Tooltip for line chart

[Manishkumar]

Hi,

I have turned on show tooltip property to true for line chart in custom chart(4 line series + stack series). But when i hover last point in line chart though it is plotted correctly, doesnt display value correctly. It is displaying value of previous point.In this case, I had set show point marks = false.

Please help.

Thanks and Regards,
Manish

[Evgeni "Zammy" Petrov]

Hi Manishkumar,

 When you hover over a line, the data point that is used as a context is the previous one.
So if you hover over the last line segment you will get information for the data point before the last one.
To get tooltip for the last one you will need to hover over its label or data point.

If you do not get tooltip for last data point from its label or point mark, please send us a project so we can check it out.

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

[Michal]

Hi!

I've encountered the same problem. Is it possible to disable showing of the tooltip when mouse is over a line and only show it when it's over a point on a line?

thanks
Michal

[Missing User]

Hello,

You can remove the tooltip for the line and to leave it for the PointMark by retemplating the style of the Line. For example:

<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>

and set this style for RadChart.DefaultSeriesDefinition.ItemStyle:

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

Kind regards,

Polina

the Telerik team

[Martin Roussel]

Hi, i have a similar problem (using Q3 2010 SP1) but in my case, it is not showing the previous point but like 13 behind. My serie has 117 points in total and finishes with the following Y values (in acending order): ....3712, 3720, 3720,3721,3721,3722,3722,3723,3723,2724,3724. Maybe im not aiming with my cursor enough to hit the end but the highest value i get in my tooltip is 3712 when hovering the really end. The problem seems worse the more we add points to the serie. When i add more point (7451 points in total), Im also experiencing some tooltip not appearing at all when putting the cursor on the line...it finally appears when hovering by the 3/4 of the line.

If i cant fix it, is there a way i can put a static tooltip at the end on the line with the highest value? If not, the only i see is forcing a label in the legend serie's tooltip.


Reply to Evgeni "Zammy" Petrov : what do you mean by "hover over its label"? Im not sure what is the label you mean?

TIA

[Missing User]

Hello Martin Roussel,

I tried to reproduce this issue in local tests, but it works as expected. In the attached file you can find my test project. If you still encounter this issue, could you please modify it to replicate the unwanted behavior or submit another working project that demonstrates it? We will debug it locally, and advise you further.

Regards,

Polina

the Telerik team

[Martin Roussel]

Thanks for the reply Polina.

The first differences i can see right from the start is im not using itemssource binding to map my dataset to the chart. Im creating manually the points (point = New DataPoint), the series (seriesData.Add(point)) and adding them to the chart after (xChart.DefaultView.ChartArea.DataSeries.Add(seriesData)). Maybe source binding work better? So i tried to replicate your code in VB, but weird results

Public Class DummyData

    Private mdblXValue As Double
    Private mdblYValue As Double

    Public Property XValue() As Double
        Get
            Return mdblXValue
        End Get
        Set(ByVal value As Double)
            mdblXValue = value
        End Set
    End Property

    Public Property YValue() As Double
        Get
            Return mdblYValue
        End Get
        Set(ByVal value As Double)
            mdblYValue = value
        End Set
    End Property

End Class
.
.
.

                       newlist = New List(Of DummyData)

                            For j = 0 To seriesData.Count - 1
                                item = New DummyData
                                item.XValue = seriesData(j).XValue
                                item.YValue = seriesData(j).YValue
                                newlist.Add(item)
                            Next

                            xChart.ItemsSource = newlist

The chart appears but with 2 series (i dont know where the second comes from??). The real problem i have is how to use your method (list binding) when having more than 1 serie to show?

Can you please help?

[Missing User]

Hi Martin Roussel,

Based on the information provided, I am unsure why the chart renders two series. In case this issue persists, it will be helpful if you provide more information about how you setup the chart and bind the data.

You can populate RadChart with data in two ways:
-- Manually, by adding chart points - DataPoints.
-- With data binding by using SeriesMapping/ItemMapping.
The second approach and more concrete the manual series mapping gives you a full control on how the data is bound to the chart. It also gives you the opportunity to bind to nested collections. Basically, each nested collection will be a chart series. Please note that RadChart supports nested collections via SeriesMapping.CollectionIndex property. For additional information on populating RadChart with nested collections, please refer to the following online resources:
http://demos.telerik.com/silverlight/#Chart/Gallery/Line
http://www.telerik.com/help/silverlight/radchart-populating-with-data-data-binding-to-nested-collections.html

I hope this helps.

Kind regards,

Polina

the Telerik team