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0 votes
0 answers

Is there a way to provide custom text for the labels in a PieChartSegment? I want to format the text, but haven’t been able to find a label formatter for the pie charts.

0 votes

Hello SciChart team,

How do I serialize custom tick placement and labels, generated by TickProviderAPI and LabelProvider? Actually, the main problem is that I need to export high quality (i.e. higher than actual figure size on screen) PNG images in MVVM application and method ExportToFile(fileName, ExportType.Png, false, new Size(…, …)) produces axis ticks and labels as if they were controled by original MinorDelta and MajorDelta parameters. ExportToFile() without size parameter produces output correctly, so that must be due to not-serialized TickProvider and LabeProvider properties (?), which in exported serialized surface string does not exist.

Thank you!

0 votes

I have a simple line renderable series in iOS with an SCIDateTimeAxis for X and an SCINumericAxis for Y. At this point all I’m trying to do is format the Y-axis labels and cursor labels as currency. According to the documentation, this should be as simple as:

yAxis.textFormatting = "$%f"

But it does not appear to properly use this formatting. The Y-axis is showing values like “$%f1400” when formatting a value for 14.

So, I instead attempted creating my own label provider by overriding SCINumericLabelProvider:

class CurrencyLabelProvider: SCINumericLabelProvider {

static let formatter: NumberFormatter = {
    let formatter = NumberFormatter()
    formatter.numberStyle = .currency
    return formatter

override func formatLabel(_ dataValue: SCIGenericType) -> NSAttributedString! {
    let value = dataValue.doubleData
    let string = CurrencyLabelProvider.formatter.string(from: NSNumber(value: value))!
    return NSAttributedString(string: string)

Then assigning:

yAxis.labelProvider = CurrencyLabelProvider()

This works to properly format the axis labels. So, I also override SCINumericLabelProvider to provide the cursor labels:

 override func formatCursorLabel(_ dataValue: SCIGenericType) -> NSAttributedString! {
    let value = dataValue.doubleData
    let string = CurrencyLabelFormatter.formatter.string(from: NSNumber(value: value))!
    return NSAttributedString(string: string)

This then properly formats the cursor label for the Y-axis- but it also formats the X-axis cursor:
Formatted Cursor

At this point, the X-axis is already assigned an SCIDateTimeLabelProvider- the X-axis is not assigned CurrencyLabelProvider. But it seems to be overridden by the Y-axis label provider or simply unused. The X-axis labels are formatted as dates properly, but X-axis cursor values are just numbers when not being interfered with by the Y-axis label provider.

Am I misunderstanding something or are these all bugs in the iOS SDK? We’re currently evaluating whether this package will meet our needs and it certainly appears to be riddled with issues.

  • Sean Young asked 4 months ago
  • last active 3 months ago
0 votes
0 answers

I’m using the YAxes property of the chart to data bind to a collection of NumericAxisViewModels. Is there a way to rotate the tick labels in this scenario. I can’t define a style in XAML and then assign it to the Axis because the axis is created in scichart somewhere. All I have is the axis view model. I have a LabelProvider but it doesn’t seem to support rotation unless I access the ParentAxis. Ultimately I would like to rotate some vertical axis and not other but I might be able to live with rotating all of them.

I have tried defining a style in xaml that applies to all numeric axis but it didn’t work:

<Style TargetType="{x:Type s:DefaultTickLabel}">
        <Setter Property="LayoutTransform">
                <RotateTransform Angle="-90"/>

Adding a LabelProvider sort of works but seems a little hacky and doesn’t set the scale appropriately ( I have to zoom to extends to see the labels). Is this the way I am supposed to do it?

public override string FormatLabel(IComparable dataValue) {
        var style = new Style(typeof(DefaultTickLabel));
        style.Setters.Add(new Setter(DefaultTickLabel.LayoutTransformProperty, new  RotateTransform(-90.0)));
        ParentAxis.TickLabelStyle = style;
1 vote

I am using the 2D Heatmap with text as my working prototype. I wish to have a secondary Axis on the opposite side of my man Axis that displays a count for that row or column. To display this information is simple enough through using the LabelProvider (although two lines maybe a bit tricky), and I can do some stuff with the TickProvider when it gets a bit too busy.

My question is on how I can position these TickLabels to be in the center of a row/column?

My first thought was I could be cheeky and set the margin value to offset it in its style but it seems it only works so far with the TickLabel just displayed below the tick.

        <Style x:Key="LeftAxisLabelStyle" TargetType="s:NumericTickLabel">
                   <Setter Property="Margin" Value="0,0,0,-30"/>

enter image description here

What I am trying to achieve seems to be the default positioning for column charts, and histograms. I was wondering if there is a behind the scenes option or an override I’ve missed to set this?

Alternatively annotations maybe the way to go but I get the impression that this is more for on chart labels rather than for Axis?

p.s. I think when dealing with multiple Axes, you should give an warning/error if an “Id” is not given to secondary Axis as the graph will just show blank.

0 votes

I would like to implement a custom DateTime axis LabelProvider with the following behavior:

  • Show full date and time at the start of the visible region
  • Show only time on all other ticks unless the date changes from the previous tick.

So, an axis might look like:

10/01/2016 23:00 23:30 10/02 00:00 00:30 01:00

It seems this is doable as long as 00:00:00 appears as one of the label values, but I’m not sure l can be guaranteed. It is likely that none of the entries in the series would contain that exact value. One entry might be 23:59:17 and the next 00:01:13.

Is there any way for a LabelProvider to determine what the preceding label value was?


0 votes

If I make my own implementation of AxisLabelprovider for a CategoryDatetimeAxis I get different DateTime.Kind settings depending on the function called to format a label.
I put in the values as DateTime.Kind = DateTimeKind.Utc to the DataSeries<DateTime, double>

I have this implementation for my labelprovider:

public class CategoryAxisLabelProvider : TradeChartAxisLabelProvider

    public override string FormatLabel(IComparable dataValue)
        DateTime value = (DateTime)Convert.ChangeType(dataValue, typeof(DateTime));
        if (value.Kind != DateTimeKind.Local)
            value = value.ToLocalTime();

        string s = value.ToString("HH:mm:ss\nfff 'ms'");
        return s;

    public override string FormatCursorLabel(IComparable dataValue)
        // do something

If FormatCursorLabel is called the “dataValue” has DateTime.Kind = DateTimeKind.Utc.
If FormatLabel is called the “dataValue” has Datetime.Kind = DateTimeKind.Unspecified. (Although the value is UTC)

How to handle DateTimeKind.Unspecified? Is it Utc or does it depend on what I put into the dataseries?

  • Uwe Hafner asked 4 years ago
  • last active 4 years ago
1 vote


I want to override the default AxisLabelTemplate for a DateTimeAxis beyond the normal circumstances.
Setting the AxisLabelTemplate to a StaticResource is easy enough, but all I have inside the Template is the CursorFormattedDataValue and I want to be able to send in something more then a simple string.

<ControlTemplate x:Key="RolloverModifierAxisLabelTemplateDefault">
    <Border Background="LightGray" 
            Visibility="{Binding IsXAxis, Converter={StaticResource BoolToVisibilityConverter}}">
        <TextBlock Text="{Binding CursorFormattedDataValue}" />

Extending the LabelProviderBase gives me the opportunity to override the FormatCursorLabel method, but it only returns a string and not an object and therefore I can not pass my own data structure to be used inside the AxisLabelTemplate.

How can we solve this issue? Is there a workaround, or is this something you need to implement?

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