Hi,

Is there any way to implement annotation text in line or stepline chart?
I want to show some annotation text over ChartArea.
How can I achive that?

I have attached the image of desired chart.

Thanks

Hi,
I made TextAnnotation based on AnnotationBase,
But some objects are interals, so I can't calculate X,Y position.

I realy need this.
Somebody help me.


  <Style TargetType="local:TextAnnotation">
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="local:TextAnnotation">
          <Canvas x:Name="PART_RootElement" Background="Transparent">
            <Border Background="{TemplateBinding Background}" Margin="{TemplateBinding Margin}"
                    Canvas.Left="{TemplateBinding ActualX}" Canvas.Top="{TemplateBinding ActualY}">
              <ContentControl VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                            HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                            VerticalAlignment="{TemplateBinding VerticalAlignment}" HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
                            FontFamily="{TemplateBinding FontFamily}"
                            >
                <ContentControl.Content>
                  <TextBlock Text="{TemplateBinding Text}" TextTrimming="WordEllipsis" Margin="2"
                           Foreground="{TemplateBinding Foreground}"
                           ToolTipService.ToolTip="{TemplateBinding Text}"/>
                </ContentControl.Content>
              </ContentControl>
            </Border>
          </Canvas>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>

  public class TextAnnotation : AnnotationBase
  {

    public TextAnnotation()
    {
      this.DefaultStyleKey = typeof(TextAnnotation);
    }

    protected override void Update()
    {
       // base.ChartArea is interal!!!
    }

    public static readonly DependencyProperty TextProperty = DependencyProperty.Register("Text", typeof(string), typeof(TextAnnotation), new PropertyMetadata("note"));
    public string Text
    {
      get { return (string)base.GetValue(TextProperty); }
      set { base.SetValue(TextProperty, value); }
    }

    public static readonly DependencyProperty XProperty = DependencyProperty.Register("X", typeof(double), typeof(TextAnnotation), new PropertyMetadata(0d, X_OnChanged));
    public double X
    {
      get { return (double)base.GetValue(XProperty); }
      set { base.SetValue(XProperty, value); }
    }

    public static readonly DependencyProperty YProperty = DependencyProperty.Register("Y", typeof(double), typeof(TextAnnotation), new PropertyMetadata(0d, Y_OnChanged));
    public double Y
    {
      get { return (double)base.GetValue(YProperty); }
      set { base.SetValue(YProperty, value); }
    }

    public static void X_OnChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
    {
      ((TextAnnotation) o).ActualX = (double) e.NewValue;
      // convert data to cavas.Y ???
    }

    public static void Y_OnChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
    {
      ((TextAnnotation)o).ActualY = (double)e.NewValue;
      // convert data to canvas.Y ???
    }

    public static readonly DependencyProperty ActualXProperty = DependencyProperty.Register("ActualX", typeof(double), typeof(TextAnnotation), new PropertyMetadata(0d));
    public double ActualX
    {
      get { return (double)base.GetValue(ActualXProperty); }
      internal set { base.SetValue(ActualXProperty, value); }
    }

    public static readonly DependencyProperty ActualYProperty = DependencyProperty.Register("ActualY", typeof(double), typeof(TextAnnotation), new PropertyMetadata(0d));
    public double ActualY
    {
      get { return (double)base.GetValue(ActualYProperty); }
      internal set { base.SetValue(ActualYProperty, value); }
    }

  }
}

Hi Yonghan,

 You can show text in annotation zone by re-templating it. I have attached a project, showing this.

Hope this helps.

All the best,
Evgeni "Zammy" Petrov
the Telerik team

Thank you Zammy.
I appreciate that.

But I have more problems.
_ I can't see MarkedZone under line series (ToolTipService is not working)
_ overflowed text is clipped.

Can I set hover effect to MarkedZone?

Thanks.

Hi Yonghan,

To be able to see the Tooltips for MarkedZones you should retemplate the Chart Area and put the Annotations Layer within the Zoom Layer for example. Then by using TooltipService.ToolTip property of the MarkedZone you can set custom tooltip. You can find a sample project attached demonstrating what I mean.
Additionally to make the text in MarkedZone wrapped (this way the overflowed text does not clips) 
you can set the TextWrapping property of the MarkedZone's Text Block to Wrap. You can find this set in the MarkedZones Style.

I hope this helps.

Greetings,
Evgenia Milcheva
the Telerik team