ScrollbarThemeChromiumLinux.cpp   [plain text]

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#include "config.h"
#include "ScrollbarThemeChromiumLinux.h"

#include "PlatformSupport.h"
#include "PlatformMouseEvent.h"
#include "Scrollbar.h"

namespace WebCore {

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

int ScrollbarThemeChromiumLinux::scrollbarThickness(ScrollbarControlSize controlSize)
{
    // Horiz and Vert scrollbars are the same thickness.
    IntSize scrollbarSize = PlatformSupport::getThemePartSize(PlatformSupport::PartScrollbarVerticalTrack);
    return scrollbarSize.width();
}

void ScrollbarThemeChromiumLinux::paintTrackPiece(GraphicsContext* gc, ScrollbarThemeClient* scrollbar, const IntRect& rect, ScrollbarPart partType)
{
    PlatformSupport::ThemePaintState state = scrollbar->hoveredPart() == partType ? PlatformSupport::StateHover : PlatformSupport::StateNormal;
    IntRect alignRect = trackRect(scrollbar, false);
    PlatformSupport::ThemePaintExtraParams extraParams;
    extraParams.scrollbarTrack.trackX = alignRect.x();
    extraParams.scrollbarTrack.trackY = alignRect.y();
    extraParams.scrollbarTrack.trackWidth = alignRect.width();
    extraParams.scrollbarTrack.trackHeight = alignRect.height();
    PlatformSupport::paintThemePart(
        gc,
        scrollbar->orientation() == HorizontalScrollbar ? PlatformSupport::PartScrollbarHorizontalTrack : PlatformSupport::PartScrollbarVerticalTrack,
        state,
        rect,
        &extraParams);
}

void ScrollbarThemeChromiumLinux::paintButton(GraphicsContext* gc, ScrollbarThemeClient* scrollbar, const IntRect& rect, ScrollbarPart part)
{
    PlatformSupport::ThemePart paintPart;
    PlatformSupport::ThemePaintState state = PlatformSupport::StateNormal;
    bool checkMin = false;
    bool checkMax = false;
    if (scrollbar->orientation() == HorizontalScrollbar) {
        if (part == BackButtonStartPart) {
            paintPart = PlatformSupport::PartScrollbarLeftArrow;
            checkMin = true;
        } else {
            paintPart = PlatformSupport::PartScrollbarRightArrow;
            checkMax = true;
        }
    } else {
        if (part == BackButtonStartPart) {
            paintPart = PlatformSupport::PartScrollbarUpArrow;
            checkMin = true;
        } else {
            paintPart = PlatformSupport::PartScrollbarDownArrow;
            checkMax = true;
        }
    }
    if ((checkMin && (scrollbar->currentPos() <= 0))
        || (checkMax && scrollbar->currentPos() == scrollbar->maximum())) {
        state = PlatformSupport::StateDisabled;
    } else {
        if (part == scrollbar->pressedPart())
            state = PlatformSupport::StatePressed;
        else if (part == scrollbar->hoveredPart())
            state = PlatformSupport::StateHover;
    }
    PlatformSupport::paintThemePart(gc, paintPart, state, rect, 0);
}

void ScrollbarThemeChromiumLinux::paintThumb(GraphicsContext* gc, ScrollbarThemeClient* scrollbar, const IntRect& rect)
{
    PlatformSupport::ThemePaintState state;

    if (scrollbar->pressedPart() == ThumbPart)
        state = PlatformSupport::StatePressed;
    else if (scrollbar->hoveredPart() == ThumbPart)
        state = PlatformSupport::StateHover;
    else
        state = PlatformSupport::StateNormal;
    PlatformSupport::paintThemePart(
        gc,
        scrollbar->orientation() == HorizontalScrollbar ? PlatformSupport::PartScrollbarHorizontalThumb : PlatformSupport::PartScrollbarVerticalThumb,
        state,
        rect,
        0);
}

bool ScrollbarThemeChromiumLinux::shouldCenterOnThumb(ScrollbarThemeClient*, const PlatformMouseEvent& evt)
{
    return (evt.shiftKey() && evt.button() == LeftButton) || (evt.button() == MiddleButton);
}

IntSize ScrollbarThemeChromiumLinux::buttonSize(ScrollbarThemeClient* scrollbar)
{
    if (scrollbar->orientation() == VerticalScrollbar) {
        IntSize size = PlatformSupport::getThemePartSize(PlatformSupport::PartScrollbarUpArrow);
        return IntSize(size.width(), scrollbar->height() < 2 * size.height() ? scrollbar->height() / 2 : size.height());
    }

    // HorizontalScrollbar
    IntSize size = PlatformSupport::getThemePartSize(PlatformSupport::PartScrollbarLeftArrow);
    return IntSize(scrollbar->width() < 2 * size.width() ? scrollbar->width() / 2 : size.width(), size.height());
}

int ScrollbarThemeChromiumLinux::minimumThumbLength(ScrollbarThemeClient* scrollbar)
{
    if (scrollbar->orientation() == VerticalScrollbar) {
        IntSize size = PlatformSupport::getThemePartSize(PlatformSupport::PartScrollbarVerticalThumb);
        return size.height();
    }

    IntSize size = PlatformSupport::getThemePartSize(PlatformSupport::PartScrollbarHorizontalThumb);
    return size.width();
}

} // namespace WebCore