Example showing alternate async measurement solution

client/samples/total/src/SelectionManager.dart

Index: client/samples/total/src/SelectionManager.dart
diff --git a/client/samples/total/src/SelectionManager.dart b/client/samples/total/src/SelectionManager.dart
index ead003dec75bd5db4cc02905ff6b9f8a99bd8ee3..7a747d8a8df20d32bc07c3814290d7151348a687 100644
--- a/client/samples/total/src/SelectionManager.dart
+++ b/client/samples/total/src/SelectionManager.dart
@@ -1,4 +1,4 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
@@ -55,7 +55,7 @@ class SelectionManager {
     _selectionDiv = new Element.tag("div");
     _selectionDiv.id = "selection-${_spreadsheet.name}";
     _selectionDiv.attributes["class"] = "selection";
-    _selectionDiv.style.setProperty("display", "none");
+    _selectionDiv.style.display = "none";
     spreadsheetElement.nodes.add(_selectionDiv);
 
     Element thumb = new Element.tag("div");
@@ -95,14 +95,15 @@ class SelectionManager {
 
   // Hide the selection marquee and empty the selection range
   void clearSelection() {
-    _selectionDiv.style.setProperty("display", "none");
+    _selectionDiv.style.display = "none";
     _selectedCell = _selectionCorner = null;
     selectionChanged();
   }
 
   // Return a BoundingBox for the given CellRange, clipped to the visible region of the table
   // TODO:  deal with full row and/or column selection
-  Future<BoundingBox> getBoundingBoxForRange(CellRange r) {
+  BoundingBox getBoundingBoxForRange(CellRange r) {
+    assert(window.inMeasurementFrame);
     // Modify the overlay for entire row/column selection
     int minRow = r.minCorner.row;
     int maxRow = r.maxCorner.row;
@@ -151,21 +152,15 @@ class SelectionManager {
 
     // We need bounding box relative to the container which will be offset by
     // css.
-    final tableRect = _table.rect;
-    final minCellElmtRect = minCellElmt.rect;
-    final maxCellElmtRect = maxCellElmt.rect;
-
-    window.requestLayoutFrame(() {
-      ClientRect orgP = tableRect.value.bounding;
-      ClientRect minP = minCellElmtRect.value.bounding;
-      ClientRect maxP = maxCellElmtRect.value.bounding;
-      completer.complete(new BoundingBox(
-          (minP.left - orgP.left).toInt(),
-          (minP.top - orgP.top).toInt(),
-          (maxP.left - minP.left + maxCellElmtRect.value.client.width).toInt(),
-          (maxP.top - minP.top + maxCellElmtRect.value.client.height).toInt()));
-    });
-    return completer.future;
+
+    final orgP = _table.rect.bounding;
+    final minP = minCellElmt.rect.bounding;
+    final maxP = maxCellElmt.rect.bounding;
+    return new BoundingBox(
+        (minP.left - orgP.left).toInt(),
+        (minP.top - orgP.top).toInt(),
+        (maxP.left - minP.left + maxCellElmt.rect.client.width).toInt(),
+        (maxP.top - minP.top + maxCellElmt.rect.client.height).toInt());
   }
 
   CellRange getSelectionRange() => _getSelectionRange(_selectedCell, _selectionCorner);
@@ -227,16 +222,19 @@ class SelectionManager {
       return;
     }
 
-    getBoundingBoxForRange(r).then((BoundingBox box) {
-      if (box != null) {
-        _selectionDiv.style.setProperty("left", HtmlUtils.toPx(box.left));
-        _selectionDiv.style.setProperty("top", HtmlUtils.toPx(box.top));
-        _selectionDiv.style.setProperty("width", HtmlUtils.toPx(box.width));
-        _selectionDiv.style.setProperty("height", HtmlUtils.toPx(box.height));
-        _selectionDiv.style.removeProperty("display");
-      } else {
-        _selectionDiv.style.setProperty("display", "none");
-      }
+    window.requestMeasurementFrame(() {
+      final box = getBoundingBoxForRange(r);
+      return () {
+        if (box != null) {
+          _selectionDiv.style.left = HtmlUtils.toPx(box.left);
+          _selectionDiv.style.top = HtmlUtils.toPx(box.top);
+          _selectionDiv.style.width = HtmlUtils.toPx(box.width);
+          _selectionDiv.style.height = HtmlUtils.toPx(box.height);
+          _selectionDiv.style.removeProperty("display");
+        } else {
+          _selectionDiv.style.display = "none";
+        }
+      };
     });
   }