[GTK] clicking on the scrollbar trough steps rather than jumps to the…

… clicked position https://bugs.webkit.org/show_bug.cgi?id=115363 Reviewed by Michael Catanzaro. Allow ScrollbarTheme to decide the behavior of a button press event, instead of only deciding whether to center on thumb or not. This way we can match the current GTK+ behavior in WebKit, without affecting other ports. * platform/ScrollTypes.h: Add ScrollbarButtonPressAction enum. * platform/Scrollbar.cpp: (WebCore::Scrollbar::mouseDown): Ask ScrollbarTheme to handle the event for the pressed part and do the requested action. * platform/ScrollbarTheme.cpp: (WebCore::ScrollbarTheme::handleMousePressEvent): Add default implementation. It's equivalent to the previous default implementation. * platform/ScrollbarTheme.h: * platform/gtk/ScrollbarThemeGtk.cpp: (WebCore::ScrollbarThemeGtk::handleMousePressEvent): Match current GTK+ behavior: left click centers on thumb and right click scrolls. Dragging the thumb works for left and middle buttons. * platform/gtk/ScrollbarThemeGtk.h: * platform/ios/ScrollbarThemeIOS.h: Remove shouldCenterOnThumb, and don't override handleMousePressEvent since iOS wants the default behavior. * platform/ios/ScrollbarThemeIOS.mm: * platform/mac/ScrollbarThemeMac.h: Override handleMousePressEvent and remove shouldCenterOnThumb. * platform/mac/ScrollbarThemeMac.mm: (WebCore::shouldCenterOnThumb): Same implementation just made it static to be used as helper. (WebCore::ScrollbarThemeMac::handleMousePressEvent): Return the desired action keeping the same behavior. * platform/win/ScrollbarThemeWin.cpp: (WebCore::ScrollbarThemeWin::handleMousePressEvent): Ditto. * platform/win/ScrollbarThemeWin.h: * rendering/RenderScrollbarTheme.h: Canonical link: https://commits.webkit.org/172396@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@196632 268f45cc-cd09-0410-ab3c-d52691b4dbfc
WebKit · Feb 16, 2016 · 0bd053218b1c67f7bf017c98adbbafcdea303da2 · 0bd0532
1 parent 161c8fb
commit 0bd053218b1c67f7bf017c98adbbafcdea303da2
Showing 14 changed files with 139 additions and 34 deletions.
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
@@ -1,3 +1,44 @@
+2016-02-16  Carlos Garcia Campos  <cgarcia@igalia.com>
+
+        [GTK] clicking on the scrollbar trough steps rather than jumps to the clicked position
+        https://bugs.webkit.org/show_bug.cgi?id=115363
+
+        Reviewed by Michael Catanzaro.
+
+        Allow ScrollbarTheme to decide the behavior of a button press event,
+        instead of only deciding whether to center on thumb or not. This
+        way we can match the current GTK+ behavior in WebKit, without
+        affecting other ports.
+
+        * platform/ScrollTypes.h: Add ScrollbarButtonPressAction enum.
+        * platform/Scrollbar.cpp:
+        (WebCore::Scrollbar::mouseDown): Ask ScrollbarTheme to handle the
+        event for the pressed part and do the requested action.
+        * platform/ScrollbarTheme.cpp:
+        (WebCore::ScrollbarTheme::handleMousePressEvent): Add default
+        implementation. It's equivalent to the previous default implementation.
+        * platform/ScrollbarTheme.h:
+        * platform/gtk/ScrollbarThemeGtk.cpp:
+        (WebCore::ScrollbarThemeGtk::handleMousePressEvent): Match current
+        GTK+ behavior: left click centers on thumb and right click
+        scrolls. Dragging the thumb works for left and middle buttons.
+        * platform/gtk/ScrollbarThemeGtk.h:
+        * platform/ios/ScrollbarThemeIOS.h: Remove shouldCenterOnThumb,
+        and don't override handleMousePressEvent since iOS wants the
+        default behavior.
+        * platform/ios/ScrollbarThemeIOS.mm:
+        * platform/mac/ScrollbarThemeMac.h: Override handleMousePressEvent
+        and remove shouldCenterOnThumb.
+        * platform/mac/ScrollbarThemeMac.mm:
+        (WebCore::shouldCenterOnThumb): Same implementation just made it
+        static to be used as helper.
+        (WebCore::ScrollbarThemeMac::handleMousePressEvent): Return the
+        desired action keeping the same behavior.
+        * platform/win/ScrollbarThemeWin.cpp:
+        (WebCore::ScrollbarThemeWin::handleMousePressEvent): Ditto.
+        * platform/win/ScrollbarThemeWin.h:
+        * rendering/RenderScrollbarTheme.h:
+
 2016-02-16  Carlos Garcia Campos  <cgarcia@igalia.com>
 
