layout/xul/nsSliderFrame.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef nsSliderFrame_h__
   8 #define nsSliderFrame_h__
   9
  10 #include "mozilla/Attributes.h"
  11 #include "nsContainerFrame.h"
  12 #include "nsRepeatService.h"
  13 #include "nsAtom.h"
  14 #include "nsCOMPtr.h"
  15 #include "nsITimer.h"
  16 #include "nsIDOMEventListener.h"
  17
  18 class nsITimer;
  19 class nsScrollbarFrame;
  20 class nsSliderFrame;
  21
  22 namespace mozilla {
  23 class nsDisplaySliderMarks;
  24 class PresShell;
  25 }  // namespace mozilla
  26
  27 nsIFrame* NS_NewSliderFrame(mozilla::PresShell* aPresShell,
  28                             mozilla::ComputedStyle* aStyle);
  29
  30 class nsSliderMediator final : public nsIDOMEventListener {
  31  public:
  32   NS_DECL_ISUPPORTS
  33
  34   nsSliderFrame* mSlider;
  35
  36   explicit nsSliderMediator(nsSliderFrame* aSlider) { mSlider = aSlider; }
  37
  38   void SetSlider(nsSliderFrame* aSlider) { mSlider = aSlider; }
  39
  40   NS_DECL_NSIDOMEVENTLISTENER
  41
  42  protected:
  43   virtual ~nsSliderMediator() = default;
  44 };
  45
  46 class nsSliderFrame final : public nsContainerFrame {
  47  public:
  48   NS_DECL_FRAMEARENA_HELPERS(nsSliderFrame)
  49   NS_DECL_QUERYFRAME
  50
  51   friend class nsSliderMediator;
  52   friend class mozilla::nsDisplaySliderMarks;
  53
  54   explicit nsSliderFrame(ComputedStyle* aStyle, nsPresContext* aPresContext);
  55   virtual ~nsSliderFrame();
  56
  57   // Get the point associated with this event. Returns true if a single valid
  58   // point was found. Otherwise false.
  59   bool GetEventPoint(mozilla::WidgetGUIEvent* aEvent, nsPoint& aPoint);
  60   // Gets the event coordinates relative to the widget associated with this
  61   // frame. Return true if a single valid point was found.
  62   bool GetEventPoint(mozilla::WidgetGUIEvent* aEvent,
  63                      mozilla::LayoutDeviceIntPoint& aPoint);
  64
  65 #ifdef DEBUG_FRAME_DUMP
  66   nsresult GetFrameName(nsAString& aResult) const override {
  67     return MakeFrameName(u"SliderFrame"_ns, aResult);
  68   }
  69 #endif
  70
  71   void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
  72               const ReflowInput& aReflowInput,
  73               nsReflowStatus& aStatus) override;
  74
  75   // nsIFrame overrides
  76   void Destroy(DestroyContext&) override;
  77
  78   void BuildDisplayList(nsDisplayListBuilder* aBuilder,
  79                         const nsDisplayListSet& aLists) override;
  80
  81   void BuildDisplayListForThumb(nsDisplayListBuilder* aBuilder,
  82                                 nsIFrame* aThumb,
  83                                 const nsDisplayListSet& aLists);
  84
  85   nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
  86                             int32_t aModType) override;
  87
  88   void Init(nsIContent* aContent, nsContainerFrame* aParent,
  89             nsIFrame* aPrevInFlow) override;
  90
  91   nsresult HandleEvent(nsPresContext* aPresContext,
  92                        mozilla::WidgetGUIEvent* aEvent,
  93                        nsEventStatus* aEventStatus) override;
  94
  95   // nsContainerFrame overrides
  96   void SetInitialChildList(ChildListID aListID,
  97                            nsFrameList&& aChildList) override;
  98   void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override;
  99   void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
 100                     const nsLineList::iterator* aPrevFrameLine,
 101                     nsFrameList&& aFrameList) override;
 102   void RemoveFrame(DestroyContext&, ChildListID, nsIFrame*) override;
 103
 104   nsresult StartDrag(mozilla::dom::Event* aEvent);
 105   nsresult StopDrag();
 106
 107   void StartAPZDrag(mozilla::WidgetGUIEvent* aEvent);
 108
 109   static int32_t GetCurrentPosition(nsIContent* content);
 110   static int32_t GetMinPosition(nsIContent* content);
 111   static int32_t GetMaxPosition(nsIContent* content);
 112   static int32_t GetIncrement(nsIContent* content);
 113   static int32_t GetPageIncrement(nsIContent* content);
 114   static int32_t GetIntegerAttribute(nsIContent* content, nsAtom* atom,
 115                                      int32_t defaultValue);
 116
 117   NS_IMETHOD HandlePress(nsPresContext* aPresContext,
 118                          mozilla::WidgetGUIEvent* aEvent,
 119                          nsEventStatus* aEventStatus) override;
 120
 121   NS_IMETHOD HandleMultiplePress(nsPresContext* aPresContext,
 122                                  mozilla::WidgetGUIEvent* aEvent,
 123                                  nsEventStatus* aEventStatus,
 124                                  bool aControlHeld) override {
 125     return NS_OK;
 126   }
 127
 128   MOZ_CAN_RUN_SCRIPT
 129   NS_IMETHOD HandleDrag(nsPresContext* aPresContext,
 130                         mozilla::WidgetGUIEvent* aEvent,
 131                         nsEventStatus* aEventStatus) override {
 132     return NS_OK;
 133   }
 134
 135   NS_IMETHOD HandleRelease(nsPresContext* aPresContext,
 136                            mozilla::WidgetGUIEvent* aEvent,
 137                            nsEventStatus* aEventStatus) override;
 138
 139   // Return the ratio the scrollbar thumb should move in proportion to the
 140   // scrolled frame.
