Add a stack-based class for property disabling and re-enabling screen updating without epic fail. Fixes issues where we weren't re-enabling updates in many cases which caused both jank and resize issues.

BUG=13476
TEST=closing windows shouldn't have jank regardless of the # of tabs. Resizing a window shouldn't explode visually in the chrome.
Review URL: http://codereview.chromium.org/119363

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@17956 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 35 insertions, 0 deletions

diff --git a/base/scoped_nsdisable_screen_updates.h b/base/scoped_nsdisable_screen_updates.h
new file mode 100644
index 0000000..3258fca
--- /dev/null
+++ b/base/scoped_nsdisable_screen_updates.h
@@ -0,0 +1,35 @@
+// Copyright (c) 2009 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.
+
+#ifndef BASE_SCOPED_NSDISABLE_SCREEN_UPDATES_H_
+#define BASE_SCOPED_NSDISABLE_SCREEN_UPDATES_H_
+
+#import <Cocoa/Cocoa.h>
+
+#include "base/basictypes.h"
+
+namespace base {
+
+// A stack-based class to disable Cocoa screen updates. When instantiated, it
+// disables screen updates and enables them when destroyed. Update disabling
+// can be nested, and there is a time-maximum (about 1 second) after which
+// Cocoa will automatically re-enable updating. This class doesn't attempt to
+// overrule that.
+
+class ScopedNSDisableScreenUpdates {
+ public:
+  ScopedNSDisableScreenUpdates() {
+    NSDisableScreenUpdates();
+  }
+  ~ScopedNSDisableScreenUpdates() {
+    NSEnableScreenUpdates();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ScopedNSDisableScreenUpdates);
+};
+
+}  // namespace
+
+#endif