         Mouse cursor doesn't change when entering scrollbars

diff --git a/Source/WebCore/platform/ScrollTypes.h b/Source/WebCore/platform/ScrollTypes.h
@@ -180,6 +180,13 @@ enum ScrollBehaviorForFixedElements {
     StickToViewportBounds
 };
 
+enum class ScrollbarButtonPressAction {
+    None,
+    CenterOnThumb,
+    StartDrag,
+    Scroll
+};
+
 }
 
 #endif
diff --git a/Source/WebCore/platform/Scrollbar.cpp b/Source/WebCore/platform/Scrollbar.cpp
@@ -391,31 +391,34 @@ bool Scrollbar::mouseUp(const PlatformMouseEvent& mouseEvent)
 
 bool Scrollbar::mouseDown(const PlatformMouseEvent& evt)
 {
-    // Early exit for right click
-    if (evt.button() == RightButton)
-        return true; // FIXME: Handled as context menu by Qt right now.  Should just avoid even calling this method on a right click though.
+    ScrollbarPart pressedPart = theme().hitTest(*this, evt.position());
+    auto action = theme().handleMousePressEvent(*this, evt, pressedPart);
+    if (action == ScrollbarButtonPressAction::None)
+        return true;
 
     m_scrollableArea.mouseIsDownInScrollbar(this, true);
-    setPressedPart(theme().hitTest(*this, evt.position()));
-    int pressedPos = (orientation() == HorizontalScrollbar ? convertFromContainingWindow(evt.position()).x() : convertFromContainingWindow(evt.position()).y());
-
-    if ((m_pressedPart == BackTrackPart || m_pressedPart == ForwardTrackPart) && theme().shouldCenterOnThumb(*this, evt)) {
+    setPressedPart(pressedPart);
+
+    int pressedPosition = (orientation() == HorizontalScrollbar ? convertFromContainingWindow(evt.position()).x() : convertFromContainingWindow(evt.position()).y());
+    if (action == ScrollbarButtonPressAction::CenterOnThumb) {
         setHoveredPart(ThumbPart);
         setPressedPart(ThumbPart);
         m_dragOrigin = m_currentPos;
-        int thumbLen = theme().thumbLength(*this);
-        int desiredPos = pressedPos;
         // Set the pressed position to the middle of the thumb so that when we do the move, the delta
         // will be from the current pixel position of the thumb to the new desired position for the thumb.
-        m_pressedPos = theme().trackPosition(*this) + theme().thumbPosition(*this) + thumbLen / 2;
-        moveThumb(desiredPos);
+        m_pressedPos = theme().trackPosition(*this) + theme().thumbPosition(*this) + theme().thumbLength(*this) / 2;
+        moveThumb(pressedPosition);
         return true;
-    } else if (m_pressedPart == ThumbPart)
+    }
+
+    m_pressedPos = pressedPosition;
+
+    if (action == ScrollbarButtonPressAction::StartDrag)
         m_dragOrigin = m_currentPos;
-
-    m_pressedPos = pressedPos;
 
-    autoscrollPressedPart(theme().initialAutoscrollTimerDelay());
+    if (action == ScrollbarButtonPressAction::Scroll)
+        autoscrollPressedPart(theme().initialAutoscrollTimerDelay());
+
     return true;
 }
 

diff --git a/Source/WebCore/platform/ScrollbarTheme.cpp b/Source/WebCore/platform/ScrollbarTheme.cpp
@@ -26,6 +26,7 @@
 #include "config.h"
 #include "ScrollbarTheme.h"
 
+#include "PlatformMouseEvent.h"
 #include "ScrollbarThemeMock.h"
 #include "Settings.h"
 #include <wtf/NeverDestroyed.h>
@@ -41,4 +42,13 @@ ScrollbarTheme& ScrollbarTheme::theme()
     return nativeTheme();
 }
 
+ScrollbarButtonPressAction ScrollbarTheme::handleMousePressEvent(Scrollbar&, const PlatformMouseEvent& event, ScrollbarPart pressedPart)
+{
+    if (event.button() == RightButton)
+        return ScrollbarButtonPressAction::None;
+    if (pressedPart == ThumbPart)
+        return ScrollbarButtonPressAction::StartDrag;
+    return ScrollbarButtonPressAction::Scroll;
+}
+
 }
diff --git a/Source/WebCore/platform/ScrollbarTheme.h b/Source/WebCore/platform/ScrollbarTheme.h
@@ -95,7 +95,7 @@ class ScrollbarTheme {
     virtual void setUpContentShadowLayer(GraphicsLayer*) { }
 #endif
 
