MVVM Support
The Telerik RadTimeBar control can be used with great success with the Model-View-ViewModel (MVVM) pattern. This help topic will demonstrate how to use the control with the pattern.
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Create new ViewModel class that inherits the ViewModelBase abstract class:
public class ExampleViewModel : ViewModelBase { private DateTime periodStart; private DateTime periodEnd; private IEnumerable<double> data; private DateTime visiblePeriodStart; private DateTime visiblePeriodEnd; [TypeConverter(typeof(DateTimeTypeConverter))] public DateTime PeriodStart { get { return this.periodStart; } set { if (this.periodStart == value) return; this.periodStart = value; this.OnPropertyChanged("PeriodStart"); } } [TypeConverter(typeof(DateTimeTypeConverter))] public DateTime PeriodEnd { get { return this.periodEnd; } set { if (this.periodEnd == value) return; this.periodEnd = value; this.OnPropertyChanged("PeriodEnd"); } } [TypeConverter(typeof(DateTimeTypeConverter))] public DateTime VisiblePeriodStart { get { return this.visiblePeriodStart; } set { if (this.visiblePeriodStart == value) return; this.visiblePeriodStart = value; this.OnPropertyChanged("VisiblePeriodStart"); } } [TypeConverter(typeof(DateTimeTypeConverter))] public DateTime VisiblePeriodEnd { get { return this.visiblePeriodEnd; } set { if (this.visiblePeriodEnd == value) return; this.visiblePeriodEnd = value; this.OnPropertyChanged("VisiblePeriodEnd"); } } public IEnumerable<double> Data { get { if (data == null) { Random r = new Random(); List<double> collection = new List<double>(); for (DateTime date = PeriodStart; date <= PeriodEnd; date = date.AddDays(1)) { collection.Add(r.Next(0, 100)); } this.data = collection; } return this.data; } } }
Public Class ExampleViewModel Inherits ViewModelBase Private periodStart_Renamed As Date Private periodEnd_Renamed As Date Private data_Renamed As IEnumerable(Of Double) Private visiblePeriodStart_Renamed As Date Private visiblePeriodEnd_Renamed As Date <TypeConverter(GetType(DateTimeTypeConverter))> Public Property PeriodStart() As Date Get Return Me.periodStart_Renamed End Get Set(ByVal value As Date) If Me.periodStart_Renamed Is value Then Return End If Me.periodStart_Renamed = value Me.OnPropertyChanged("PeriodStart") End Set End Property <TypeConverter(GetType(DateTimeTypeConverter))> Public Property PeriodEnd() As Date Get Return Me.periodEnd_Renamed End Get Set(ByVal value As Date) If Me.periodEnd_Renamed Is value Then Return End If Me.periodEnd_Renamed = value Me.OnPropertyChanged("PeriodEnd") End Set End Property <TypeConverter(GetType(DateTimeTypeConverter))> Public Property VisiblePeriodStart() As Date Get Return Me.visiblePeriodStart_Renamed End Get Set(ByVal value As Date) If Me.visiblePeriodStart_Renamed Is value Then Return End If Me.visiblePeriodStart_Renamed = value Me.OnPropertyChanged("VisiblePeriodStart") End Set End Property <TypeConverter(GetType(DateTimeTypeConverter))> Public Property VisiblePeriodEnd() As Date Get Return Me.visiblePeriodEnd_Renamed End Get Set(ByVal value As Date) If Me.visiblePeriodEnd_Renamed Is value Then Return End If Me.visiblePeriodEnd_Renamed = value Me.OnPropertyChanged("VisiblePeriodEnd") End Set End Property Public ReadOnly Property Data() As IEnumerable(Of Double) Get If data_Renamed Is Nothing Then Dim r As New Random() Dim collection As New List(Of Double)() Dim [date] As Date = PeriodStart Do While [date] <= PeriodEnd collection.Add(r.Next(0, 100)) [date] = [date].AddDays(1) Loop Me.data_Renamed = collection End If Return Me.data_Renamed End Get End Property End Class
The PeriodStart and PeriodEnd properties will specify the time period that the TimeBar will visualize. The VisiblePeriodStart and VisiblePeriodEnd properties will specify the visible time period on the screen. The Data collection will be used as datasource for the SparkLines that will be seen inside the TimeBar control.
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Add new RadTimeBar and RadSparkLine declarations in XAML and bind the mentioned properties:
The properties should be bound using TwoWay binding. This is required because of the coercing of the values that happens when a binding is executed.
<UserControl.DataContext> <local:ExampleViewModel PeriodStart="01/01/2012" PeriodEnd="01/01/2013" VisiblePeriodStart="01/01/2012" VisiblePeriodEnd="01/01/2013" /> </UserControl.DataContext> <Grid x:Name="LayoutRoot" Background="White"> <telerik:RadTimeBar Margin="8,8,8,0" Height="150" VerticalAlignment="Top" PeriodStart="{Binding PeriodStart, Mode=TwoWay}" PeriodEnd="{Binding PeriodEnd, Mode=TwoWay}" VisiblePeriodStart="{Binding VisiblePeriodStart, Mode=TwoWay}" VisiblePeriodEnd="{Binding VisiblePeriodEnd, Mode=TwoWay}"> <telerik:RadTimeBar.Intervals> <telerik:YearInterval/> <telerik:QuarterInterval/> <telerik:MonthInterval/> <telerik:WeekInterval /> <telerik:DayInterval /> </telerik:RadTimeBar.Intervals> <telerik:RadLinearSparkline ItemsSource="{Binding Data}" /> </telerik:RadTimeBar> </Grid>
The result can be seen below: