ReadMe file updated with KB

Author: jayaleshwari

README.md

@@ -1,2 +1,66 @@
-# itemtemplate-customization-node-treeview-xamarin
-How to customize TreeView ItemTemplate based on the node in Xamarin.Forms (SfTreeView)
+# How to customize TreeView ItemTemplate based on the node in Xamarin.Forms (SfTreeView)
+
+You can customize the [TreeView](https://help.syncfusion.com/xamarin/treeview/overview?) [ItemTemplate](https://help.syncfusion.com/cr/xamarin/Syncfusion.SfTreeView.XForms~Syncfusion.XForms.TreeView.SfTreeView~ItemTemplate.html?) based on the node by using [DataTemplateSelector](https://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/templates/data-templates/selector) in Xamarin.Forms.
+
+You can  also refer the following article.
+
+https://www.syncfusion.com/kb/11397/how-to-customize-treeview-itemtemplate-based-on-the-node-in-xamarin-forms-sftreeview
+
+**XAML**
+
+Binding ItemTemplateSelector to TreeView ItemTemplate.
+``` xml
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:syncfusion="clr-namespace:Syncfusion.XForms.TreeView;assembly=Syncfusion.SfTreeView.XForms"
+             xmlns:local="clr-namespace:TreeViewXamarin"
+             x:Class="TreeViewXamarin.MainPage">
+ 
+    <ContentPage.BindingContext>
+        <local:FileManagerViewModel x:Name="viewModel"/>
+    </ContentPage.BindingContext>
+ 
+    <ContentPage.Resources>
+        <ResourceDictionary>
+            <local:ItemTemplateSelector x:Key="ItemTemplateSelector" />
+        </ResourceDictionary>
+    </ContentPage.Resources>
+    <ContentPage.Content>
+        <syncfusion:SfTreeView x:Name="treeView" Indentation="15" AutoExpandMode="AllNodesExpanded" ItemTemplateContextType="Node" 
+                               ChildPropertyName="SubFiles" ItemsSource="{Binding ImageNodeInfo}" ItemTemplate="{StaticResource ItemTemplateSelector}"/>
+ 
+    </ContentPage.Content>
+</ContentPage>
+```
+**C#**
+
+Apply template to node based on SubFiles.
+``` c#
+namespace TreeViewXamarin
+{
+    public class ItemTemplateSelector : DataTemplateSelector
+    {
+        public DataTemplate _ParentTemplate { get; set; }
+        public DataTemplate _ChildTemplate { get; set; }
+        public ItemTemplateSelector()
+        {
+            this._ParentTemplate = new DataTemplate(typeof(ParentTemplate));
+            this._ChildTemplate = new DataTemplate(typeof(ChildTemplate));
+        }
+        protected override DataTemplate OnSelectTemplate(object item, BindableObject container)
+        {
+            var node = item as TreeViewNode;
+            var treeviewItem = node.Content as FileManager;
+            if (treeviewItem == null)
+                return null;
+            if (treeviewItem.SubFiles!=null)
+                return _ParentTemplate;
+            else
+                return _ChildTemplate;
+        }
+    }
+}
+```
+**Output**
+
+![ItenTemplateCustomization](https://github.com/SyncfusionExamples/itemtemplate-customization-node-treeview-xamarin/blob/master/ScreenShots/ItemTemplateCustomization.png)