TreeView Control in Visual Studio LightSwtch 2011

Introduction

Visual Studio LightSwitch is a Microsoft tool for building business applications. There are many Silverlight controls available in Visual Studio LightSwitch. In which Treeview is a also Silverlight control. Treeview is used for displaying data in a tree form. We can say that when we want to display our data in a hierarchal format then we can use the Treeview control in a LightSwitch application. Reference by (http://lightswitchhelpwebsite.com/)

How to use Treeview control

Step 1 : First of all open Visual Studio LightSwitch->New project->Select LightSwitch application->Write name (TreeviewControl)->Ok.

Step 2 : Click on create new table.

Step 3 : Create table like as Category.

Step 4 : Now we will establish a relationship among Categories table.

Click on relationship->select name and multiplicity->ok.

Step 5 : Now we will add a screen. Right click on screens->Add screen.

Step 6 : Select Editable Grid Screen->Select screen data (Categories)->Ok.

Step 7 : Click on add data item->Select query->select categories->Write name (CategoriesTree)->ok.

Step 8 : Click on EditQuery in CategoriesTree.

Step 9 : Click on filter->Select IsRootNode>Select literal->True.

Step 10 : Go to menu bar->File->Add->New project.

Step 11 : Select Silverlight->Select Silverlight Class library->Write name (SilverlightProject)->Ok->Select Silverlight 4->Ok.

Step 12 : Right click on SilverlightProject->Add references.

Step 13 : Browse (C:\Program Files\Visual Studio 2010\Common7\IDE\LightSwitch\1.0\client)->Select Microsoft.LightSwitch.Base.Client.dll, Microsoft.LightSwitch.Client.dll and Microsoft.LightSwitch.dll->Ok.

Step 14 : Now delete the class1.cs from SilverlightProject.

Step 15 : Now we will add a new class. Right click on SilverlightProject->Add->New item.

Step 16 : Select Class->Write name (EntityCollectionValueConverter.cs)->Add->Write code.

code : Reference by LightSwitchHelpWebsite

using System;
using System.Windows.Data;
using Microsoft.LightSwitch;
using System.Diagnostics;
using System.Collections.ObjectModel;
using System.Collections.Generic;
namespace SilverlightProject
{
public class EntityCollectionValueConverter : IValueConverter
{
public object Convert(object value,
Type targetType,
object parameter,
System.Globalization.CultureInfo culture)
{
string strErrorMessage
= "Converter parameter set to the property name that will serve as data source";
IEntityObject entity = value as IEntityObject;
if (entity == null)
throw new ArgumentException("The converter using an entity object");
string sourcePropertyName = parameter as string;
if (string.IsNullOrWhiteSpace(sourcePropertyName))
throw new ArgumentException(strErrorMessage);
var entities = new ObservableCollection<IEntityObject>();
var temporaryEntites = new List<IEntityObject>();
entity.Details.Dispatcher.BeginInvoke(delegate
{
IEntityCollection eCollection =
entity.Details.Properties[sourcePropertyName].Value as IEntityCollection;
if (eCollection == null)
{
Debug.Assert(false, "The property is " + sourcePropertyName + " not an entity collection");
return;
}
foreach (IEntityObject e in eCollection)
{
temporaryEntites.Add(e);
}
Microsoft.LightSwitch.Threading.Dispatchers.Main.BeginInvoke(delegate
{
foreach (IEntityObject e in temporaryEntites)
{
entities.Add(e);
}
});
});
return entities;
}
public object ConvertBack(object value,
Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
}

Step 17 : Now we will add Silverlight User Control.

Right click on SilverlightProject->Add->New item->Select Silverlight User Control->Write name (SilverlightTreeControl.xaml)->Add->Write xaml code.