Is it possible to display only one or multiple DataMarker based ShowMarker ?

[sujeet kumar]

            <chart:SfChart x:Name="chart">

                <chart:SfChart.Series>

                    <chart:LineSeries

                            ItemsSource ="{Binding ChartPoints}" XBindingPath="DateTime"

                            YBindingPath="Value" EnableTooltip="True" StrokeWidth="5">

                        <chart:LineSeries.DataMarker>

                            <chart:ChartDataMarker

                                MarkerColor="Red"

                                ShowMarker="{Binding IsMarkerVisible}" //// -----This part its not working.

                                ShowLabel="False"

                                MarkerWidth="20"

                                MarkerHeight="20"

                                MarkerType="Diamond" />

                        </chart:LineSeries.DataMarker>

                 </chart:LineSeries>

 </chart:SfChart.Series>

</chart:SfChart>

[Yuvaraj Palanisamy]

Hi Sujeet Kumar,

We have achieved your requiremnt “Want to show DataMarker symbol based on IsMarkerVisible model property” with the help of DataMarkerLabelCreated event. Please find the code example below.

CodeSnippet:

<chart:LineSeries ItemsSource="{Binding Data1}"

                      XBindingPath="XValue"

                      YBindingPath="YValue"

                      DataMarkerLabelCreated="LineSeries_DataMarkerLabelCreated">

    <chart:LineSeries.DataMarker>

        <chart:ChartDataMarker ShowLabel="False"

                               ShowMarker="True"

                               MarkerHeight="10"

                               MarkerWidth="10"

                               MarkerType="Pentagon"

                               MarkerColor="Red"/>

 

    </chart:LineSeries.DataMarker>

</chart:LineSeries>

void LineSeries_DataMarkerLabelCreated(System.Object sender, Syncfusion.SfChart.XForms.ChartDataMarkerLabelCreatedEventArgs e)

{

    var data = e.DataMarkerLabel.Data as Model;

    if(!data.IsMarkerVisible)

    {

        e.DataMarkerLabel.MarkerColor = Color.Transparent;

    }

}

We have attached the sample for your reference. Please find the sample from the below attachment.

Output:

For more details, please refer the below link

https://www.syncfusion.com/kb/11979/how-to-show-different-data-marker-symbols-based-on-condition-in-xamarin-forms-charts

https://www.syncfusion.com/kb/10922/how-to-add-a-custom-data-marker-in-xamarin-forms-chart

Please let us know if you have any further assistance.

Regards,

Yuvaraj.

Attachment: ChartSample_DataMarker_aab54958.zip

[sujeet kumar]

Thanks for your quick reply,

But here is the problem let us say I have 500K data1 items, Now only 2 items i need to show Data marked on chart.

So as per the above solution, it will trigger 500K times to check each condition, Then this will be the problem for performance.

[Devakumar Dhanapoosanam]

Hi Sujeet Kumar,

We can show one or multiple marker shapes for larger data points without affecting performance using below solution

Solution 1: Annotation

Using Annotation instead of DataMarker based on your requirement for one or multiple data point values and add all annotation in the ChartAnnotations collection.

Please refer the below link for more details

https://help.syncfusion.com/xamarin/charts/chartannotation#shape-annotation

https://help.syncfusion.com/xamarin/charts/chartannotation#ellipse-annotation

https://help.syncfusion.com/xamarin/charts/chartannotation#positioning-the-annotation

Solution 2: ScatterSeries

We can achieve your requirement by adding collection of data with one or multiple data points as per your requirement and adding one additional ScatterSeries or FastScatterSeries. We can set the data collection for scatter series ItemsSource property instead of adding DataMarker for huge data points.

https://help.syncfusion.com/xamarin/charts/charttypes#scatter-chart

https://help.syncfusion.com/xamarin/charts/charttypes#fast-scatter-chart

Please let us know if you need any further assistance on this.

Regards,

Devakumar D