Browser compat for window.requestAnimationFrame

lib/dom/frog/dom_frog.dart

Index: lib/dom/frog/dom_frog.dart
diff --git a/lib/dom/frog/dom_frog.dart b/lib/dom/frog/dom_frog.dart
index 5be3f4c1695d81e1f871924db819733a4d7ab32f..2e909161f8ed1b08fa7fb04473b1da3b491ccdf6 100644
--- a/lib/dom/frog/dom_frog.dart
+++ b/lib/dom/frog/dom_frog.dart
@@ -1237,6 +1237,27 @@ class _DOMURLJs extends _DOMTypeJs implements DOMURL native "*DOMURL" {
 
 class _DOMWindowJs extends _EventTargetJs implements DOMWindow native "@*DOMWindow" {
 
+  Window get _top() native "return this.top;";
+
+  // Override top to return secure wrapper.
+  Window get top() => _DOMWindowCrossFrameImpl._createSafe(_top);
+
+  int requestAnimationFrame(RequestAnimationFrameCallback callback) native '''
+    if (!window.requestAnimationFrame) {
+      window.requestAnimationFrame =
+          window.webkitRequestAnimationFrame ||
+          window.mozRequestAnimationFrame ||
+          window.msRequestAnimationFrame ||
+          window.oRequestAnimationFrame ||
+          function (callback) { window.setTimeout(callback, 1000/60); };

[dgrove, 2012/04/21 04:47:49]

did you consider something more like
http://paulirish.com/2011/requestanimationframe-for-smart-animating/

[sra1, 2012/04/24 18:57:09]

tl;dr: yes.

This 'is' the first version at that page.
There is a long discussion of the 'clever' version at
https://gist.github.com/1579671
One commenter claimed the clever version was worse on iOS.
Another pointed out the behaviour is messed up if rAF is called twice.
We would have to measure and divine the correct behaviour if setTimeout is
actually being used.

+    }
+    return window.requestAnimationFrame(callback);
+''';
+
+  // Protect member 'requestAnimationFrame'.
+  _requestAnimationFrame() native 'requestAnimationFrame';
+
+
   static final int PERSISTENT = 1;
 
   static final int TEMPORARY = 0;
@@ -1423,11 +1444,6 @@ class _DOMWindowJs extends _EventTargetJs implements DOMWindow native "@*DOMWind
 
   void webkitResolveLocalFileSystemURL(String url, [EntryCallback successCallback = null, ErrorCallback errorCallback = null]) native;
 
-
-  Window get _top() native "return this.top;";
-
-  // Override top to return secure wrapper.
-  Window get top() => _DOMWindowCrossFrameImpl._createSafe(_top);
 }
 
 class _DataTransferItemJs extends _DOMTypeJs implements DataTransferItem native "*DataTransferItem" {