Fix handler creation to happen on init (#11172)

Fix handler creation to happen on init

1 files changed, 28 insertions, 18 deletions

diff --git a/client/src/main/java/com/vaadin/client/connectors/grid/ComponentRendererConnector.java b/client/src/main/java/com/vaadin/client/connectors/grid/ComponentRendererConnector.java
index 649cec0b36..df8ace1a4e 100644
--- a/client/src/main/java/com/vaadin/client/connectors/grid/ComponentRendererConnector.java
+++ b/client/src/main/java/com/vaadin/client/connectors/grid/ComponentRendererConnector.java
@@ -25,6 +25,7 @@ import com.google.gwt.user.client.ui.SimplePanel;
 import com.google.gwt.user.client.ui.Widget;
 import com.vaadin.client.ComponentConnector;
 import com.vaadin.client.ConnectorMap;
+import com.vaadin.client.ServerConnector;
 import com.vaadin.client.renderers.Renderer;
 import com.vaadin.client.renderers.WidgetRenderer;
 import com.vaadin.client.ui.AbstractComponentConnector;
@@ -43,12 +44,18 @@ import com.vaadin.ui.renderers.ComponentRenderer;
  */
 @Connect(ComponentRenderer.class)
 public class ComponentRendererConnector
-    extends AbstractGridRendererConnector<String> {
+        extends AbstractGridRendererConnector<String> {
 
     private HashSet<String> knownConnectors = new HashSet<>();
     private HandlerRegistration handlerRegistration;
 
     @Override
+    public void setParent(ServerConnector parent) {
+        super.setParent(parent);
+        createConnectorHierarchyChangeHandler();
+    }
+
+    @Override
     protected Renderer<String> createRenderer() {
         return new WidgetRenderer<String, SimplePanel>() {
 
@@ -61,12 +68,12 @@ public class ComponentRendererConnector
 
             @Override
             public void render(RendererCellReference cell, String connectorId,
-                               SimplePanel widget) {
-                createConnectorHierarchyChangeHandler();
+                    SimplePanel widget) {
+                assert handlerRegistration != null : "HirarchyChangeHandler should not be null when rendering.";
                 Widget connectorWidget = null;
                 if (connectorId != null) {
                     ComponentConnector connector = (ComponentConnector) ConnectorMap
-                        .get(getConnection()).getConnector(connectorId);
+                            .get(getConnection()).getConnector(connectorId);
                     if (connector != null) {
                         connectorWidget = connector.getWidget();
                         knownConnectors.add(connectorId);
@@ -95,23 +102,26 @@ public class ComponentRendererConnector
 
     /**
      * Adds a listener for grid hierarchy changes to find detached connectors
-     * previously handled by this renderer in order to detach from DOM their widgets
-     * before {@link AbstractComponentConnector#onUnregister()} is invoked
-     * otherwise an error message is logged.
+     * previously handled by this renderer in order to detach from DOM their
+     * widgets before {@link AbstractComponentConnector#onUnregister()} is
+     * invoked otherwise an error message is logged.
      */
     private void createConnectorHierarchyChangeHandler() {
-        if (handlerRegistration == null) {
-            handlerRegistration = getGridConnector().addConnectorHierarchyChangeHandler(event -> {
-                Iterator<String> iterator = knownConnectors.iterator();
-                while (iterator.hasNext()) {
-                    ComponentConnector connector = (ComponentConnector) ConnectorMap.get(getConnection()).getConnector(iterator.next());
-                    if (connector != null && connector.getParent() == null) {
-                        connector.getWidget().removeFromParent();
-                        iterator.remove();
+        assert handlerRegistration == null : "Trying to re-initialize HierarchyChangeHandler";
+        handlerRegistration = getGridConnector()
+                .addConnectorHierarchyChangeHandler(event -> {
+                    Iterator<String> iterator = knownConnectors.iterator();
+                    while (iterator.hasNext()) {
+                        ComponentConnector connector = (ComponentConnector) ConnectorMap
+                                .get(getConnection())
+                                .getConnector(iterator.next());
+                        if (connector != null
+                                && connector.getParent() == null) {
+                            connector.getWidget().removeFromParent();
+                            iterator.remove();
+                        }
                     }
-                }
-            });
-        }
+                });
     }
 
     private void unregisterHierarchyHandler() {