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Getting Started

Both RadCartesianChart and RadPolarChart contain an Annotations collection which holds all the annotations plotted against the chart.

The RadChartView will visualize annotations only if it populated with data.

Adding Cartesian Annotations

When adding GridLine or PlotBand annotations to RadCartesianChart, you have to explicitly set their Axis property to either the vertical or the horizontal axis. That way the annotation knows what its orientation is, and also, the exact coordinates on which it has to be rendered.

<telerik:RadCartesianChart x:Name="cartesianChart"> 
 
    <telerik:RadCartesianChart.Annotations> 
        <telerik:CartesianGridLineAnnotation Axis="{Binding ElementName=verticalAxis}"  
                                                Value="6" Stroke="Red" StrokeThickness="1"/> 
        <telerik:CartesianGridLineAnnotation Axis="{Binding ElementName=horizontalAxis}"  
                                                Value="2.8" Stroke="Blue" StrokeThickness="1"/> 
    </telerik:RadCartesianChart.Annotations> 
 
    <telerik:RadCartesianChart.VerticalAxis> 
        <telerik:LinearAxis x:Name="verticalAxis"/> 
    </telerik:RadCartesianChart.VerticalAxis> 
 
    <telerik:RadCartesianChart.HorizontalAxis> 
        <telerik:LinearAxis x:Name="horizontalAxis"/> 
    </telerik:RadCartesianChart.HorizontalAxis> 
</telerik:RadCartesianChart>     

cartesianChart.Annotations.Add( 
    new CartesianGridLineAnnotation  
    {  
        Axis = cartesianChart.VerticalAxis,  
        Value = 6, Stroke = new SolidColorBrush(Colors.Red),  
        StrokeThickness = 1 
    }); 
cartesianChart.Annotations.Add( 
    new CartesianGridLineAnnotation  
    {  
        Axis = cartesianChart.HorizontalAxis,  
        Value = 2.8, Stroke = new SolidColorBrush(Colors.Blue),  
        StrokeThickness = 1 
    }); 
cartesianChart.Annotations.Add(New CartesianGridLineAnnotation() With { _ 
    .Axis = cartesianChart.VerticalAxis, _ 
    .Value = 6, _ 
    .Stroke = New SolidColorBrush(Colors.Red), _ 
    .StrokeThickness = 1 _ 
}) 
cartesianChart.Annotations.Add(New CartesianGridLineAnnotation() With { _ 
    .Axis = cartesianChart.HorizontalAxis, _ 
    .Value = 2.8, _ 
    .Stroke = New SolidColorBrush(Colors.Blue), _ 
    .StrokeThickness = 1 _ 
}) 

Adding Polar Annotations

When adding GridLine or PlotBand annotations to RadPolarChart, you do not need to set their axis association as it is implicitly resolved by their respective type. For example, PolarAxisGridLineAnnotation is implicitly associated with the polar axis, while RadialAxisPlotBandAnnotation is implicitly associated with the radial axis.

<telerik:RadPolarChart> 
 
    <telerik:RadPolarChart.Annotations> 
        <telerik:PolarAxisGridLineAnnotation Value="2" Stroke="Red"/> 
        <telerik:PolarAxisGridLineAnnotation Value="7" Stroke="LightGreen"/> 
        <telerik:PolarAxisGridLineAnnotation Value="8" Stroke="LightBlue"/> 
    </telerik:RadPolarChart.Annotations> 
 
    <telerik:RadPolarChart.RadialAxis> 
        <telerik:NumericRadialAxis/> 
    </telerik:RadPolarChart.RadialAxis> 
 
    <telerik:RadPolarChart.PolarAxis> 
        <telerik:PolarAxis/> 
    </telerik:RadPolarChart.PolarAxis> 
 
</telerik:RadPolarChart> 

polarChart.Annotations.Add( 
    new PolarAxisGridLineAnnotation { Value = 2, Stroke = new SolidColorBrush(Colors.Red) }); 
polarChart.Annotations.Add( 
    new PolarAxisGridLineAnnotation { Value = 7, Stroke = new SolidColorBrush(Colors.LightGreen) }); 
polarChart.Annotations.Add( 
    new PolarAxisGridLineAnnotation { Value = 8, Stroke = new SolidColorBrush(Colors.LightBlue) }); 
polarChart.Annotations.Add(New PolarAxisGridLineAnnotation() With { _ 
    .Value = 2, _ 
    .Stroke = New SolidColorBrush(Colors.Red) _ 
}) 
polarChart.Annotations.Add(New PolarAxisGridLineAnnotation() With { _ 
    .Value = 7, _ 
    .Stroke = New SolidColorBrush(Colors.LightGreen) _ 
}) 
polarChart.Annotations.Add(New PolarAxisGridLineAnnotation() With { _ 
    .Value = 8, _ 
    .Stroke = New SolidColorBrush(Colors.LightBlue) _ 
}) 
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