widget/nsBaseDragService.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef nsBaseDragService_h__
   7 #define nsBaseDragService_h__
   8
   9 #include "nsIDragService.h"
  10 #include "nsIDragSession.h"
  11 #include "nsCOMPtr.h"
  12 #include "nsRect.h"
  13 #include "nsPoint.h"
  14 #include "nsString.h"
  15 #include "mozilla/RefPtr.h"
  16 #include "mozilla/dom/ContentParent.h"
  17 #include "mozilla/dom/HTMLCanvasElement.h"
  18 #include "mozilla/dom/RemoteDragStartData.h"
  19 #include "mozilla/Logging.h"
  20 #include "nsTArray.h"
  21 #include "nsRegion.h"
  22 #include "Units.h"
  23
  24 extern mozilla::LazyLogModule sWidgetDragServiceLog;
  25 #define MOZ_DRAGSERVICE_LOG(...) \
  26   MOZ_LOG(sWidgetDragServiceLog, mozilla::LogLevel::Debug, (__VA_ARGS__))
  27 #define MOZ_DRAGSERVICE_LOG_ENABLED() \
  28   MOZ_LOG_TEST(sWidgetDragServiceLog, mozilla::LogLevel::Debug)
  29
  30 // translucency level for drag images
  31 #define DRAG_TRANSLUCENCY 0.65
  32
  33 class nsIContent;
  34
  35 class nsINode;
  36 class nsPresContext;
  37 class nsIImageLoadingContent;
  38
  39 namespace mozilla {
  40 namespace gfx {
  41 class SourceSurface;
  42 }  // namespace gfx
  43
  44 namespace dom {
  45 class DataTransfer;
  46 class Selection;
  47 }  // namespace dom
  48 }  // namespace mozilla
  49
  50 /**
  51  * XP DragService wrapper base class
  52  */
  53
  54 class nsBaseDragService : public nsIDragService, public nsIDragSession {
  55  public:
  56   typedef mozilla::gfx::SourceSurface SourceSurface;
  57
  58   nsBaseDragService();
  59
  60   // nsISupports
  61   NS_DECL_ISUPPORTS
  62
  63   // nsIDragSession and nsIDragService
  64   NS_DECL_NSIDRAGSERVICE
  65   NS_DECL_NSIDRAGSESSION
  66
  67   void SetDragEndPoint(nsIntPoint aEndDragPoint) {
  68     mEndDragPoint =
  69         mozilla::LayoutDeviceIntPoint::FromUnknownPoint(aEndDragPoint);
  70   }
  71   void SetDragEndPoint(mozilla::LayoutDeviceIntPoint aEndDragPoint) {
  72     mEndDragPoint = aEndDragPoint;
  73   }
  74
  75   uint16_t GetInputSource() { return mInputSource; }
  76
  77   int32_t TakeChildProcessDragAction();
  78
  79  protected:
  80   virtual ~nsBaseDragService();
  81
  82   /**
  83    * Called from nsBaseDragService to initiate a platform drag from a source
  84    * in this process.  This is expected to ensure that StartDragSession() and
  85    * EndDragSession() get called if the platform drag is successfully invoked.
  86    */
  87   MOZ_CAN_RUN_SCRIPT virtual nsresult InvokeDragSessionImpl(
  88       nsIArray* aTransferableArray,
  89       const mozilla::Maybe<mozilla::CSSIntRegion>& aRegion,
  90       uint32_t aActionType) = 0;
  91
  92   /**
  93    * Draw the drag image, if any, to a surface and return it. The drag image
  94    * is constructed from mImage if specified, or aDOMNode if mImage is null.
  95    *
  96    * aRegion may be used to draw only a subset of the element. This region
  97    * should be supplied using x and y coordinates measured in css pixels
  98    * that are relative to the upper-left corner of the window.
  99    *
 100    * aScreenPosition should be the screen coordinates of the mouse click
 101    * for the drag. These are in CSS pixels.
 102    *
 103    * On return, aScreenDragRect will contain the screen coordinates of the
 104    * area being dragged. This is used by the platform-specific part of the
 105    * drag service to determine the drag feedback. This rect will be in the
 106    * device pixels of the presContext.
 107    *
 108    * If there is no drag image, the returned surface will be null, but
 109    * aScreenDragRect will still be set to the drag area.
 110    *
 111    * aPresContext will be set to the nsPresContext used determined from
 112    * whichever of mImage or aDOMNode is used.
