Make tabOverlap dynamic depending on the number of non-mini tabs presented on...

chrome/browser/cocoa/tab_strip_controller.mm

Index: chrome/browser/cocoa/tab_strip_controller.mm
===================================================================
--- chrome/browser/cocoa/tab_strip_controller.mm	(revision 57038)
+++ chrome/browser/cocoa/tab_strip_controller.mm	(working copy)
@@ -68,6 +68,9 @@
 // incognito badge is present.
 const CGFloat kIncognitoBadgeTabStripShrink = 18;
 
+// The minimum offset of the tab over another tab
+const CGFloat minTabOffset = 2.0;
+
 // Time (in seconds) in which tabs animate to their final position.
 const NSTimeInterval kAnimationDuration = 0.125;
 
@@ -597,6 +600,13 @@
     tabStripModel_->SelectTabContentsAt(index, true);
 }
 
+- (NSView*)selectedTabView {
+	int selectedIndex = tabStripModel_->selected_index();
+	// Take closing tabs into account. They can't ever be selected.
+	selectedIndex = [self indexFromModelIndex:selectedIndex];
+	return [self viewAtIndex:selectedIndex];
+}
+
 // Called when the user closes a tab. Asks the model to close the tab. |sender|
 // is the TabView that is potentially going away.
 - (void)closeTab:(id)sender {
@@ -694,10 +704,11 @@
     return;
 
   const CGFloat kMaxTabWidth = [TabController maxTabWidth];
-  const CGFloat kMinTabWidth = [TabController minTabWidth];
+  const CGFloat kMinTabWidth = [TabController miniTabWidth];
   const CGFloat kMinSelectedTabWidth = [TabController minSelectedTabWidth];
   const CGFloat kMiniTabWidth = [TabController miniTabWidth];
   const CGFloat kAppTabWidth = [TabController appTabWidth];
+  const CGFloat kHovTabWidth = [TabController maxTabWidth] / 2;
 
   NSRect enclosingRect = NSZeroRect;
   ScopedNSAnimationContextGroup mainAnimationGroup(animate);
@@ -739,17 +750,29 @@
   // Initialize |nonMiniTabWidth| in case there aren't any non-mini-tabs; this
   // value shouldn't actually be used.
   CGFloat nonMiniTabWidth = kMaxTabWidth;
+  CGFloat availableSpaceForNewOverlap = availableSpaceForNonMini;
+  CGFloat tabOverlap = kTabOverlap;
   const NSInteger numberOfOpenNonMiniTabs = [self numberOfOpenNonMiniTabs];
   if (!verticalLayout_ && numberOfOpenNonMiniTabs) {
     // Find the width of a non-mini-tab. This only applies to horizontal
     // mode. Add in the amount we "get back" from the tabs overlapping.
+
     availableSpaceForNonMini += (numberOfOpenNonMiniTabs - 1) * kTabOverlap;
 
     // Divide up the space between the non-mini-tabs.
     nonMiniTabWidth = availableSpaceForNonMini / numberOfOpenNonMiniTabs;
 
+
+	// This is one of the approach to solve the tab overflow problem.
+	// Find new tab overlap for all non-mini-tab
+  CGFloat extraSpace = kMinTabWidth * numberOfOpenNonMiniTabs - availableSpaceForNewOverlap;
+	if (nonMiniTabWidth < kMinTabWidth) {
+		tabOverlap = MIN(kMiniTabWidth - minTabOffset,
+			extraSpace / (numberOfOpenNonMiniTabs - 1));
+	}
+
     // Clamp the width between the max and min.
-    nonMiniTabWidth = MAX(MIN(nonMiniTabWidth, kMaxTabWidth), kMinTabWidth);
+	nonMiniTabWidth = MAX(MIN(nonMiniTabWidth, kMaxTabWidth), kMinTabWidth);
   }
 
   BOOL visible = [[tabStripView_ window] isVisible];
@@ -816,7 +839,7 @@
         if (NSMidX(tabFrame) > placeholderMin) {
           hasPlaceholderGap = true;
           offset += NSWidth(placeholderFrame_);
-          offset -= kTabOverlap;
+          offset -= tabOverlap;
           tabFrame.origin.x = offset;
         }
       }
@@ -826,9 +849,13 @@
     // small and thus we enforce a different minimum width.
     tabFrame.size.width = [tab mini] ?
         ([tab app] ? kAppTabWidth : kMiniTabWidth) : nonMiniTabWidth;
-    if ([tab selected])
-      tabFrame.size.width = MAX(tabFrame.size.width, kMinSelectedTabWidth);
 
+	// Added width for hovered tab
+	tabFrame.size.width = [tab selected] ?
+		MAX(tabFrame.size.width, kMinSelectedTabWidth) :
+			([tab hovered] && ![tab mini] && ![tab app] ?
+				MAX(tabFrame.size.width, kHovTabWidth) : tabFrame.size.width);
+
     // Animate a new tab in by putting it below the horizon unless told to put
     // it in a specific location (i.e., from a drop).
     // TODO(pinkerton): figure out vertical tab animations.
@@ -858,7 +885,7 @@
       offset += NSHeight(tabFrame);
     } else {
       offset += NSWidth(tabFrame);
-      offset -= kTabOverlap;
+	  offset -= [tab mini] || [tab app] ? kTabOverlap : tabOverlap;
     }
     i++;
   }
@@ -873,7 +900,7 @@
     // We've already ensured there's enough space for the new tab button
     // so we don't have to check it against the available space. We do need
     // to make sure we put it after any placeholder.
-    newTabNewFrame.origin = NSMakePoint(offset, 0);
+    newTabNewFrame.origin = NSMakePoint(offset + (tabOverlap - kTabOverlap) + kNewTabButtonOffset, 0);
     newTabNewFrame.origin.x = MAX(newTabNewFrame.origin.x,
                                   NSMaxX(placeholderFrame_)) +
                                       kNewTabButtonOffset;
@@ -1339,13 +1366,6 @@
   [view setFrame:frame];
 }
 
-- (NSView*)selectedTabView {
-  int selectedIndex = tabStripModel_->selected_index();
-  // Take closing tabs into account. They can't ever be selected.
-  selectedIndex = [self indexFromModelIndex:selectedIndex];
-  return [self viewAtIndex:selectedIndex];
-}
-
 // Find the model index based on the x coordinate of the placeholder. If there
 // is no placeholder, this returns the end of the tab strip. Closing tabs are
 // not considered in computing the index.
@@ -1474,7 +1494,8 @@
   if (hoveredTab_ != tabView) {
     [hoveredTab_ mouseExited:nil];  // We don't pass event because moved events
     [tabView mouseEntered:nil];  // don't have valid tracking areas
-    hoveredTab_ = tabView;
+	hoveredTab_ = tabView;
+    [self layoutTabsWithAnimation:YES regenerateSubviews:NO];
   } else {
     [hoveredTab_ mouseMoved:event];
   }
@@ -1486,6 +1507,12 @@
     mouseInside_ = YES;
     [self setTabTrackingAreasEnabled:YES];
     [self mouseMoved:event];
+
+
+	  NSView* targetView = [tabStripView_ hitTest:[event locationInWindow]];
+	  if ([targetView isKindOfClass:[TabView class]]) {
+	    [self layoutTabsWithAnimation:YES regenerateSubviews:NO];
+	  }
   }
 }