diff --git a/source/class/qxl/datagrid/binding/Bindings.js b/source/class/qxl/datagrid/binding/Bindings.js
index 2fb2fda..0f4564c 100644
--- a/source/class/qxl/datagrid/binding/Bindings.js
+++ b/source/class/qxl/datagrid/binding/Bindings.js
@@ -33,7 +33,9 @@ qx.Class.define("qxl.datagrid.binding.Bindings", {
    *
    * @param {qx.data.Object} model The model to add the binding to
    * @param {String} bindingId Id of binding
-   * @param {String?"binding"} bindingType The type of the binding. Either "binding" or "listener". Defaults to binding. Set to "binding " if this is a binding to a property, or "listener" if it's for a listener added with "addListener".
+   * @param {String?"binding"} bindingType The type of the binding. Either "binding", "listener", or "callback".
+   *  Defaults to binding. Set to "binding" if this is a binding to a property, or "listener" if it's
+   *  for a listener added with "addListener".
    */
   construct(model, bindingId, bindingType) {
     super();
@@ -72,18 +74,22 @@ qx.Class.define("qxl.datagrid.binding.Bindings", {
      *
      * @param {qx.core.Object} model the object with a binding
      * @param {*} bindingId the binding ID to release
-     * @param {String?} bindingType The type of the binding. Either "binding" or "listener". Defaults to auto detect.
+     * @param {String?} bindingType The type of the binding. Either "binding", "listener", or "callback". Defaults to auto detect.
      */
     add(model, bindingId, bindingType) {
       if (bindingType === undefined) {
         if (typeof bindingId == "string") {
           bindingType = "listener";
+        } else if (typeof bindingId == "function") {
+          bindingType = "callback";
         } else {
           bindingType = "binding";
         }
       } else if (qx.core.Environment.get("qx.debug")) {
         if (bindingType === "listener") {
           this.assertTrue(typeof bindingId == "string", "Invalid binding type " + bindingType + " for bindingId " + bindingId);
+        } else if (bindingType === "callback") {
+          this.assertTrue(typeof bindingId == "function", "Invalid binding type " + bindingType + " for bindingId " + bindingId);
         } else {
           this.assertTrue(typeof bindingId != "string", "Invalid binding type " + bindingType + " for bindingId " + bindingId);
         }
diff --git a/source/class/qxl/datagrid/column/Column.js b/source/class/qxl/datagrid/column/Column.js
index 3dc33ce..e7e6001 100644
--- a/source/class/qxl/datagrid/column/Column.js
+++ b/source/class/qxl/datagrid/column/Column.js
@@ -271,7 +271,10 @@ qx.Class.define("qxl.datagrid.column.Column", {
       let path = this.getPath();
       let bindings = new qxl.datagrid.binding.Bindings(model);
       if (path) {
-        if (model) {
+        if (path == ".") {
+          widget.setValue(model);
+          bindings.add(model, () => widget.setValue(null));
+        } else if (model) {
           let bindingId = model.bind(path, widget, "value", this.getBindingOptions()(widget, model));
           bindings.add(model, bindingId);
         }
@@ -323,6 +326,19 @@ qx.Class.define("qxl.datagrid.column.Column", {
       });
     },
 
+    /**
+     * Called to allow the column to update the state of the widget based on the model;
+     * this is typically used by the expansion column to show the correct icon for
+     * expanding/collapsing
+     *
+     * @param {qx.ui.core.Widget} widget
+     * @param {qx.core.Object} model
+     * @param {qxl.datagrid.ui.factory.IWidgetFactory} factory
+     */
+    updateState(widget, model, factory) {
+      // Nothing to do
+    },
+
     /**
      * Apply for `width` property
      */
diff --git a/source/class/qxl/datagrid/column/tree/ExpansionColumn.js b/source/class/qxl/datagrid/column/tree/ExpansionColumn.js
index 9d7ca55..21d9558 100644
--- a/source/class/qxl/datagrid/column/tree/ExpansionColumn.js
+++ b/source/class/qxl/datagrid/column/tree/ExpansionColumn.js
@@ -42,6 +42,18 @@ qx.Class.define("qxl.datagrid.column.tree.ExpansionColumn", {
       return new qxl.datagrid.column.tree.ExpansionWidget();
     },
 
