Fixed position elements are misplaced when a WK1 view has contentInsets set

dethbakin · dethbakin · commit b56595c8b921 · 2014-07-18T22:24:36.000Z
https://bugs.webkit.org/show_bug.cgi?id=135031 -and corresponding- <rdar://problem/17682335> Reviewed by Tim Horton. [NSScrollView documentVisibleRect] includes content that is within the inset-area of a view, but WebCore is interested in the content that is fully visible, so we need to factor the inset sizes out of this rect. Implement contract() to avoid the awkwardness of calling expand() with negative values. * platform/graphics/IntSize.h: (WebCore::IntSize::contract): Factor out insets * platform/mac/ScrollViewMac.mm: (WebCore::ScrollView::platformVisibleContentRect): (WebCore::ScrollView::platformVisibleContentSize): Canonical link: https://commits.webkit.org/152977@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@171246 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
@@ -1,3 +1,26 @@
+2014-07-18  Beth Dakin  <bdakin@apple.com>
+
+        Fixed position elements are misplaced when a WK1 view has contentInsets set
+        https://bugs.webkit.org/show_bug.cgi?id=135031
+        -and corresponding-
+        <rdar://problem/17682335>
+
+        Reviewed by Tim Horton.
+
+        [NSScrollView documentVisibleRect] includes content that is within the inset-area 
+        of a view, but WebCore is interested in the content that is fully visible, so we 
+        need to factor the inset sizes out of this rect.
+
+        Implement contract() to avoid the awkwardness of calling expand() with negative 
+        values.
+        * platform/graphics/IntSize.h:
+        (WebCore::IntSize::contract):
+
+        Factor out insets
+        * platform/mac/ScrollViewMac.mm:
+        (WebCore::ScrollView::platformVisibleContentRect):
+        (WebCore::ScrollView::platformVisibleContentSize):
+
 2014-07-18  Tim Horton  <timothy_horton@apple.com>
 
         Take navigation snapshots whenever the current back-forward item is going to change
diff --git a/Source/WebCore/platform/graphics/IntSize.h b/Source/WebCore/platform/graphics/IntSize.h
@@ -81,6 +81,12 @@ class IntSize {
         m_height += height;
     }
 
+    void contract(int width, int height)
+    {
+        m_width -= width;
+        m_height -= height;
+    }
+
     void scale(float widthScale, float heightScale)
     {
         m_width = static_cast<int>(static_cast<float>(m_width) * widthScale);
diff --git a/Source/WebCore/platform/mac/ScrollViewMac.mm b/Source/WebCore/platform/mac/ScrollViewMac.mm
@@ -34,6 +34,10 @@
 #import "NotImplemented.h"
 #import "WebCoreFrameView.h"
 
+@interface NSScrollView (Details)
+- (NSEdgeInsets)contentInsets;
+@end
+
 @interface NSWindow (WebWindowDetails)
 - (BOOL)_needsToResetDragMargins;
 - (void)_setNeedsToResetDragMargins:(BOOL)needs;
@@ -107,23 +111,30 @@ - (void)_setNeedsToResetDragMargins:(BOOL)needs;
 IntRect ScrollView::platformVisibleContentRect(bool includeScrollbars) const
 {
     BEGIN_BLOCK_OBJC_EXCEPTIONS;
-    IntRect result = enclosingIntRect([scrollView() documentVisibleRect]);
-    if (includeScrollbars)
-        result.setSize(IntSize([scrollView() frame].size));
-    return result;
+
+    IntRect visibleContentRect = enclosingIntRect([scrollView() documentVisibleRect]);
+#if __MAC_OS_X_VERSION_MIN_REQUIRED >= 10100
+    visibleContentRect.move(scrollView().contentInsets.left, scrollView().contentInsets.top);
+    visibleContentRect.contract(scrollView().contentInsets.left + scrollView().contentInsets.right, scrollView().contentInsets.top + scrollView().contentInsets.bottom);
+#endif
+
+    if (includeScrollbars) {
+        IntSize frameSize = IntSize([scrollView() frame].size);
+#if __MAC_OS_X_VERSION_MIN_REQUIRED >= 10100
+        frameSize.contract(scrollView().contentInsets.left + scrollView().contentInsets.right, scrollView().contentInsets.top + scrollView().contentInsets.bottom);
+#endif
+        visibleContentRect.setSize(frameSize);
+    }
+
+    return visibleContentRect;
     END_BLOCK_OBJC_EXCEPTIONS;
+
     return IntRect();
 }
 
 IntSize ScrollView::platformVisibleContentSize(bool includeScrollbars) const
 {
-    BEGIN_BLOCK_OBJC_EXCEPTIONS;
-    if (includeScrollbars)
-        return IntSize([scrollView() frame].size);
-
-    return expandedIntSize(FloatSize([scrollView() documentVisibleRect].size));
-    END_BLOCK_OBJC_EXCEPTIONS;
-    return IntSize();
+    return platformVisibleContentRect(includeScrollbars).size();
 }
 
 void ScrollView::platformSetContentsSize()

Original file line number	Diff line number	Diff line change
`@@ -81,6 +81,12 @@ class IntSize {`
`81`	`81`	`m_height += height;`
`82`	`82`	`}`
`83`	`83`
	`84`	`+ void contract(int width, int height)`
	`85`	`+ {`
	`86`	`+ m_width -= width;`
	`87`	`+ m_height -= height;`
	`88`	`+ }`
	`89`	`+`
`84`	`90`	`void scale(float widthScale, float heightScale)`
`85`	`91`	`{`
`86`	`92`	`m_width = static_cast<int>(static_cast<float>(m_width) * widthScale);`