Show Tooltips on Point, Not Slope

[Schley]

Is it possible to show a Tooltip for a data series only on the plotted points and not on the slope? I do not want the "closest" point's tooltip to be shown when the mouse hovers on the slope.

[Evgenia]

Hi Schley,

You can remove the tooltip for the line and make it visible for the PointMarks by retemplating the style for the line:

<UserControl.Resources>
    <Style x:Key="MyLineStyle"
           TargetType="telerik:Line">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="telerik:Line">
                    <Canvas x:Name="PART_MainContainer">
                        <telerik:PointMark x:Name="PART_PointMark"
                                           Canvas.Top="{TemplateBinding StartPointY}"
                                           PointMarkCanvasLeft="{TemplateBinding PointMarkCanvasLeft}"
                                           PointMarkCanvasTop="{TemplateBinding PointMarkCanvasTop}"
                                           Visibility="{TemplateBinding PointMarkVisibility}"
                                           ShapeStyle="{TemplateBinding PointMarkShapeStyle}"
                                           Style="{TemplateBinding PointMarkItemStyle}" />
                    </Canvas>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</UserControl.Resources>

Here's how to apply the Style to the Line Series:

RadChart.DefaultSeriesDefinition = new LineSeriesDefinition()
{
    ItemStyle = this.Resources["MyLineStyle"] as Style,
    ShowItemToolTips = true
};

Kind regards,
Evgenia
the Telerik team

[Schley]

Is there a way to define the resource in code? I'm using the WPF controls inside an ElementHost and loading resources is a bit of a pain. Thanks!

[Schley]

So here is what I'm trying to do. I've put the above XML into a text file and included it as an embedded resource called "NoTooltipsLineStyle":

<UserControl.Resources>
    <Style x:Key="NoTooltipLineStyle"
           TargetType="telerik:Line">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="telerik:Line">
                    <Canvas x:Name="PART_MainContainer">
                        <telerik:PointMark x:Name="PART_PointMark"
                                            Canvas.Top="{TemplateBinding StartPointY}"
                                            PointMarkCanvasLeft="{TemplateBinding PointMarkCanvasLeft}"
                                            PointMarkCanvasTop="{TemplateBinding PointMarkCanvasTop}"
                                            Visibility="{TemplateBinding PointMarkVisibility}"
                                            ShapeStyle="{TemplateBinding PointMarkShapeStyle}"
                                            Style="{TemplateBinding PointMarkItemStyle}" />
                    </Canvas>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</UserControl.Resources>

Next I'm merging said resource file with the WPF resource dictionary:

static PerfChartControl()
       {
           var wpfApp = WpfApplication.Current;

           var resDic = new ResourceDictionary
           {
               {
                   @"NoTooltipLineStyle",
                   Properties.Resources.NoTooltipLineStyle
                   },
           };

           wpfApp.Resources.MergedDictionaries.Add(resDic);
           Log.Debug(@"merged resource dictionary with new xaml application");
       }

Then I'm setting the line style:

this.perfChartControl.DefaultSeriesDefinition =
                new LineSeriesDefinition
                {ItemStyle = Resources[@"NoTooltipLineStyle"] as Style,};

All of this code compiles and runs fine, but the desired result is not occurring. For what it is worth I have also removed the UserControl.Resources element from the text I merge so that the Style element is the root node, but this has no effect.

[Evgenia]

Hi Schley,

Why don't you just point your UserControls to the ResourceDictionary object. Here's what I mean:

private void Form1_Load(object sender, EventArgs e)
{
      UserControl1 uc1 = new UserControl1();
      this.elementHost1.Controls.Add(uc1);

      uc1.Resources = resDictionary;
}

 
More information on this approach can be found here.

All the best,
Evgenia
the Telerik team