1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/generic/ScrollbarActivity.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,161 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef ScrollbarActivity_h___
1.10 +#define ScrollbarActivity_h___
1.11 +
1.12 +#include "mozilla/Attributes.h"
1.13 +#include "nsCOMPtr.h"
1.14 +#include "nsIDOMEventListener.h"
1.15 +#include "mozilla/TimeStamp.h"
1.16 +#include "nsRefreshDriver.h"
1.17 +
1.18 +class nsIContent;
1.19 +class nsIScrollbarOwner;
1.20 +class nsITimer;
1.21 +class nsIAtom;
1.22 +
1.23 +namespace mozilla {
1.24 +namespace layout {
1.25 +
1.26 +/**
1.27 + * ScrollbarActivity
1.28 + *
1.29 + * This class manages scrollbar behavior that imitates the native Mac OS X
1.30 + * Lion overlay scrollbar behavior: Scrollbars are only shown while "scrollbar
1.31 + * activity" occurs, and they're hidden with a fade animation after a short
1.32 + * delay.
1.33 + *
1.34 + * Scrollbar activity has these states:
1.35 + * - inactive:
1.36 + * Scrollbars are hidden.
1.37 + * - ongoing activity:
1.38 + * Scrollbars are visible and being operated on in some way, for example
1.39 + * because they're hovered or pressed.
1.40 + * - active, but waiting for fade out
1.41 + * Scrollbars are still completely visible but are about to fade away.
1.42 + * - fading out
1.43 + * Scrollbars are subject to a fade-out animation.
1.44 + *
1.45 + * Initial scrollbar activity needs to be reported by the scrollbar holder that
1.46 + * owns the ScrollbarActivity instance. This needs to happen via a call to
1.47 + * ActivityOccurred(), for example when the current scroll position or the size
1.48 + * of the scroll area changes.
1.49 + *
1.50 + * As soon as scrollbars are visible, the ScrollbarActivity class manages the
1.51 + * rest of the activity behavior: It ensures that mouse motions inside the
1.52 + * scroll area keep the scrollbars visible, and that scrollbars don't fade away
1.53 + * while they're being hovered / dragged. It also sets a sticky hover attribute
1.54 + * on the most recently hovered scrollbar.
1.55 + *
1.56 + * ScrollbarActivity falls into hibernation after the scrollbars have faded
1.57 + * out. It only starts acting after the next call to ActivityOccurred() /
1.58 + * ActivityStarted().
1.59 + */
1.60 +
1.61 +class ScrollbarActivity : public nsIDOMEventListener,
1.62 + public nsARefreshObserver {
1.63 +public:
1.64 + ScrollbarActivity(nsIScrollbarOwner* aScrollableFrame)
1.65 + : mScrollableFrame(aScrollableFrame)
1.66 + , mNestedActivityCounter(0)
1.67 + , mIsActive(false)
1.68 + , mIsFading(false)
1.69 + , mListeningForScrollbarEvents(false)
1.70 + , mListeningForScrollAreaEvents(false)
1.71 + , mHScrollbarHovered(false)
1.72 + , mVScrollbarHovered(false)
1.73 + , mDisplayOnMouseMove(false)
1.74 + , mScrollbarFadeBeginDelay(0)
1.75 + , mScrollbarFadeDuration(0)
1.76 + {
1.77 + QueryLookAndFeelVals();
1.78 + }
1.79 +
1.80 + NS_DECL_ISUPPORTS
1.81 + NS_DECL_NSIDOMEVENTLISTENER
1.82 +
1.83 + virtual ~ScrollbarActivity() {}
1.84 +
1.85 + void Destroy();
1.86 +
1.87 + void ActivityOccurred();
1.88 + void ActivityStarted();
1.89 + void ActivityStopped();
1.90 +
1.91 + virtual void WillRefresh(TimeStamp aTime) MOZ_OVERRIDE;
1.92 +
1.93 + static void FadeBeginTimerFired(nsITimer* aTimer, void* aSelf) {
1.94 + nsRefPtr<ScrollbarActivity> scrollbarActivity(
1.95 + reinterpret_cast<ScrollbarActivity*>(aSelf));
1.96 + scrollbarActivity->BeginFade();
1.97 + }
1.98 +
1.99 +protected:
1.100 +
1.101 + bool IsActivityOngoing()
1.102 + { return mNestedActivityCounter > 0; }
1.103 + bool IsStillFading(TimeStamp aTime);
1.104 + void QueryLookAndFeelVals();
1.105 +
1.106 + void HandleEventForScrollbar(const nsAString& aType,
1.107 + nsIContent* aTarget,
1.108 + nsIContent* aScrollbar,
1.109 + bool* aStoredHoverState);
1.110 +
1.111 + void SetIsActive(bool aNewActive);
1.112 + bool SetIsFading(bool aNewFading); // returns false if 'this' was destroyed
1.113 +
1.114 + void BeginFade();
1.115 + void EndFade();
1.116 +
1.117 + void StartFadeBeginTimer();
1.118 + void CancelFadeBeginTimer();
1.119 +
1.120 + void StartListeningForScrollbarEvents();
1.121 + void StartListeningForScrollAreaEvents();
1.122 + void StopListeningForScrollbarEvents();
1.123 + void StopListeningForScrollAreaEvents();
1.124 + void AddScrollbarEventListeners(nsIDOMEventTarget* aScrollbar);
1.125 + void RemoveScrollbarEventListeners(nsIDOMEventTarget* aScrollbar);
1.126 +
1.127 + void RegisterWithRefreshDriver();
1.128 + void UnregisterFromRefreshDriver();
1.129 +
1.130 + bool UpdateOpacity(TimeStamp aTime); // returns false if 'this' was destroyed
1.131 + void HoveredScrollbar(nsIContent* aScrollbar);
1.132 +
1.133 + nsRefreshDriver* GetRefreshDriver();
1.134 + nsIContent* GetScrollbarContent(bool aVertical);
1.135 + nsIContent* GetHorizontalScrollbar() { return GetScrollbarContent(false); }
1.136 + nsIContent* GetVerticalScrollbar() { return GetScrollbarContent(true); }
1.137 +
1.138 + const TimeDuration FadeDuration() {
1.139 + return TimeDuration::FromMilliseconds(mScrollbarFadeDuration);
1.140 + }
1.141 +
1.142 + nsIScrollbarOwner* mScrollableFrame;
1.143 + TimeStamp mFadeBeginTime;
1.144 + nsCOMPtr<nsITimer> mFadeBeginTimer;
1.145 + nsCOMPtr<nsIDOMEventTarget> mHorizontalScrollbar; // null while inactive
1.146 + nsCOMPtr<nsIDOMEventTarget> mVerticalScrollbar; // null while inactive
1.147 + int mNestedActivityCounter;
1.148 + bool mIsActive;
1.149 + bool mIsFading;
1.150 + bool mListeningForScrollbarEvents;
1.151 + bool mListeningForScrollAreaEvents;
1.152 + bool mHScrollbarHovered;
1.153 + bool mVScrollbarHovered;
1.154 +
1.155 + // LookAndFeel values we load on creation
1.156 + bool mDisplayOnMouseMove;
1.157 + int mScrollbarFadeBeginDelay;
1.158 + int mScrollbarFadeDuration;
1.159 +};
1.160 +
1.161 +} // namespace layout
1.162 +} // namespace mozilla
1.163 +
1.164 +#endif /* ScrollbarActivity_h___ */