 113    */
 114   nsresult DrawDrag(nsINode* aDOMNode,
 115                     const mozilla::Maybe<mozilla::CSSIntRegion>& aRegion,
 116                     mozilla::CSSIntPoint aScreenPosition,
 117                     mozilla::LayoutDeviceIntRect* aScreenDragRect,
 118                     RefPtr<SourceSurface>* aSurface,
 119                     nsPresContext** aPresContext);
 120
 121   /**
 122    * Draw a drag image for an image node specified by aImageLoader or aCanvas.
 123    * This is called by DrawDrag.
 124    */
 125   nsresult DrawDragForImage(nsPresContext* aPresContext,
 126                             nsIImageLoadingContent* aImageLoader,
 127                             mozilla::dom::HTMLCanvasElement* aCanvas,
 128                             mozilla::LayoutDeviceIntRect* aScreenDragRect,
 129                             RefPtr<SourceSurface>* aSurface);
 130
 131   /**
 132    * If the drag image is a popup, open the popup when the drag begins.
 133    */
 134   void OpenDragPopup();
 135
 136   /**
 137    * Free resources contained in DataTransferItems that aren't needed by JS.
 138    */
 139   void DiscardInternalTransferData();
 140
 141   // Returns true if a drag event was dispatched to a child process after
 142   // the previous TakeDragEventDispatchedToChildProcess() call.
 143   bool TakeDragEventDispatchedToChildProcess() {
 144     bool retval = mDragEventDispatchedToChildProcess;
 145     mDragEventDispatchedToChildProcess = false;
 146     return retval;
 147   }
 148
 149   bool mCanDrop;
 150   bool mOnlyChromeDrop;
 151   bool mDoingDrag;
 152   bool mSessionIsSynthesizedForTests;
 153   bool mIsDraggingTextInTextControl;
 154
 155   // true if in EndDragSession
 156   bool mEndingSession;
 157   // true if mImage should be used to set a drag image
 158   bool mHasImage;
 159   // true if the user cancelled the drag operation
 160   bool mUserCancelled;
 161
 162   bool mDragEventDispatchedToChildProcess;
 163
 164   uint32_t mDragAction;
 165   uint32_t mDragActionFromChildProcess;
 166
 167   // mEffectAllowedForTests stores allowed effects at invoking the drag
 168   // for tests.
 169   uint32_t mEffectAllowedForTests;
 170
 171   nsCOMPtr<nsINode> mSourceNode;
 172   nsCOMPtr<nsIPrincipal> mTriggeringPrincipal;
 173   nsCOMPtr<nsIContentSecurityPolicy> mCsp;
 174
 175   // the document at the drag source. will be null if it came from outside the
 176   // app.
 177   RefPtr<mozilla::dom::Document> mSourceDocument;
 178
 179   RefPtr<mozilla::dom::WindowContext> mSourceWindowContext;
 180   RefPtr<mozilla::dom::WindowContext> mSourceTopWindowContext;
 181
 182   // the contentpolicy type passed to the channel when initiating the drag
 183   // session
 184   nsContentPolicyType mContentPolicyType;
 185
 186   RefPtr<mozilla::dom::DataTransfer> mDataTransfer;
 187
 188   // used to determine the image to appear on the cursor while dragging
 189   nsCOMPtr<nsINode> mImage;
 190   // offset of cursor within the image
 191   mozilla::CSSIntPoint mImageOffset;
 192
 193   // set if a selection is being dragged
 194   RefPtr<mozilla::dom::Selection> mSelection;
 195
 196   // remote drag data
 197   RefPtr<mozilla::dom::RemoteDragStartData> mDragStartData;
 198
 199   // set if the image in mImage is a popup. If this case, the popup will be
 200   // opened and moved instead of using a drag image.
 201   nsCOMPtr<mozilla::dom::Element> mDragPopup;
 202
 203   // the screen position where drag gesture occurred, used for positioning the
 204   // drag image.
 205   mozilla::CSSIntPoint mScreenPosition;
 206
 207   // The position relative to the top level widget where the drag ended.
 208   mozilla::LayoutDeviceIntPoint mEndDragPoint;
 209
 210   uint32_t mSuppressLevel;
 211
 212   // The input source of the drag event. Possible values are from MouseEvent.
 213   uint16_t mInputSource;
 214
 215   nsTArray<RefPtr<mozilla::dom::ContentParent>> mChildProcesses;
 216
 217   // Sub-region for tree-selections.
 218   mozilla::Maybe<mozilla::CSSIntRegion> mRegion;
 219 };
 220
 221 #endif  // nsBaseDragService_h__