+    /**
+     * @Override
+     */
+    updateState(widget, model, factory) {
+      let state = factory.getDataSource().getNodeStateFor(model);
+      if (state == null) {
+        return;
+      }
+      widget.setIndentationLevel(state.level);
+      widget.setState(state.state);
+    },
+
     /**
      * @Override
      */
@@ -49,7 +61,6 @@ qx.Class.define("qxl.datagrid.column.tree.ExpansionColumn", {
       let bindings = super.bindWidget(widget, model);
       let state = factory.getDataSource().getNodeStateFor(model);
       if (state == null) {
-        debugger;
         return bindings;
       }
       widget.setIndentationLevel(state.level);
diff --git a/source/class/qxl/datagrid/column/tree/ExpansionWidget.js b/source/class/qxl/datagrid/column/tree/ExpansionWidget.js
index 72d2c4f..dee6ff4 100644
--- a/source/class/qxl/datagrid/column/tree/ExpansionWidget.js
+++ b/source/class/qxl/datagrid/column/tree/ExpansionWidget.js
@@ -28,17 +28,20 @@ qx.Class.define("qxl.datagrid.column.tree.ExpansionWidget", {
   construct() {
     super();
     this._setLayout(new qxl.datagrid.column.tree.ExpansionLayout());
-    this._add(this.getChildControl("expander"));
+    let expander = this.getChildControl("expander");
+    this._add(expander);
     this._add(this.getChildControl("icon"));
     this._add(this.getChildControl("label"));
 
-    this.addListener("tap", evt => {
+    expander.addListener("tap", evt => {
       let state = this.getState();
       if (state == "open") {
         this.setState("closed");
       } else if (state == "closed") {
         this.setState("open");
       }
+      evt.preventDefault();
+      evt.stopPropagation();
     });
   },
 
@@ -182,7 +185,7 @@ qx.Class.define("qxl.datagrid.column.tree.ExpansionWidget", {
 
       let expander = this.getChildControl("expander");
       if (!icon) {
-        expander.setVisibility("hidden");
+        expander.setVisibility("excluded");
       } else {
         expander.set({
           source: icon,
@@ -198,8 +201,7 @@ qx.Class.define("qxl.datagrid.column.tree.ExpansionWidget", {
       switch (id) {
         case "expander":
           var expander = new qx.ui.basic.Image().set({
-            visibility: "hidden",
-            anonymous: true
+            visibility: "hidden"
           });
           return expander;
 
diff --git a/source/class/qxl/datagrid/ui/WidgetPane.js b/source/class/qxl/datagrid/ui/WidgetPane.js
index bc4cff7..4c00ca8 100644
--- a/source/class/qxl/datagrid/ui/WidgetPane.js
+++ b/source/class/qxl/datagrid/ui/WidgetPane.js
@@ -46,7 +46,7 @@ qx.Class.define("qxl.datagrid.ui.WidgetPane", {
       this.setDataSource(dataSource);
     }
     this._setLayout(new qxl.datagrid.ui.layout.Fixed());
-    this.addListener("tap", this.__onTap, this, true);
+    this.addListener("tap", this.__onTap, this);
   },
 
   properties: {
@@ -200,6 +200,8 @@ qx.Class.define("qxl.datagrid.ui.WidgetPane", {
             this._add(child);
             qx.ui.core.queue.Layout.add(child);
             this.__widgetFactory.bindWidget(child, model);
+          } else {
+            this.__widgetFactory.updateState(child, model);
           }
 
           const callbackArguments = [model, child, currentRelativePosition, currentAbsolutePosition];
diff --git a/source/class/qxl/datagrid/ui/factory/AbstractWidgetFactory.js b/source/class/qxl/datagrid/ui/factory/AbstractWidgetFactory.js
index a744d1e..071b77a 100644
--- a/source/class/qxl/datagrid/ui/factory/AbstractWidgetFactory.js
+++ b/source/class/qxl/datagrid/ui/factory/AbstractWidgetFactory.js
@@ -123,6 +123,14 @@ qx.Class.define("qxl.datagrid.ui.factory.AbstractWidgetFactory", {
       widget.dispose();
     },
 
+    /**
+     * @override
+     */
+    updateState(widget, model) {
+      let bindingData = widget.getUserData("qxl.datagrid.factory.AbstractWidgetFactory.bindingData");
+      bindingData.column.updateState(widget, model, this);
+    },
+
     /**
      * Called to create a widget
      *
diff --git a/source/class/qxl/datagrid/ui/factory/IWidgetFactory.js b/source/class/qxl/datagrid/ui/factory/IWidgetFactory.js
index 0987ade..da7648d 100644
--- a/source/class/qxl/datagrid/ui/factory/IWidgetFactory.js
+++ b/source/class/qxl/datagrid/ui/factory/IWidgetFactory.js
@@ -60,6 +60,16 @@ qx.Interface.define("qxl.datagrid.ui.factory.IWidgetFactory", {
      */
     unbindWidget(widget) {},
 
+    /**
+     * Called to allow the column to update the state of the widget based on the model;
+     * this is typically used by the expansion column to show the correct icon for
+     * expanding/collapsing
+     *
+     * @param {qx.ui.core.Widget} widget
+     * @param {qx.core.Object} model
+     */
+    updateState(widget, model) {},
+
     /**
      * Obtains the model which is bound to the widget
      *