Mac: Optimize toolbar/bookmark drawing during live resize

chrome/browser/ui/cocoa/tabs/tab_strip_view.mm

 // Copyright (c) 2012 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/tabs/tab_strip_view.h"
 
 #include <cmath>  // floor
 
 #include "base/logging.h"
 #include "chrome/browser/themes/theme_service.h"
@@ skipping 27 matching lines @@
     lastMouseUp_ = -1000.0;
 
     // Register to be an URL drop target.
     dropHandler_.reset([[URLDropTargetHandler alloc] initWithView:self]);
 
     [self setWantsLayer:YES];
   }
   return self;
 }
 
+- (void)dealloc {
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [super dealloc];
+}
+
+- (void)viewWillMoveToWindow:(NSWindow*)window {
+  [super viewWillMoveToWindow:window];
+
+  if ([self window]) {
+    [[NSNotificationCenter defaultCenter]
+        removeObserver:self
+                  name:NSWindowDidBecomeMainNotification
+                object:[self window]];
+    [[NSNotificationCenter defaultCenter]
+        removeObserver:self
+                  name:NSWindowDidResignMainNotification
+                object:[self window]];
+  }
+  if (window) {
+    [[NSNotificationCenter defaultCenter]
+        addObserver:self
+           selector:@selector(windowFocusDidChange:)
+               name:NSWindowDidBecomeMainNotification
+             object:window];
+    [[NSNotificationCenter defaultCenter]
+        addObserver:self
+           selector:@selector(windowFocusDidChange:)
+               name:NSWindowDidResignMainNotification
+             object:window];
+  }
+}
+
+- (void)windowFocusDidChange:(NSNotification*)notification {
+  [self setNeedsDisplay:YES];
+}
+
 // Draw bottom border bitmap. Each tab is responsible for mimicking this bottom
 // border, unless it's the selected tab.
 - (void)drawBorder:(NSRect)dirtyRect {
   ThemeService* themeProvider =
       static_cast<ThemeService*>([[self window] themeProvider]);
   if (!themeProvider)
     return;
 
   // First draw the toolbar bitmap, so that theme colors can shine through.
   CGFloat backgroundHeight = 2 * [self cr_lineWidth];
   if (NSMinY(dirtyRect) < backgroundHeight) {
     gfx::ScopedNSGraphicsContextSaveGState scopedGState;
     NSGraphicsContext *context = [NSGraphicsContext currentContext];
     NSPoint position = [[self window] themeImagePositionForAlignment:
         THEME_IMAGE_ALIGN_WITH_TAB_STRIP];
     [context cr_setPatternPhase:position forView:self];
 
     // Themes don't have an inactive image so only look for one if there's no
     // theme.
-    bool active = [[self window] isKeyWindow] || [[self window] isMainWindow] ||
+    bool active = [[self window] isMainWindow] ||

[Andre, 2015/01/31 01:00:48]

A utility window can be key without being main, but I don't think a browser
window can be.

[Robert Sesek, 2015/02/02 19:32:16]

What about with child windows?

[Andre, 2015/02/02 21:40:08]

I tested that the browser window stays main when showing a bubble or a sheet.

                   !themeProvider->UsingDefaultTheme();
     int resource_id = active ? IDR_THEME_TOOLBAR : IDR_THEME_TOOLBAR_INACTIVE;
     [themeProvider->GetNSImageColorNamed(resource_id) set];
     NSRectFill(
         NSMakeRect(NSMinX(dirtyRect), 0, NSWidth(dirtyRect), backgroundHeight));
   }
 
   // Draw the border bitmap, which is partially transparent.
   NSImage* image = themeProvider->GetNSImageNamed(IDR_TOOLBAR_SHADE_TOP);
   if (NSMinY(dirtyRect) >= [image size].height)
     return;
 
   NSRect borderRect = dirtyRect;
   borderRect.size.height = [image size].height;
   borderRect.origin.y = 0;
 
-  BOOL focused = [[self window] isKeyWindow] || [[self window] isMainWindow];
+  BOOL focused = [[self window] isMainWindow];
   NSDrawThreePartImage(borderRect, nil, image, nil, /*vertical=*/ NO,
                        NSCompositeSourceOver,
                        focused ?  1.0 : tabs::kImageNoFocusAlpha,
                        /*flipped=*/ NO);
 }
 
 - (void)drawRect:(NSRect)rect {
   NSRect boundsRect = [self bounds];
 
   [self drawBorder:boundsRect];
@@ skipping 195 matching lines @@
 
 - (void)setNewTabButton:(NewTabButton*)button {
   newTabButton_.reset([button retain]);
 }
 
 - (void)setController:(TabStripController*)controller {
   controller_ = controller;
 }
 
 @end