Fix handling of hidden Components in Grid(#10367)

1 files changed, 59 insertions, 4 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 cc8647e58f..649cec0b36 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
@@ -15,12 +15,20 @@
  */
 package com.vaadin.client.connectors.grid;
 
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.logging.Logger;
+
 import com.google.gwt.core.client.GWT;
+import com.google.gwt.event.shared.HandlerRegistration;
 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.renderers.Renderer;
 import com.vaadin.client.renderers.WidgetRenderer;
+import com.vaadin.client.ui.AbstractComponentConnector;
+import com.vaadin.client.ui.AbstractConnector;
 import com.vaadin.client.widget.grid.RendererCellReference;
 import com.vaadin.shared.ui.Connect;
 import com.vaadin.shared.ui.grid.renderers.ComponentRendererState;
@@ -35,7 +43,10 @@ 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
     protected Renderer<String> createRenderer() {
@@ -50,13 +61,22 @@ public class ComponentRendererConnector
 
             @Override
             public void render(RendererCellReference cell, String connectorId,
-                    SimplePanel widget) {
+                               SimplePanel widget) {
+                createConnectorHierarchyChangeHandler();
+                Widget connectorWidget = null;
                 if (connectorId != null) {
                     ComponentConnector connector = (ComponentConnector) ConnectorMap
-                            .get(getConnection()).getConnector(connectorId);
-                    widget.setWidget(connector.getWidget());
+                        .get(getConnection()).getConnector(connectorId);
+                    if (connector != null) {
+                        connectorWidget = connector.getWidget();
+                        knownConnectors.add(connectorId);
+                    }
+                }
+                if (connectorWidget != null) {
+                    widget.setWidget(connectorWidget);
                 } else if (widget.getWidget() != null) {
                     widget.remove(widget.getWidget());
+                    knownConnectors.remove(connectorId);
                 }
             }
         };
@@ -66,4 +86,39 @@ public class ComponentRendererConnector
     public ComponentRendererState getState() {
         return (ComponentRendererState) super.getState();
     }
+
+    @Override
+    public void onUnregister() {
+        unregisterHierarchyHandler();
+        super.onUnregister();
+    }
+
+    /**
+     * 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.
+     */
+    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();
+                    }
+                }
+            });
+        }
+    }
+
+    private void unregisterHierarchyHandler() {
+        if (this.handlerRegistration != null) {
+            this.handlerRegistration.removeHandler();
+            this.handlerRegistration = null;
+        }
+    }
+
 }