The bookmark folder menus look bad when squeezed up against the bottom of a s...

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_controller.mm

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_controller.h"
 
 #include "base/mac/mac_util.h"
 #include "base/sys_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/bookmarks/bookmark_utils.h"
@@ skipping 440 matching lines @@
   }
   // Unhappy; do the best we can.
   return NSMaxX([[[self window] screen] frame]) - windowWidth;
 }
 
 
 // Compute and return the top left point of our window (screen
 // coordinates).  The top left is positioned in a manner similar to
 // cascading menus.  Windows may grow to either the right or left of
 // their parent (if a sub-folder) so we need to know |windowWidth|.
-- (NSPoint)windowTopLeftForWidth:(int)windowWidth {
+- (NSPoint)windowTopLeftForWidth:(int)windowWidth height:(int)windowHeight {
+  CGFloat kMinSqueezedMenuHeight = bookmarks::kBookmarkFolderButtonHeight * 2.0;
   NSPoint newWindowTopLeft;
   if (![parentController_ isKindOfClass:[self class]]) {
     // If we're not popping up from one of ourselves, we must be
     // popping up from the bookmark bar itself.  In this case, start
     // BELOW the parent button.  Our left is the button left; our top
     // is bottom of button's parent view.
     NSPoint buttonBottomLeftInScreen =
         [[parentButton_ window]
             convertBaseToScreen:[parentButton_
                                     convertPoint:NSZeroPoint toView:nil]];
     NSPoint bookmarkBarBottomLeftInScreen =
         [[parentButton_ window]
             convertBaseToScreen:[[parentButton_ superview]
                                     convertPoint:NSZeroPoint toView:nil]];
     newWindowTopLeft = NSMakePoint(
         buttonBottomLeftInScreen.x + bookmarks::kBookmarkBarButtonOffset,
         bookmarkBarBottomLeftInScreen.y + bookmarks::kBookmarkBarMenuOffset);
     // Make sure the window is on-screen; if not, push left.  It is
     // intentional that top level folders "push left" slightly
     // different than subfolders.
     NSRect screenFrame = [[[parentButton_ window] screen] frame];
     CGFloat spillOff = (newWindowTopLeft.x + windowWidth) - NSMaxX(screenFrame);
     if (spillOff > 0.0) {
       newWindowTopLeft.x = std::max(newWindowTopLeft.x - spillOff,
                                     NSMinX(screenFrame));
     }
+    // The menu looks bad when it is squeezed up against the bottom of the
+    // screen and ends up being only a few pixels tall. If it meets the
+    // threshold for this case, instead show the menu above the button.
+    NSRect visFrame = [[[parentButton_ window] screen] visibleFrame];
+    CGFloat availableVerticalSpace = newWindowTopLeft.y -
+        (NSMinY(visFrame) + bookmarks::kScrollWindowVerticalMargin);
+    if ((availableVerticalSpace < kMinSqueezedMenuHeight) &&
+        (windowHeight > availableVerticalSpace)) {
+      newWindowTopLeft.y = std::min(
+          newWindowTopLeft.y + windowHeight + NSHeight([parentButton_ frame]),
+          NSMaxY(visFrame));
+    }
   } else {
     // Parent is a folder: expose as much as we can vertically; grow right/left.
     newWindowTopLeft.x = [self childFolderWindowLeftForWidth:windowWidth];
     NSPoint topOfWindow = NSMakePoint(0,
                                       NSMaxY([parentButton_ frame]) -
                                           bookmarks::kBookmarkVerticalPadding);
     topOfWindow = [[parentButton_ window]
                    convertBaseToScreen:[[parentButton_ superview]
                                         convertPoint:topOfWindow toView:nil]];
     newWindowTopLeft.y = topOfWindow.y;
@@ skipping 197 matching lines @@
   // If the height has changed then also change the origin, and adjust the
   // scroll (if scrolling).
   if ([self canScrollUp]) {
     NSPoint scrollPoint = [scrollView_ documentVisibleRect].origin;
     scrollPoint.y += deltaMenuHeight;
     [[scrollView_ documentView] scrollPoint:scrollPoint];
   }
   folderFrame.size.height += deltaMenuHeight;
   [folderView_ setFrameSize:folderFrame.size];
   CGFloat windowWidth = [self adjustButtonWidths] + padding_;
-  NSPoint newWindowTopLeft = [self windowTopLeftForWidth:windowWidth];
+  NSPoint newWindowTopLeft = [self windowTopLeftForWidth:windowWidth
+                                                  height:deltaMenuHeight];
   CGFloat left = newWindowTopLeft.x;
   NSSize newSize = NSMakeSize(windowWidth, deltaMenuHeight);
   [self adjustWindowLeft:left size:newSize scrollingBy:0.0];
 }
 
 // Determine window size and position.
 // Create buttons for all our nodes.
 // TODO(jrg): break up into more and smaller routines for easier unit testing.
 - (void)configureWindow {
   const BookmarkNode* node = [parentButton_ bookmarkNode];
@@ skipping 39 matching lines @@
     }
   }
   [self layOutWindowWithHeight:height];
 }
 
 - (void)layOutWindowWithHeight:(CGFloat)height {
   // Lay out the window by adjusting all button widths to be consistent, then
   // base the window width on this ideal button width.
   CGFloat buttonWidth = [self adjustButtonWidths];
   CGFloat windowWidth = buttonWidth + padding_;
-  NSPoint newWindowTopLeft = [self windowTopLeftForWidth:windowWidth];
+  NSPoint newWindowTopLeft = [self windowTopLeftForWidth:windowWidth
+                                                  height:height];
   // Make sure as much of a submenu is exposed (which otherwise would be a
   // problem if the parent button is close to the bottom of the screen).
   if ([parentController_ isKindOfClass:[self class]]) {
     CGFloat minimumY = NSMinY([[[self window] screen] visibleFrame]) +
                        bookmarks::kScrollWindowVerticalMargin +
                        height;
     newWindowTopLeft.y = MAX(newWindowTopLeft.y, minimumY);
   }
   NSWindow* window = [self window];
   NSRect windowFrame = NSMakeRect(newWindowTopLeft.x,
@@ skipping 889 matching lines @@
 
 - (void)setIgnoreAnimations:(BOOL)ignore {
   ignoreAnimations_ = ignore;
 }
 
 - (BookmarkButton*)buttonThatMouseIsIn {
   return buttonThatMouseIsIn_;
 }
 
 @end  // BookmarkBarFolderController