scrollbarthememac.mm

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 2008 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 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 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. 
 */

#include "config.h"
#include "ScrollbarThemeMac.h"

#include "GraphicsContext.h"
#include "ImageBuffer.h"
#include "IntRect.h"
#include "Page.h"
#include "PlatformMouseEvent.h"
#include "Scrollbar.h"
#include "ScrollbarClient.h"
#include "Settings.h"
#include <Carbon/Carbon.h>
#include <wtf/StdLibExtras.h>
#include <wtf/UnusedParam.h>

// FIXME: There are repainting problems due to Aqua scroll bar buttons' visual overflow.

using namespace std;
using namespace WebCore;

static HashSet<Scrollbar*>* gScrollbars;

@interface ScrollbarPrefsObserver : NSObject
{

}

+ (void)registerAsObserver;
+ (void)appearancePrefsChanged:(NSNotification*)theNotification;
+ (void)behaviorPrefsChanged:(NSNotification*)theNotification;

@end

@implementation ScrollbarPrefsObserver

+ (void)appearancePrefsChanged:(NSNotification*)unusedNotification
{
    UNUSED_PARAM(unusedNotification);

    static_cast<ScrollbarThemeMac*>(ScrollbarTheme::nativeTheme())->preferencesChanged();
    if (!gScrollbars)
        return;
    HashSet<Scrollbar*>::iterator end = gScrollbars->end();
    for (HashSet<Scrollbar*>::iterator it = gScrollbars->begin(); it != end; ++it) {
        (*it)->styleChanged();
        (*it)->invalidate();
    }
}

+ (void)behaviorPrefsChanged:(NSNotification*)unusedNotification
{
    UNUSED_PARAM(unusedNotification);

    static_cast<ScrollbarThemeMac*>(ScrollbarTheme::nativeTheme())->preferencesChanged();
}

+ (void)registerAsObserver
{
    [[NSDistributedNotificationCenter defaultCenter] addObserver:self selector:@selector(appearancePrefsChanged:) name:@"AppleAquaScrollBarVariantChanged" object:nil suspensionBehavior:NSNotificationSuspensionBehaviorDeliverImmediately];
    [[NSDistributedNotificationCenter defaultCenter] addObserver:self selector:@selector(behaviorPrefsChanged:) name:@"AppleNoRedisplayAppearancePreferenceChanged" object:nil suspensionBehavior:NSNotificationSuspensionBehaviorCoalesce];
}

@end

namespace WebCore {

ScrollbarTheme* ScrollbarTheme::nativeTheme()
{
    DEFINE_STATIC_LOCAL(ScrollbarThemeMac, theme, ());
    return &theme;
}

// FIXME: Get these numbers from CoreUI.
static int cScrollbarThickness[] = { 15, 11 };
static int cRealButtonLength[] = { 28, 21 };
static int cButtonInset[] = { 14, 11 };
static int cButtonHitInset[] = { 3, 2 };
// cRealButtonLength - cButtonInset
static int cButtonLength[] = { 14, 10 };
static int cThumbMinLength[] = { 26, 20 };

static int cOuterButtonLength[] = { 16, 14 }; // The outer button in a double button pair is a bit bigger.
static int cOuterButtonOverlap = 2;

static float gInitialButtonDelay = 0.5f;
static float gAutoscrollButtonDelay = 0.05f;
static bool gJumpOnTrackClick = false;
static ScrollbarButtonsPlacement gButtonPlacement = ScrollbarButtonsDoubleEnd;

static void updateArrowPlacement()
{
    NSString *buttonPlacement = [[NSUserDefaults standardUserDefaults] objectForKey:@"AppleScrollBarVariant"];
    if ([buttonPlacement isEqualToString:@"Single"])
        gButtonPlacement = ScrollbarButtonsSingle;
    else if ([buttonPlacement isEqualToString:@"DoubleMin"])
        gButtonPlacement = ScrollbarButtonsDoubleStart;
    else if ([buttonPlacement isEqualToString:@"DoubleBoth"])
        gButtonPlacement = ScrollbarButtonsDoubleBoth;
    else
        gButtonPlacement = ScrollbarButtonsDoubleEnd; // The default is ScrollbarButtonsDoubleEnd.
}

void ScrollbarThemeMac::registerScrollbar(Scrollbar* scrollbar)
{
    if (!gScrollbars)
        gScrollbars = new HashSet<Scrollbar*>;
    gScrollbars->add(scrollbar);
}

void ScrollbarThemeMac::unregisterScrollbar(Scrollbar* scrollbar)
{
    gScrollbars->remove(scrollbar);
    if (gScrollbars->isEmpty()) {
        delete gScrollbars;
        gScrollbars = 0;
    }
}

ScrollbarThemeMac::ScrollbarThemeMac()
{
    static bool initialized;
    if (!initialized) {
        initialized = true;
        [ScrollbarPrefsObserver registerAsObserver];
        preferencesChanged();
    }
}

ScrollbarThemeMac::~ScrollbarThemeMac()
{
}

void ScrollbarThemeMac::preferencesChanged()
{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults synchronize];
    updateArrowPlacement();
    gInitialButtonDelay = [defaults floatForKey:@"NSScrollerButtonDelay"];
    gAutoscrollButtonDelay = [defaults floatForKey:@"NSScrollerButtonPeriod"];
    gJumpOnTrackClick = [defaults boolForKey:@"AppleScrollerPagingBehavior"];
}

int ScrollbarThemeMac::scrollbarThickness(ScrollbarControlSize controlSize)
{
    return cScrollbarThickness[controlSize];
}

double ScrollbarThemeMac::initialAutoscrollTimerDelay()
{
    return gInitialButtonDelay;
}

double ScrollbarThemeMac::autoscrollTimerDelay()
{
    return gAutoscrollButtonDelay;
}
    
ScrollbarButtonsPlacement ScrollbarThemeMac::buttonsPlacement() const
{
    return gButtonPlacement;
}

bool ScrollbarThemeMac::hasButtons(Scrollbar* scrollbar)
{
    return scrollbar->enabled() && (scrollbar->orientation() == HorizontalScrollbar ? 
             scrollbar->width() : 
             scrollbar->height()) >= 2 * (cRealButtonLength[scrollbar->controlSize()] - cButtonHitInset[scrollbar->controlSize()]);
}

bool ScrollbarThemeMac::hasThumb(Scrollbar* scrollbar)
{
    return scrollbar->enabled() && (scrollbar->orientation() == HorizontalScrollbar ? 
             scrollbar->width() : 
             scrollbar->height()) >= 2 * cButtonInset[scrollbar->controlSize()] + cThumbMinLength[scrollbar->controlSize()] + 1;
}

static IntRect buttonRepaintRect(const IntRect& buttonRect, ScrollbarOrientation orientation, ScrollbarControlSize controlSize, bool start)
{
    IntRect paintRect(buttonRect);
    if (orientation == HorizontalScrollbar) {