Grouping

The timeline items in a RadTimeline control can be displayed in groups. Additionally, groups of timeline items can be made expandable/collapsible.

Setting up the RadTimeline

In order to demonstrate the Grouping feature of the control, we will define a model and a viewmodel as demonstrated in Example 1.

Example 1: Defining the model and viewmodel

public class RadTimelineDataItem 
{ 
    public DateTime StartDate { get; set; } 
 
    public TimeSpan Duration { get; set; } 
 
    public string GroupName { get; set; } 
} 
 
public class RadTimelineGroupingViewModel 
{ 
    public RadTimelineGroupingViewModel() 
    { 
        this.PeriodStart = DateTime.Today; 
        this.PeriodEnd = DateTime.Today.AddYears(1); 
        this.VisiblePeriodStart = DateTime.Today; 
        this.VisiblePeriodEnd = DateTime.Today.AddMonths(1); 
 
        this.GenerateTimelineData(); 
    } 
 
    public DateTime PeriodStart { get; set; } 
 
    public DateTime PeriodEnd { get; set; } 
 
    public DateTime VisiblePeriodStart { get; set; } 
 
    public DateTime VisiblePeriodEnd { get; set; } 
 
    public ObservableCollection<RadTimelineDataItem> TimelineItems { get; set; } 
 
    private void GenerateTimelineData() 
    { 
        Random random = new Random(); 
        ObservableCollection<RadTimelineDataItem> items = new ObservableCollection<RadTimelineDataItem>(); 
 
        for (DateTime date = this.PeriodStart; date < this.PeriodEnd; date = date.AddDays(2)) 
        { 
            items.Add(new RadTimelineDataItem() { StartDate = date, Duration = TimeSpan.FromDays(random.Next(0, 10)), GroupName = string.Format("Group{0}", random.Next(1, 4)) }); 
        } 
 
        this.TimelineItems = items; 
    } 
} 
Public Class RadTimelineDataItem 
    Public Property StartDate() As Date 
 
    Public Property Duration() As TimeSpan 
 
    Public Property GroupName() As String 
End Class 
 
Public Class RadTimelineGroupingViewModel 
    Public Sub New() 
        Me.PeriodStart = Date.Today 
        Me.PeriodEnd = Date.Today.AddYears(1) 
        Me.VisiblePeriodStart = Date.Today 
        Me.VisiblePeriodEnd = Date.Today.AddMonths(1) 
 
        Me.GenerateTimelineData() 
    End Sub 
 
    Public Property PeriodStart() As Date 
 
    Public Property PeriodEnd() As Date 
 
    Public Property VisiblePeriodStart() As Date 
 
    Public Property VisiblePeriodEnd() As Date 
 
    Public Property TimelineItems() As ObservableCollection(Of RadTimelineDataItem) 
 
    Private Sub GenerateTimelineData() 
        Dim random As New Random() 
        Dim items As New ObservableCollection(Of RadTimelineDataItem)() 
 
        Dim [date] As Date = Me.PeriodStart 
        Do While [date] < Me.PeriodEnd 
            items.Add(New RadTimelineDataItem() With { 
                .StartDate = [date], 
                .Duration = TimeSpan.FromDays(random.Next(0, 10)), 
                .GroupName = String.Format("Group{0}", random.Next(1, 4)) 
            }) 
            [date] = [date].AddDays(2) 
        Loop 
 
        Me.TimelineItems = items 
    End Sub 
End Class 

Group Expand Modes

In order to enable grouping, you have to set the GroupPath property of the RadTimeline to a property of the model. In the following examples, we will be setting the GroupPath property to the GroupName property of the RadTimelineDataItem class defined in Example 1. After that all RadTimelineDataItem objects with the same GroupName will be placed in the same group.

Through the GroupExpandMode property of the RadTimeline, you can control whether the groups in the RadTimeline can be expanded/collapsed. It can be set to the following values:

  • None (Default): A value of None indicates that the groups of timeline items are expanded by default and cannot be collapsed.

    Example 2: Setting the GroupExpandMode property to None

        <!-- GroupPath is specified and GroupExpandMode is set to None --> 
        <Grid> 
            <Grid.DataContext> 
                <local:RadTimelineGroupingViewModel /> 
            </Grid.DataContext> 
            <telerik:RadTimeline PeriodStart="{Binding PeriodStart}" 
                                PeriodEnd="{Binding PeriodEnd}" 
                                VisiblePeriodStart="{Binding VisiblePeriodStart}" 
                                VisiblePeriodEnd="{Binding VisiblePeriodEnd}" 
                                StartPath="StartDate" 
                                DurationPath="Duration" 
                                GroupPath="GroupName" 
                                GroupExpandMode="None" 
                                ItemsSource="{Binding TimelineItems}"> 
                <telerik:RadTimeline.Intervals> 
                    <telerik:YearInterval /> 
                    <telerik:MonthInterval /> 
                    <telerik:WeekInterval /> 
                    <telerik:DayInterval /> 
                </telerik:RadTimeline.Intervals> 
            </telerik:RadTimeline> 
        </Grid> 
    

    Figure 1: Result from Example 2

    Rad Timeline-features-grouping-0-Group Expand Mode-None

  • Single: A value of Single indicates that only one group of timeline items can be expanded at a time. By default, all groups of timeline items are collapsed in this mode.

