summaryrefslogtreecommitdiffstats
path: root/layout/xul/nsScrollbarFrame.h
blob: 4b48295f027e523397ebb93e00206ea2330567f5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */

//
// nsScrollbarFrame
//

#ifndef nsScrollbarFrame_h__
#define nsScrollbarFrame_h__

#include "mozilla/Attributes.h"
#include "mozilla/ScrollTypes.h"
#include "nsContainerFrame.h"
#include "nsIAnonymousContentCreator.h"

class nsIScrollbarMediator;

namespace mozilla {
class PresShell;
namespace dom {
class Element;
}
}  // namespace mozilla

nsIFrame* NS_NewScrollbarFrame(mozilla::PresShell* aPresShell,
                               mozilla::ComputedStyle* aStyle);

class nsScrollbarFrame final : public nsContainerFrame,
                               public nsIAnonymousContentCreator {
  using Element = mozilla::dom::Element;

 public:
  explicit nsScrollbarFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
      : nsContainerFrame(aStyle, aPresContext, kClassID),
        mSmoothScroll(false),
        mScrollUnit(mozilla::ScrollUnit::DEVICE_PIXELS),
        mDirection(0),
        mIncrement(0),
        mScrollbarMediator(nullptr),
        mUpTopButton(nullptr),
        mDownTopButton(nullptr),
        mSlider(nullptr),
        mThumb(nullptr),
        mUpBottomButton(nullptr),
        mDownBottomButton(nullptr) {}

  NS_DECL_QUERYFRAME
  NS_DECL_FRAMEARENA_HELPERS(nsScrollbarFrame)

#ifdef DEBUG_FRAME_DUMP
  nsresult GetFrameName(nsAString& aResult) const override {
    return MakeFrameName(u"ScrollbarFrame"_ns, aResult);
  }
#endif

  // nsIFrame overrides
  nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
                            int32_t aModType) override;

  NS_IMETHOD HandlePress(nsPresContext* aPresContext,
                         mozilla::WidgetGUIEvent* aEvent,
                         nsEventStatus* aEventStatus) override;

  NS_IMETHOD HandleMultiplePress(nsPresContext* aPresContext,
                                 mozilla::WidgetGUIEvent* aEvent,
                                 nsEventStatus* aEventStatus,
                                 bool aControlHeld) override;

  MOZ_CAN_RUN_SCRIPT
  NS_IMETHOD HandleDrag(nsPresContext* aPresContext,
                        mozilla::WidgetGUIEvent* aEvent,
                        nsEventStatus* aEventStatus) override;

  NS_IMETHOD HandleRelease(nsPresContext* aPresContext,
                           mozilla::WidgetGUIEvent* aEvent,
                           nsEventStatus* aEventStatus) override;

  mozilla::StyleScrollbarWidth ScrollbarWidth() const;
  nscoord ScrollbarTrackSize() const;
  nsSize ScrollbarMinSize() const;
  bool IsHorizontal() const;

  void Destroy(DestroyContext&) override;

  void Init(nsIContent* aContent, nsContainerFrame* aParent,
            nsIFrame* aPrevInFlow) override;

  void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
              const ReflowInput& aReflowInput,
              nsReflowStatus& aStatus) override;

  void SetScrollbarMediatorContent(nsIContent* aMediator);
  nsIScrollbarMediator* GetScrollbarMediator();

  /**
   * The following three methods set the value of mIncrement when a
   * scrollbar button is pressed.
   */
  void SetIncrementToLine(int32_t aDirection);
  void SetIncrementToPage(int32_t aDirection);
  void SetIncrementToWhole(int32_t aDirection);

  /**
   * If aImplementsScrollByUnit is Yes then this uses mSmoothScroll,
   * mScrollUnit, and mDirection and calls ScrollByUnit on the
   * nsIScrollbarMediator. The return value is 0. This is better because it is
   * more modern and the scroll frame can perform the scroll via apz for
   * example. The old way below is still supported for xul trees. If
   * aImplementsScrollByUnit is No this adds mIncrement to the current
   * position and updates the curpos attribute obeying mSmoothScroll.
   * @returns The new position after clamping, in CSS Pixels
   * @note This method might destroy the frame, pres shell, and other objects.
   */
  enum class ImplementsScrollByUnit { Yes, No };
  int32_t MoveToNewPosition(ImplementsScrollByUnit aImplementsScrollByUnit);
  int32_t GetIncrement() { return mIncrement; }

  // nsIAnonymousContentCreator
  nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) override;
  void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
                                uint32_t aFilter) override;

  void UpdateChildrenAttributeValue(nsAtom* aAttribute, bool aNotify);

 protected:
  bool mSmoothScroll;
  mozilla::ScrollUnit mScrollUnit;
  // Direction and multiple to scroll
  int32_t mDirection;

  // Amount to scroll, in CSSPixels
  // Ignored in favour of mScrollUnit/mDirection for regular scroll frames.
  // Trees use this though.
  int32_t mIncrement;

 private:
  nsCOMPtr<nsIContent> mScrollbarMediator;

  nsCOMPtr<Element> mUpTopButton;
  nsCOMPtr<Element> mDownTopButton;
  nsCOMPtr<Element> mSlider;
  nsCOMPtr<Element> mThumb;
  nsCOMPtr<Element> mUpBottomButton;
  nsCOMPtr<Element> mDownBottomButton;
};  // class nsScrollbarFrame

#endif