From b83240f9026489a241430e5d33ffbebdf93d14a5 Mon Sep 17 00:00:00 2001
From: Henri Sara <hesara@vaadin.com>
Date: Thu, 22 Aug 2013 11:28:39 +0300
Subject: [PATCH] Optimize CssLayout hierarchy update (#11284)

This change also adds some profiling for CssLayoutConnector.

Change-Id: Ia567c2c0ed2cff2c73a9019cea0f9a0240955dc7
---
 client/src/com/vaadin/client/ui/VCssLayout.java   |  3 +++
 .../client/ui/csslayout/CssLayoutConnector.java   | 15 ++++++++++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/client/src/com/vaadin/client/ui/VCssLayout.java b/client/src/com/vaadin/client/ui/VCssLayout.java
index 4357116707..c073c18ccb 100644
--- a/client/src/com/vaadin/client/ui/VCssLayout.java
+++ b/client/src/com/vaadin/client/ui/VCssLayout.java
@@ -40,7 +40,10 @@ public class VCssLayout extends FlowPanel {
 
     /**
      * For internal use only. May be removed or replaced in the future.
+     * 
+     * @deprecated since 7.1.4 no longer used by the framework, might be removed
      */
+    @Deprecated
     public void addOrMove(Widget child, int index) {
         Profiler.enter("VCssLayout.addOrMove");
         if (child.getParent() == this) {
diff --git a/client/src/com/vaadin/client/ui/csslayout/CssLayoutConnector.java b/client/src/com/vaadin/client/ui/csslayout/CssLayoutConnector.java
index 4c8d1a3ecc..b6dfffcc55 100644
--- a/client/src/com/vaadin/client/ui/csslayout/CssLayoutConnector.java
+++ b/client/src/com/vaadin/client/ui/csslayout/CssLayoutConnector.java
@@ -22,6 +22,7 @@ import com.vaadin.client.BrowserInfo;
 import com.vaadin.client.ComponentConnector;
 import com.vaadin.client.ConnectorHierarchyChangeEvent;
 import com.vaadin.client.FastStringMap;
+import com.vaadin.client.Profiler;
 import com.vaadin.client.Util;
 import com.vaadin.client.VCaption;
 import com.vaadin.client.communication.StateChangeEvent;
@@ -120,17 +121,23 @@ public class CssLayoutConnector extends AbstractLayoutConnector {
      */
     @Override
     public void onConnectorHierarchyChange(ConnectorHierarchyChangeEvent event) {
-        int index = 0;
+        Profiler.enter("CssLayoutConnector.onConnectorHierarchyChange");
+        Profiler.enter("CssLayoutConnector.onConnectorHierarchyChange add children");
+        // for large layouts, significantly faster to clear the list and always
+        // append to the end than to move the children around
+        getWidget().clear();
         for (ComponentConnector child : getChildComponents()) {
             VCaption childCaption = childIdToCaption
                     .get(child.getConnectorId());
             if (childCaption != null) {
-                getWidget().addOrMove(childCaption, index++);
+                getWidget().add(childCaption);
             }
-            getWidget().addOrMove(child.getWidget(), index++);
+            getWidget().add(child.getWidget());
         }
+        Profiler.leave("CssLayoutConnector.onConnectorHierarchyChange add children");
 
         // Detach old child widgets and possibly their caption
+        Profiler.enter("CssLayoutConnector.onConnectorHierarchyChange remove old children");
         for (ComponentConnector child : event.getOldChildren()) {
             if (child.getParent() == this) {
                 // Skip current children
@@ -143,6 +150,8 @@ public class CssLayoutConnector extends AbstractLayoutConnector {
                 getWidget().remove(vCaption);
             }
         }
+        Profiler.leave("CssLayoutConnector.onConnectorHierarchyChange remove old children");
+        Profiler.leave("CssLayoutConnector.onConnectorHierarchyChange");
     }
 
     /**
-- 
2.39.5