-    virtual bool shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&) { return false; }
+    virtual ScrollbarButtonPressAction handleMousePressEvent(Scrollbar&, const PlatformMouseEvent&, ScrollbarPart);
     virtual bool shouldSnapBackToDragOrigin(Scrollbar&, const PlatformMouseEvent&) { return false; }
     virtual bool shouldDragDocumentInsteadOfThumb(Scrollbar&, const PlatformMouseEvent&) { return false; }
     virtual int thumbPosition(Scrollbar&) { return 0; } // The position of the thumb relative to the track.

diff --git a/Source/WebCore/platform/gtk/ScrollbarThemeGtk.cpp b/Source/WebCore/platform/gtk/ScrollbarThemeGtk.cpp
@@ -493,9 +493,25 @@ bool ScrollbarThemeGtk::paint(Scrollbar& scrollbar, GraphicsContext& graphicsCon
     return true;
 }
 
-bool ScrollbarThemeGtk::shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent& event)
+ScrollbarButtonPressAction ScrollbarThemeGtk::handleMousePressEvent(Scrollbar&, const PlatformMouseEvent& event, ScrollbarPart pressedPart)
 {
-    return (event.shiftKey() && event.button() == LeftButton) || (event.button() == MiddleButton);
+    switch (pressedPart) {
+    case BackTrackPart:
+    case ForwardTrackPart:
+        if (event.button() == LeftButton)
+            return ScrollbarButtonPressAction::CenterOnThumb;
+        if (event.button() == RightButton)
+            return ScrollbarButtonPressAction::Scroll;
+        break;
+    case ThumbPart:
+        if (event.button() != RightButton)
+            return ScrollbarButtonPressAction::StartDrag;
+        break;
+    default:
+        break;
+    }
+
+    return ScrollbarButtonPressAction::None;
 }
 
 int ScrollbarThemeGtk::scrollbarThickness(ScrollbarControlSize)

diff --git a/Source/WebCore/platform/gtk/ScrollbarThemeGtk.h b/Source/WebCore/platform/gtk/ScrollbarThemeGtk.h
@@ -53,7 +53,7 @@ class ScrollbarThemeGtk final : public ScrollbarThemeComposite {
     virtual void paintTrackBackground(GraphicsContext&, Scrollbar&, const IntRect&) override;
     virtual void paintThumb(GraphicsContext&, Scrollbar&, const IntRect&) override;
     virtual void paintButton(GraphicsContext&, Scrollbar&, const IntRect&, ScrollbarPart) override;
-    virtual bool shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&) override;
+    virtual ScrollbarButtonPressAction handleMousePressEvent(Scrollbar&, const PlatformMouseEvent&, ScrollbarPart) override;
     virtual int scrollbarThickness(ScrollbarControlSize) override;
     virtual int minimumThumbLength(Scrollbar&) override;
 

diff --git a/Source/WebCore/platform/ios/ScrollbarThemeIOS.h b/Source/WebCore/platform/ios/ScrollbarThemeIOS.h
@@ -58,9 +58,7 @@ class ScrollbarThemeIOS : public ScrollbarThemeComposite {
     virtual IntRect trackRect(Scrollbar&, bool painting = false) override;
 
     virtual int minimumThumbLength(Scrollbar&) override;
-
-    virtual bool shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&) override;
-
+
 public:
     void preferencesChanged();
 };

diff --git a/Source/WebCore/platform/ios/ScrollbarThemeIOS.mm b/Source/WebCore/platform/ios/ScrollbarThemeIOS.mm
@@ -111,11 +111,6 @@
     return 0;
 }
 
-bool ScrollbarThemeIOS::shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&)
-{
-    return false;
-}
-
 bool ScrollbarThemeIOS::paint(Scrollbar&, GraphicsContext&, const IntRect& /*damageRect*/)
 {
     return true;

diff --git a/Source/WebCore/platform/mac/ScrollbarThemeMac.h b/Source/WebCore/platform/mac/ScrollbarThemeMac.h
@@ -84,7 +84,7 @@ class ScrollbarThemeMac : public ScrollbarThemeComposite {
 
     virtual int minimumThumbLength(Scrollbar&) override;
 
-    virtual bool shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&) override;
+    virtual ScrollbarButtonPressAction handleMousePressEvent(Scrollbar&, const PlatformMouseEvent&, ScrollbarPart) override;
     virtual bool shouldDragDocumentInsteadOfThumb(Scrollbar&, const PlatformMouseEvent&) override;
     int scrollbarPartToHIPressedState(ScrollbarPart);
 

diff --git a/Source/WebCore/platform/mac/ScrollbarThemeMac.mm b/Source/WebCore/platform/mac/ScrollbarThemeMac.mm
@@ -424,7 +424,7 @@ static IntRect buttonRepaintRect(const IntRect& buttonRect, ScrollbarOrientation
     END_BLOCK_OBJC_EXCEPTIONS;
 }
 
