEvent.stopPropagation(); }, /** * void dragOver (DOMEvent aEvent, Object aDragDropObserver) ; * * called when a drag passes over this element * * @param DOMEvent aEvent * the DOM event fired by passing over the element * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ dragOver: function (aEvent, aDragDropObserver) { if (!("onDragOver" in aDragDropObserver)) return; if (!this.checkCanDrop(aEvent, aDragDropObserver)) return; var flavourSet = aDragDropObserver.getSupportedFlavours(); for (var flavour in flavourSet.flavourTable) { if (this.mDragSession.isDataFlavorSupported(flavour)) { aDragDropObserver.onDragOver(aEvent, flavourSet.flavourTable[flavour], this.mDragSession); aEvent.stopPropagation(); break; } } }, mDragSession: null, /** * void drop (DOMEvent aEvent, Object aDragDropObserver) ; * * called when the user drops on the element * * @param DOMEvent aEvent * the DOM event fired by the drop * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ drop: function (aEvent, aDragDropObserver) { if (!("onDrop" in aDragDropObserver)) return; if (!this.checkCanDrop(aEvent, aDragDropObserver)) return; if (this.mDragSession.canDrop) { var flavourSet = aDragDropObserver.getSupportedFlavours(); var transferData = nsTransferable.get(flavourSet, this.getDragData, true); // hand over to the client to respond to dropped data var multiple = "canHandleMultipleItems" in aDragDropObserver && aDragDropObserver.canHandleMultipleItems; var dropData = multiple ? transferData : transferData.first.first; aDragDropObserver.onDrop(aEvent, dropData, this.mDragSession); } aEvent.stopPropagation(); }, /** * void dragExit (DOMEvent aEvent, Object aDragDropObserver) ; * * called when a drag leaves this element * * @param DOMEvent aEvent * the DOM event fired by leaving the element * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ dragExit: function (aEvent, aDragDropObserver) { if (!this.checkCanDrop(aEvent, aDragDropObserver)) return; if ("onDragExit" in aDragDropObserver) aDragDropObserver.onDragExit(aEvent, this.mDragSession); }, /** * void dragEnter (DOMEvent aEvent, Object aDragDropObserver) ; * * called when a drag enters in this element * * @param DOMEvent aEvent * the DOM event fired by entering in the element * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ dragEnter: function (aEvent, aDragDropObserver) { if (!this.checkCanDrop(aEvent, aDragDropObserver)) return; if ("onDragEnter" in aDragDropObserver) aDragDropObserver.onDragEnter(aEvent, this.mDragSession); }, /** * nsISupportsArray getDragData (Object aFlavourList) * * Creates a nsISupportsArray of all droppable items for the given * set of supported flavours. * * @param FlavourSet aFlavourSet * formatted flavour list. **/ getDragData: function (aFlavourSet) { var supportsArray = Components.classes["@mozilla.org/supports-array;1"] .createInstance(Components.interfaces.nsISupportsArray); for (var i = 0; i < nsDragAndDrop.mDragSession.numDropItems; ++i) { var trans = nsTransferable.createTransferable(); for (var j = 0; j < aFlavourSet.flavours.length; ++j) trans.addDataFlavor(aFlavourSet.flavours[j].contentType); nsDragAndDrop.mDragSession.getData(trans, i); supportsArray.AppendElement(trans); } return supportsArray; }, /** * Boolean checkCanDrop (DOMEvent aEvent, Object aDragDropObserver) ; * * Sets the canDrop attribute for the drag session. * returns false if there is no current drag session. * * @param DOMEvent aEvent * the DOM event fired by the drop * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. **/ checkCanDrop: function (aEvent, aDragDropObserver) { if (!this.mDragSession) this.mDragSession = this.mDragService.getCurrentSession(); if (!this.mDragSession) return false; this.mDragSession.canDrop = this.mDragSession.sourceNode != aEvent.target; if ("canDrop" in aDragDropObserver) this.mDragSession.canDrop &= aDragDropObserver.canDrop(aEvent, this.mDragSession); return true; }, /** * Do a security check for drag n' drop. Make sure the source document * can load the dragged link. * * @param DOMEvent aEvent * the DOM event fired by leaving the element * @param Object aDragDropObserver * javascript object of format described above that specifies * the way in which the element responds to drag events. * @param String aUri * the uri being dragged **/ dragDropSecurityCheck: function (aEvent, aDragSession, aUri) { var sourceDoc = aDragSession.sourceDocument; if (sourceDoc) { // Strip leading and trailing whitespace, then try to create a // URI from the dropped string. If that succeeds, we're // dropping a URI and we need to do a security check to make // sure the source document can load the dropped URI. We don't // so much care about creating the real URI here // (i.e. encoding differences etc don't matter), we just want // to know if aUri really is a URI. var uriStr = aUri.replace(/^\s*|\s*$/g, ''); var uri = null; try { uri = Components.classes["@mozilla.org/network/io-service;1"] .getService(Components.interfaces.nsIIOService) .newURI(uriStr, null, null); } catch (e) { } if (uri) { // aUri is a URI, do the security check. var sourceURI = sourceDoc.documentURI; const nsIScriptSecurityManager = Components.interfaces.nsIScriptSecurityManager; var secMan = Components.classes["@mozilla.org/scriptsecuritymanager;1"] .getService(nsIScriptSecurityManager); try { secMan.checkLoadURIStr(sourceURI, uriStr, nsIScriptSecurityManager.STANDARD); } catch (e) { // Stop event propagation right here. aEvent.stopPropagation(); throw "Drop of " + aUri + " denied."; } } } } };