widget/nsBaseDragService.h
author Jim Chen <nchen@mozilla.com>
Wed, 20 Jun 2018 16:46:20 -0400
changeset 423113 2806729c61eaac199ad4670788c4008079a99f34
parent 420385 7161cb18122e3f51c30a014d688a4c5fbcacaa74
child 430721 b2955b86592b030822d771f990c155b2dee75e08
permissions -rw-r--r--
Bug 1469683 - 1. Fix crash tests; r=esawin Specify individual sessions in crash tests (i.e. "mainSession.waitUntilCalled" instead of "sessionRule.waitUntilCalled"), so that the tests assert behavior on the correct session, and not inadvertently on the cached session. Also, under x86 debug builds, Gecko installs an "ah_crap_handler" for SIGSEGV that waits for a long time, which causes our crash tests to time out. Therefore, ignore crash tests under x86 debug. MozReview-Commit-ID: DdtmRBLmPGp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */

#ifndef nsBaseDragService_h__
#define nsBaseDragService_h__

#include "nsIDragService.h"
#include "nsIDragSession.h"
#include "nsITransferable.h"
#include "nsCOMPtr.h"
#include "nsRect.h"
#include "nsPoint.h"
#include "nsString.h"
#include "mozilla/RefPtr.h"
#include "mozilla/dom/ContentParent.h"
#include "mozilla/dom/HTMLCanvasElement.h"
#include "nsTArray.h"
#include "Units.h"

// translucency level for drag images
#define DRAG_TRANSLUCENCY 0.65

class nsIContent;
class nsIDocument;
class nsINode;
class nsPresContext;
class nsIImageLoadingContent;

namespace mozilla {
namespace gfx {
class SourceSurface;
} // namespace gfx

namespace dom {
class DataTransfer;
class Selection;
} // namespace dom
} // namespace mozilla

/**
 * XP DragService wrapper base class
 */

class nsBaseDragService : public nsIDragService,
                          public nsIDragSession
{

public:
  typedef mozilla::gfx::SourceSurface SourceSurface;

  nsBaseDragService();

  //nsISupports
  NS_DECL_ISUPPORTS

  //nsIDragSession and nsIDragService
  NS_DECL_NSIDRAGSERVICE
  NS_DECL_NSIDRAGSESSION

  void SetDragEndPoint(nsIntPoint aEndDragPoint)
  {
    mEndDragPoint = mozilla::LayoutDeviceIntPoint::FromUnknownPoint(aEndDragPoint);
  }
  void SetDragEndPoint(mozilla::LayoutDeviceIntPoint aEndDragPoint)
  {
    mEndDragPoint = aEndDragPoint;
  }

  uint16_t GetInputSource() { return mInputSource; }

  int32_t TakeChildProcessDragAction();

protected:
  virtual ~nsBaseDragService();

  /**
   * Called from nsBaseDragService to initiate a platform drag from a source
   * in this process.  This is expected to ensure that StartDragSession() and
   * EndDragSession() get called if the platform drag is successfully invoked.
   */
  virtual nsresult InvokeDragSessionImpl(nsIArray* aTransferableArray,
                                         nsIScriptableRegion* aDragRgn,
                                         uint32_t aActionType) = 0;

  /**
   * Draw the drag image, if any, to a surface and return it. The drag image
   * is constructed from mImage if specified, or aDOMNode if mImage is null.
   *
   * aRegion may be used to draw only a subset of the element. This region
   * should be supplied using x and y coordinates measured in css pixels
   * that are relative to the upper-left corner of the window.
   *
   * aScreenPosition should be the screen coordinates of the mouse click
   * for the drag. These are in CSS pixels.
   *
   * On return, aScreenDragRect will contain the screen coordinates of the
   * area being dragged. This is used by the platform-specific part of the
   * drag service to determine the drag feedback. This rect will be in the
   * device pixels of the presContext.
   *
   * If there is no drag image, the returned surface will be null, but
   * aScreenDragRect will still be set to the drag area.
   *
   * aPresContext will be set to the nsPresContext used determined from
   * whichever of mImage or aDOMNode is used.
   */
  nsresult DrawDrag(nsINode* aDOMNode,
                    nsIScriptableRegion* aRegion,
                    mozilla::CSSIntPoint aScreenPosition,
                    mozilla::LayoutDeviceIntRect* aScreenDragRect,
                    RefPtr<SourceSurface>* aSurface,
                    nsPresContext **aPresContext);

  /**
   * Draw a drag image for an image node specified by aImageLoader or aCanvas.
   * This is called by DrawDrag.
   */
  nsresult DrawDragForImage(nsPresContext *aPresContext,
                            nsIImageLoadingContent* aImageLoader,
                            mozilla::dom::HTMLCanvasElement* aCanvas,
                            mozilla::LayoutDeviceIntRect* aScreenDragRect,
                            RefPtr<SourceSurface>* aSurface);

  /**
   * Convert aScreenPosition from CSS pixels into unscaled device pixels.
   */
  mozilla::LayoutDeviceIntPoint
  ConvertToUnscaledDevPixels(nsPresContext* aPresContext,
                             mozilla::CSSIntPoint aScreenPosition);

  /**
   * If the drag image is a popup, open the popup when the drag begins.
   */
  void OpenDragPopup();

  /**
   * Free resources contained in DataTransferItems that aren't needed by JS.
   */
  void DiscardInternalTransferData();

  // Returns true if a drag event was dispatched to a child process after
  // the previous TakeDragEventDispatchedToChildProcess() call.
  bool TakeDragEventDispatchedToChildProcess()
  {
    bool retval = mDragEventDispatchedToChildProcess;
    mDragEventDispatchedToChildProcess = false;
    return retval;
  }

  bool mCanDrop;
  bool mOnlyChromeDrop;
  bool mDoingDrag;
  // true if mImage should be used to set a drag image
  bool mHasImage;
  // true if the user cancelled the drag operation
  bool mUserCancelled;

  bool mDragEventDispatchedToChildProcess;

  uint32_t mDragAction;
  uint32_t mDragActionFromChildProcess;

  nsSize mTargetSize;
  nsCOMPtr<nsINode> mSourceNode;
  nsCString mTriggeringPrincipalURISpec;
  nsCOMPtr<nsIDocument> mSourceDocument;          // the document at the drag source. will be null
                                                  //  if it came from outside the app.
  nsContentPolicyType mContentPolicyType;         // the contentpolicy type passed to the channel
                                                  // when initiating the drag session
  RefPtr<mozilla::dom::DataTransfer> mDataTransfer;

  // used to determine the image to appear on the cursor while dragging
  nsCOMPtr<nsINode> mImage;
  // offset of cursor within the image
  mozilla::CSSIntPoint mImageOffset;

  // set if a selection is being dragged
  RefPtr<mozilla::dom::Selection> mSelection;

  // set if the image in mImage is a popup. If this case, the popup will be opened
  // and moved instead of using a drag image.
  nsCOMPtr<nsIContent> mDragPopup;

  // the screen position where drag gesture occurred, used for positioning the
  // drag image.
  mozilla::CSSIntPoint mScreenPosition;

  // the screen position where the drag ended
  mozilla::LayoutDeviceIntPoint mEndDragPoint;

  uint32_t mSuppressLevel;

  // The input source of the drag event. Possible values are from MouseEvent.
  uint16_t mInputSource;

  nsTArray<RefPtr<mozilla::dom::ContentParent>> mChildProcesses;
};

#endif // nsBaseDragService_h__