-bool ScrollbarThemeMac::shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent& evt)
+static bool shouldCenterOnThumb(const PlatformMouseEvent& evt)
 {
     if (evt.button() != LeftButton)
         return false;
@@ -433,6 +433,26 @@ static IntRect buttonRepaintRect(const IntRect& buttonRect, ScrollbarOrientation
     return evt.altKey();
 }
 
+ScrollbarButtonPressAction ScrollbarThemeMac::handleMousePressEvent(Scrollbar&, const PlatformMouseEvent& event, ScrollbarPart pressedPart)
+{
+    if (event.button() == RightButton)
+        return ScrollbarButtonPressAction::None;
+
+    switch (pressedPart) {
+    case BackTrackPart:
+    case ForwardTrackPart:
+        if (shouldCenterOnThumb(event))
+            return ScrollbarButtonPressAction::CenterOnThumb;
+        break;
+    case ThumbPart:
+        return ScrollbarButtonPressAction::StartDrag;
+    default:
+        break;
+    }
+
+    return ScrollbarButtonPressAction::Scroll;
+}
+
 bool ScrollbarThemeMac::shouldDragDocumentInsteadOfThumb(Scrollbar&, const PlatformMouseEvent& event)
 {
     return event.altKey();

diff --git a/Source/WebCore/platform/win/ScrollbarThemeWin.cpp b/Source/WebCore/platform/win/ScrollbarThemeWin.cpp
@@ -193,9 +193,24 @@ IntRect ScrollbarThemeWin::trackRect(Scrollbar& scrollbar, bool)
     return IntRect(scrollbar.x(), scrollbar.y() + thickness, thickness, scrollbar.height() - 2 * thickness);
 }
 
-bool ScrollbarThemeWin::shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent& evt)
+ScrollbarButtonPressAction ScrollbarThemeWin::handleMousePressEvent(Scrollbar&, const PlatformMouseEvent& event, ScrollbarPart pressedPart)
 {
-    return evt.shiftKey() && evt.button() == LeftButton;
+    if (event.button() == RightButton)
+        return ScrollbarButtonPressAction::None;
+
+    switch (pressedPart) {
+    case BackTrackPart:
+    case ForwardTrackPart:
+        if (event.shiftKey() && event.button() == LeftButton)
+            return ScrollbarButtonPressAction::CenterOnThumb;
+        break;
+    case ThumbPart:
+        return ScrollbarButtonPressAction::StartDrag;
+    default:
+        break;
+    }
+
+    return ScrollbarButtonPressAction::Scroll;
 }
 
 bool ScrollbarThemeWin::shouldSnapBackToDragOrigin(Scrollbar& scrollbar, const PlatformMouseEvent& evt)

diff --git a/Source/WebCore/platform/win/ScrollbarThemeWin.h b/Source/WebCore/platform/win/ScrollbarThemeWin.h
@@ -49,7 +49,7 @@ class ScrollbarThemeWin : public ScrollbarThemeComposite {
     bool hasButtons(Scrollbar&) override { return true; }
     bool hasThumb(Scrollbar&) override;
 
-    bool shouldCenterOnThumb(Scrollbar&, const PlatformMouseEvent&) override;
+    virtual ScrollbarButtonPressAction handleMousePressEvent(Scrollbar&, const PlatformMouseEvent&, ScrollbarPart) override;
     bool shouldSnapBackToDragOrigin(Scrollbar&, const PlatformMouseEvent&) override;
 
     void paintTrackBackground(GraphicsContext&, Scrollbar&, const IntRect&) override;

diff --git a/Source/WebCore/rendering/RenderScrollbarTheme.h b/Source/WebCore/rendering/RenderScrollbarTheme.h
@@ -46,8 +46,8 @@ class RenderScrollbarTheme final : public ScrollbarThemeComposite {
 
     virtual void paintScrollCorner(ScrollView*, GraphicsContext&, const IntRect& cornerRect) override;
 
-    virtual bool shouldCenterOnThumb(Scrollbar& scrollbar, const PlatformMouseEvent& event) override { return ScrollbarTheme::theme().shouldCenterOnThumb(scrollbar, event); }
-    
+    virtual ScrollbarButtonPressAction handleMousePressEvent(Scrollbar& scrollbar, const PlatformMouseEvent& event, ScrollbarPart pressedPart) override { return ScrollbarTheme::theme().handleMousePressEvent(scrollbar, event, pressedPart); }
+
     virtual double initialAutoscrollTimerDelay() override { return ScrollbarTheme::theme().initialAutoscrollTimerDelay(); }
     virtual double autoscrollTimerDelay() override { return ScrollbarTheme::theme().autoscrollTimerDelay(); }