Custom Tasks Fields

With the 2014 Q2 SP1 version you can now use Custom Task objects to populate the Gantt, providing you with the ability to add user defined Properties to be shown in the control.

In order to use a custom Task class you have to create a custom Provider, like the one shown in the Use CustomFields in Gantt with a simple CustomProvider KB article or the Custom EntityFramework Provider help article article. Sample Code Library can be downloaded from here.

Adding custom fields to Task with custom Entity provider

1. Use previous help article to set up custom Entity Provider

2. Create Custom Task class, inheriting from Task.

C#

public class CustomTask : Task
{
    public CustomTask() : base()
    {
    }
}

VB

Public Class CustomTask
    Inherits Task

    Public Sub New()
        MyBase.New()
    End Sub
End Class

3. Add custom property

C#

public class CustomTask : Task
{
    public string Description
    {
        get { return (string)(ViewState["Description"] ?? ""); }
        set { ViewState["Description"] = value; }
    }
}

VB

Public Class CustomTask
    Inherits Task
    ...
    Public Property Description() As String
        Get
            Return DirectCast(If(ViewState("Description"), ""), String)
        End Get
        Set(value As String)
            ViewState("Description") = value
        End Set
    End Property
End Class

4. Override GetSerializationData and LoadFromDictionary methods

C#

public class CustomTask : Task
{
    protected override IDictionary<string, object> GetSerializationData()
    {
        var dict = base.GetSerializationData();

        dict["Description"] = Description;

        return dict;
    }

    public override void LoadFromDictionary(System.Collections.IDictionary values)
    {
        base.LoadFromDictionary(values);

        Description = (string)values["Description"];
    }
}

VB

Public Class CustomTask
    Inherits Task

    Protected Overrides Function GetSerializationData() As IDictionary(Of String, Object)
        Dim dict = MyBase.GetSerializationData()

        dict("Description") = Description

        Return dict
    End Function

    Public Overrides Sub LoadFromDictionary(values As System.Collections.IDictionary)
        MyBase.LoadFromDictionary(values)

        Description = DirectCast(values("Description"), String)
    End Sub
End Class

5. Create new TaskFactory

C#

public class CustomGanttTaskFactory : ITaskFactory
{
    Task ITaskFactory.CreateTask()
    {
        return new CustomTask();
    }
}

VB

Public Class CustomGanttTaskFactory
    Implements ITaskFactory
    Private Function ITaskFactory_CreateTask() As Task Implements ITaskFactory.CreateTask
        Return New CustomTask()
    End Function
End Class

6. Override Provider TaskFactory property to return new factory

C#

public class GanttCustomProvider : GanttProviderBase
{
    public override ITaskFactory TaskFactory
    {
        get
        {
            return new CustomGanttTaskFactory();
        }
    }
}

VB

Public Class GanttCustomProvider
    Inherits GanttProviderBase
    Public Overrides ReadOnly Property TaskFactory() As ITaskFactory
        Get
            Return New CustomGanttTaskFactory()
        End Get
    End Property
End Class

7. Update Provider GetTasks Method

C#

public override List<ITask> GetTasks()
{
    var tasks = new List<ITask>();
    using (var db = new GanttDatabaseEntities())
    {
        tasks.AddRange(db.GanttTasks.ToList().Select(task => new CustomTask
        {
            ID = task.ID,
            ParentID = task.ParentID,
            Description = task.Description
        }));
    }
    return tasks;
}

VB

Public Overrides Function GetTasks() As List(Of ITask)
    Dim tasks = New List(Of ITask)()
    Using db = New GanttDatabaseEntities()

    tasks.AddRange(db.GanttTasks.ToList().[Select](Function(task) New CustomTask() With {
        .ID = task.ID,
        .ParentID = task.ParentID,
        .Description = task.Description
    }))
    End Using
    Return tasks
End Function

8. Update Provider ToEntityTask Method

C#

private GanttTask ToEntityTask(ITask srcTask)
{
    return new GanttTask
    {
        ID = (int)srcTask.ID,
        ParentID = (int?)srcTask.ParentID,
        Description = ((CustomTask)srcTask).Description
    };
}

VB

Private Function ToEntityTask(srcTask As ITask) As GanttTask

Return New GanttTask() With { 
        .ID = CInt(srcTask.ID),
        .ParentID = DirectCast(srcTask.ParentID, System.Nullable(Of Integer)),
        .Description = DirectCast(srcTask, CustomTask).Description
    }
End Function

Defining Custom Tasks Fields

To add new Custom Task Field you will have to:

1. Set the AutoGenerateColumns property to false.

2. Define new GanttBoundColumn in the Columns collection.

3. Define new GanttCustomField in the CustomTaskFields collection.

4. Defining Custom Columns:

Markup

ASP.NET

<telerik:RadGantt RenderMode="Lightweight" runat="server" ID="RadGantt1" SelectedView="WeekView" AutoGenerateColumns="false">
    <Columns>
        <telerik:GanttBoundColumn DataField="ID" Width="90px"></telerik:GanttBoundColumn>
        <telerik:GanttBoundColumn DataField="Title"></telerik:GanttBoundColumn>
        <telerik:GanttBoundColumn DataField="Description" HeaderText="Description" DataType="String" UniqueName="Description">
        </telerik:GanttBoundColumn>
    </Columns>
    <CustomTaskFields>
        <telerik:GanttCustomField PropertyName="Description" ClientPropertyName="description"  Type="String" />
    </CustomTaskFields>
</telerik:RadGantt>

Backend

C#

protected void Page_Load(object sender, EventArgs e)
{
    GanttCustomField customField = new GanttCustomField();
    customField.Type = GanttCustomFieldType.String;
    customField.PropertyName = "Description";
    customField.ClientPropertyName = "description";
    RadGantt1.CustomTaskFields.Add(customField);
}

VB

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    Dim customField As New GanttCustomField()
    customField.Type = GanttCustomFieldType.[String]
    customField.PropertyName = "Description"
    customField.ClientPropertyName = "description"
    RadGantt1.CustomTaskFields.Add(customField)
End Sub

Access Custom Task Field on the Client

The task generates getter and setter functions for the custom field client objects in the format get_<customFieldClientPropertyName>() and set_<customFieldClientPropertyName>(newValue). For example:

JavaScript

var gantt = $find("<%= RadGantt1.ClientID %>");
var task = gantt.get_tasks().getTask(0);
alert(task.get_description());
task.set_decription("my new description");

See Also

• Use CustomFields in Gantt with a simple CustomProvider

• RadGantt with Simple CustomProvider using collections in Session

• Layout

• Tasks