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/*
* Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef PlatformScrollbar_h
#define PlatformScrollbar_h
#include <windows.h>
#include "Widget.h"
#include "ScrollBar.h"
#include "Timer.h"
namespace gfx {
class PlatformCanvas;
}
namespace WebCore {
// IMPORTANT NOTES ABOUT SCROLLBARS
//
// WebKit uses scrollbars in two ways. The first way is as a scroll control
// for a ScrollView. This scrollbar sits inside the ScrollView's rect and
// modifies its scrollOffset. Because it is inside the ScrollView's rect, it
// is a child of the ScrollView, but because it is not really part of the
// scrollView's content, it doesn't move as the scrollOffset changes.
//
// The second use is as a scroll control for things other than a ScrollView,
// e.g. a <select>. A <select> is not a ScrollView, so the scrollbar is not a
// child of it -- instead, it is a child of the ScrollView representing the
// frame in which the <select> (and the scrollbar) are located. In this case,
// the scrollbar IS part of the ScrollView's content, and it moves when the
// scrollOffset changes.
//
// ScrollViewWin distinguishes these two cases in its convertChildToSelf and
// convertSelfToChild methods, which are used when converting coordinates
// between the ScrollBar's coordinate system and that of the native window.
class PlatformScrollbar : public Widget, public Scrollbar {
public:
PlatformScrollbar(ScrollbarClient*, ScrollbarOrientation, ScrollbarControlSize);
virtual ~PlatformScrollbar();
virtual bool isWidget() const { return true; }
virtual int width() const;
virtual int height() const;
virtual void setRect(const IntRect&);
virtual void setEnabled(bool);
virtual bool isEnabled() const { return m_enabled; }
virtual void paint(GraphicsContext*, const IntRect& damageRect);
virtual void setFrameGeometry(const IntRect& rect);
// All mouse handler functions below receive mouse events in window
// coordinates.
// NOTE: These may be called after we've been removed from the widget/
// window hierarchy, for example because the EventHandler keeps a reference
// around and tries to feed us MouseOut events. In this case, doing
// something would be not only pointless but dangerous, as without a
// parent() we will end up failing an ASSERT(). So bail early if we get to
// any of these with no parent().
virtual bool handleMouseMoveEvent(const PlatformMouseEvent&);
virtual bool handleMouseOutEvent(const PlatformMouseEvent&);
virtual bool handleMousePressEvent(const PlatformMouseEvent&);
virtual bool handleMouseReleaseEvent(const PlatformMouseEvent&);
virtual IntRect windowClipRect() const;
static void themeChanged();
static int horizontalScrollbarHeight(ScrollbarControlSize size = RegularScrollbar);
static int verticalScrollbarWidth(ScrollbarControlSize size = RegularScrollbar);
// Scrolls the page when auto-repeat scrolling.
void autoscrollTimerFired(Timer<PlatformScrollbar>*);
// This function receives events in window coordinates.
void handleMouseMoveEventWhenCapturing(const PlatformMouseEvent& e);
protected:
virtual void updateThumbPosition();
virtual void updateThumbProportion();
private:
// Scroll bar segment identifiers
enum Segment {
Arrow1 = 0,
Track, // Only used when scrollbar does not contain a thumb
BeforeThumb, // -|
Thumb, // -+ Only used when scrollbar contains a thumb
AfterThumb, // -|
Arrow2,
None,
NumSegments = None
};
// Turns on/off whether we have mouse capture. This is only for tracking,
// as the EventHandler is what controls the actual capture.
void setCapturingMouse(bool capturing);
// Returns the girth of the scrollbar arrow button for layout, given the
// system metrics code for the desired direction's button and a limiting
// height (for vertical scroll bars) or width (for horizontal scrollbars).
// Also computes the background span (available remaining space).
int scrollButtonGirth(int systemMetricsCode, int limit,
int* backgroundSpan);
// Returns the girth of the scrollbar thumb for layout, given the system
// metrics code for the desired direction's thumb and the background span
// (space remaining after the buttons are drawn).
int scrollThumbGirth(int systemMetricsCode, int backgroundSpan);
// Computes the layout of the scroll bar given its current configuration.
void layout();
// Sets the current mouse position to the coordinates in |event|.
void updateMousePosition(int x, int y);
// Helper routine for updateMousePosition(), used to bypass layout().
void updateMousePositionInternal();
// Returns the correct state for the theme engine to draw a segment.
int getThemeState(Segment target) const;
int getThemeArrowState(Segment target) const;
int getClassicThemeState(Segment target) const;
// Draws the tick-marks on the scrollbar. The tick-marks are visual
// indicators showing the results from a find-in-page operation.
void DrawTickmarks(GraphicsContext* context) const;
IntPoint m_lastNativePos; // The last (native) mouse coordinate received.
struct {
int thumbPos; // Relevant (window) mouse coordinate, and...
int scrollVal; // ...current scrollvalue, when...
} m_dragOrigin; // ...user begins dragging the thumb.
RECT m_segmentRects[NumSegments];
// The native coordinates of the scrollbar
// segments.
Segment m_mouseOver; // The scrollbar segment the mouse is over.
Segment m_captureStart; // The segment on which we started capture.
Timer<PlatformScrollbar> m_autorepeatTimer;
// Timer to start and continue auto-repeat
// scrolling when the button is held down.
bool m_enabled; // True when the scrollbar is enabled.
bool m_needsLayout; // True when cached geometry may have changed
// Multipliers against scrollbar thickness that determine how far away from
// the scrollbar track the cursor can go before the thumb "snaps back"
static const int kOffSideMultiplier;
static const int kOffEndMultiplier;
// Auto-repeat delays, in seconds
static const double kAutorepeatInitialDelay;
static const double kAutorepeatRepeatInterval;
};
}
#endif // PlatformScrollbar_h
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