    Example 3: Setting the GroupExpandMode to Single

        <!-- GroupPath is specified and GroupExpandMode is set to Single --> 
        <Grid> 
            <Grid.DataContext> 
                <local:RadTimelineGroupingViewModel /> 
            </Grid.DataContext> 
            <telerik:RadTimeline PeriodStart="{Binding PeriodStart}" 
                                PeriodEnd="{Binding PeriodEnd}" 
                                VisiblePeriodStart="{Binding VisiblePeriodStart}" 
                                VisiblePeriodEnd="{Binding VisiblePeriodEnd}" 
                                StartPath="StartDate" 
                                DurationPath="Duration" 
                                GroupPath="GroupName" 
                                GroupExpandMode="Single" 
                                ItemsSource="{Binding TimelineItems}"> 
                <telerik:RadTimeline.Intervals> 
                    <telerik:YearInterval /> 
                    <telerik:MonthInterval /> 
                    <telerik:WeekInterval /> 
                    <telerik:DayInterval /> 
                </telerik:RadTimeline.Intervals> 
            </telerik:RadTimeline> 
        </Grid> 
    

    Figure 2: Result from Example 3

    Rad Timeline-features-grouping-1-Group Expand Mode-Single

  • Multiple: A value of Multiple indicates that multiple groups of timeline items can be expanded at a time. By default, all groups of timeline items are collapsed in this mode.

    Example 4: Setting the GroupExpandMode to Multiple

        <!-- GroupPath is specified and GroupExpandMode is set to Multiple --> 
        <Grid> 
            <Grid.DataContext> 
                <local:RadTimelineGroupingViewModel /> 
            </Grid.DataContext> 
            <telerik:RadTimeline PeriodStart="{Binding PeriodStart}" 
                                PeriodEnd="{Binding PeriodEnd}" 
                                VisiblePeriodStart="{Binding VisiblePeriodStart}" 
                                VisiblePeriodEnd="{Binding VisiblePeriodEnd}" 
                                StartPath="StartDate" 
                                DurationPath="Duration" 
                                GroupPath="GroupName" 
                                GroupExpandMode="Multiple" 
                                ItemsSource="{Binding TimelineItems}"> 
                <telerik:RadTimeline.Intervals> 
                    <telerik:YearInterval /> 
                    <telerik:MonthInterval /> 
                    <telerik:WeekInterval /> 
                    <telerik:DayInterval /> 
                </telerik:RadTimeline.Intervals> 
            </telerik:RadTimeline> 
        </Grid> 
    

    Figure 2: Result from Example 4

    Rad Timeline-features-grouping-2-Group Expand Mode-Multiple

Changing the default collapsed state of expandable groups

The styles used in this section are implicit. In order to apply them you have to use NoXAML DLL-s. For more information check the Implicit Styles topic.

By default, the groups of timeline items are collapsed when the GroupExpandMode is set to either Single or Multiple. You can use the following style to change this default state:

Example 5: Setting the IsExpanded property of the TimelineItemGroupControl through a style

<!-- If you don't use NoXAML dlls you don't need the BasedOn setting. See the note in the begining of this help section. --> 
<Window.Resources> 
<Style TargetType="telerik:TimelineItemGroupControl" BasedOn="{StaticResource TimelineItemGroupControlStyle}"> 
    <Setter Property="IsExpanded" Value="True" /> 
</Style> 
</Window.Resources> 
In order to change the default state of specific groups of timeline items, you can use a converter:

Example 6: Setting the IsExpanded property of the TimelineItemGroupControl with a converter

<!-- If you don't use NoXAML dlls you don't need the BasedOn setting. See the note in the begining of this help section. --> 
<Window.Resources> 
<Style TargetType="telerik:TimelineItemGroupControl" BasedOn="{StaticResource TimelineItemGroupControlStyle}"> 
    <Setter Property="IsExpanded" Value="{Binding GroupKey, Converter={StaticResource groupKeyToIsExpandedConverter}}" /> 
</Style> 
</Window.Resources> 

Example 7: Defining the GroupKeyToIsExpandedConverter

public class GroupKeyToIsExpandedConverter : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) 
    { 
        string groupKey = value as string; 
 
        if (groupKey != null && groupKey == "Group1") 
            return true; 
 
        return false; 
    } 
 
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) 
    { 
        throw new NotImplementedException(); 
    } 
} 
Public Class GroupKeyToIsExpandedConverter 
    Implements IValueConverter 
    Public Function Convert(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object 
        Dim groupKey As String = TryCast(value, String) 
 
        If groupKey IsNot Nothing AndAlso groupKey = "Group1" Then 
            Return True 
        End If 
 
        Return False 
    End Function 
 
    Public Function ConvertBack(value As Object, targetType As Type, parameter As Object, culture As CultureInfo) As Object 
        Throw New NotImplementedException() 
    End Function 
End Class 
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