 141   float GetThumbRatio() const;
 142
 143   // Notify the slider frame that an async scrollbar drag was started on the
 144   // APZ side without consulting the main thread. The block id is the APZ
 145   // input block id of the mousedown that started the drag.
 146   void AsyncScrollbarDragInitiated(uint64_t aDragBlockId);
 147
 148   // Notify the slider frame that an async scrollbar drag requested in
 149   // StartAPZDrag() was rejected by APZ, and the slider frame should
 150   // fall back to main-thread dragging.
 151   void AsyncScrollbarDragRejected();
 152
 153   bool OnlySystemGroupDispatch(mozilla::EventMessage aMessage) const override;
 154
 155   // Returns the associated scrollframe that contains this slider if any.
 156   nsIScrollableFrame* GetScrollFrame();
 157
 158  private:
 159   bool GetScrollToClick();
 160   nsScrollbarFrame* Scrollbar();
 161   bool ShouldScrollForEvent(mozilla::WidgetGUIEvent* aEvent);
 162   bool ShouldScrollToClickForEvent(mozilla::WidgetGUIEvent* aEvent);
 163   bool IsEventOverThumb(mozilla::WidgetGUIEvent* aEvent);
 164
 165   void PageUpDown(nscoord change);
 166   void SetCurrentThumbPosition(nsIContent* aScrollbar, nscoord aNewPos,
 167                                bool aIsSmooth, bool aMaySnap);
 168   void SetCurrentPosition(nsIContent* aScrollbar, int32_t aNewPos,
 169                           bool aIsSmooth);
 170   void SetCurrentPositionInternal(nsIContent* aScrollbar, int32_t pos,
 171                                   bool aIsSmooth);
 172   void CurrentPositionChanged();
 173
 174   void DragThumb(bool aGrabMouseEvents);
 175   void AddListener();
 176   void RemoveListener();
 177   bool isDraggingThumb() const;
 178
 179   void SuppressDisplayport();
 180   void UnsuppressDisplayport();
 181
 182   void StartRepeat() {
 183     nsRepeatService::GetInstance()->Start(Notify, this, mContent->OwnerDoc(),
 184                                           "nsSliderFrame"_ns);
 185   }
 186   void StopRepeat() {
 187     nsRepeatService::GetInstance()->Stop(Notify, this);
 188     mCurrentClickHoldDestination = Nothing();
 189   }
 190   void Notify();
 191   static void Notify(void* aData) {
 192     (static_cast<nsSliderFrame*>(aData))->Notify();
 193   }
 194   void PageScroll(bool aClickAndHold);
 195
 196   nsPoint mDestinationPoint;
 197   // If we are in a scrollbar track click-and-hold, this is populated with
 198   // the destination of the scroll started at the most recent tick of the
 199   // repeat timer.
 200   Maybe<nsPoint> mCurrentClickHoldDestination;
 201   RefPtr<nsSliderMediator> mMediator;
 202
 203   float mRatio;
 204
 205   nscoord mDragStart;
 206   nscoord mThumbStart;
 207
 208   int32_t mCurPos;
 209
 210   nscoord mRepeatDirection;
 211
 212   bool mDragFinished;
 213
 214   // true if an attribute change has been caused by the user manipulating the
 215   // slider. This allows notifications to tell how a slider's current position
 216   // was changed.
 217   bool mUserChanged;
 218
 219   // true if we've handed off the scrolling to APZ. This means that we should
 220   // ignore scrolling events as the position will be updated by APZ. If we were
 221   // to process these events then the scroll position update would conflict
 222   // causing the scroll position to jump.
 223   bool mScrollingWithAPZ;
 224
 225   // true if displayport suppression is active, for more performant
 226   // scrollbar-dragging behaviour.
 227   bool mSuppressionActive;
 228
 229   // If APZ initiated a scrollbar drag without main-thread involvement, it
 230   // notifies us and this variable stores the input block id of the APZ input
 231   // block that started the drag. This lets us handle the corresponding
 232   // mousedown event properly, if it arrives after the scroll position has
 233   // been shifted due to async scrollbar drag.
 234   Maybe<uint64_t> mAPZDragInitiated;
 235
 236   nscoord mThumbMinLength;
 237
 238   static bool gMiddlePref;
 239 };  // class nsSliderFrame
 240
 241 #endif