Vertical axis custom labels width

[Viollier]

Hi,

i have a Xamarin iOS chart that uses custom labels. My issue is the width of the Vertical axis labels: for a certain data set, the default vertical labels look like "0.22, 0.4599999999, 1.2999999999...."; when i set the custom labels to "0.1,  0.4, 5 ....", the width of the labels remains very big, just as if the large labels were still showing. The same thing happens if i set the range to something like "0.4599999999...." - the custom labels will have a lot of padding.

How can i force the labels to resize?

Thanks!

[Adrian]

Hi, Viollier,

Thank you for writing.
Could you, please, send me a code snippet of your setup so I could investigate the issue further? Thank you in advance for your cooperation.

Regards,
Adrian
Telerik by Progress

[Viollier]

Hi Adrian,

here is my code:

Initially:
private void SetupChart()
        {
            Chart = new TKChart(CGRect.Inflate(ChartContainerView.Bounds, 0, 0);
            Chart.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
            Chart.Delegate = chartDelegate;
            ChartContainerView.AddSubview(Chart);
        }

Then, when the ChartModel becomes available, i start customising it:


        Chart.AllowAnimations = true;

        Chart.BeginUpdates();

        Chart.RemoveAllData();           
        var dataPoints = GetDataPoints();
        var series = new TKChartLineSeries(dataPoints.ToArray());
        StyleSeries(series);
        Chart.AddSeries(series);
        var axis = new TKChartDateTimeAxis(ChartModel.MinDate, ChartModel.MaxDate);
        AdjustXAxis(axis);
        Chart.XAxis = axis;
        AdjustYAxisRange();

        Chart.EndUpdates();

        AddChartBandAnnotation();
        StyleChart();

Here are the details of the methods i am using:

    void StyleSeries(TKChartLineSeries series)
    {
        ........
        palette settings, stroke colors, etc
        ........
    }

    void StyleChart()
    {
        Chart.GridStyle.HorizontalLinesHidden = true;
        Chart.GridStyle.HorizontalFill = null;
        Chart.GridStyle.HorizontalAlternateFill = null;
        Chart.GridStyle.VerticalLinesHidden = false;
        Chart.GridStyle.VerticalFill = null;
        Chart.GridStyle.VerticalAlternateFill = null;

    }

    void AdjustYAxisRange()
    {
        Range axisRange = ChartModel.RoundedVerticalAxisRange();
        Chart.YAxis.Range = new TKRange(new NSNumber(axisRange.Min), new NSNumber(axisRange.Max));

        //force the axis not to display any default labels
        ((TKChartNumericAxis)Chart.YAxis).MajorTickInterval = axisRange.Span;
    }

    //Call this after EndUpdates();
    void AddChartBandAnnotation()
    {
        Chart.RemoveAllAnnotations();

        var range = GetChartBandRange();
        if (range != null)
        {
            var fillColor = new UIColor(0.83f, 0.92f, 0.88f, 0.6f);
            var strokeColor = new UIColor(0.6f, 0.85f, 0.76f, 0.8f);
            var fill = new TKSolidFill(fillColor);
            var stroke = new TKStroke(strokeColor, 1.5f);
            var annotation = new TKChartBandAnnotation(range, Chart.YAxis, fill, stroke);
            Chart.AddAnnotation(annotation);
        }

        var labels = GetVerticalAxisLabels();
        if (labels.Count > 0)
        {
            Chart.YAxis.CustomLabels = labels;
            Chart.YAxis.Style.LabelStyle.TextAlignment = TKChartAxisLabelAlignment.Left;
            Chart.YAxis.Style.LabelStyle.FirstLabelTextAlignment = TKChartAxisLabelAlignment.Left;
            Chart.YAxis.Style.LabelStyle.TextOffset = new UIOffset(2, 0);
            Chart.YAxis.Style.LabelStyle.FirstLabelTextOffset = new UIOffset(2, 0);

            Chart.YAxis.Style.LabelStyle.TextHidden = false;

        }
        else
        {
            Chart.YAxis.Style.LabelStyle.TextHidden = true;
        }


        Chart.YAxis.AllowPan = false;
        Chart.YAxis.AllowZoom = false;
        AdjustYAxisRange();
        Chart.Update();

    }

Thanks!

[Adrian]

Hello Viollier,

Thank you for the code snippet. I can confirm that this issue exists in TKChart. The width of the axis is measured considering the width of the default labels not the custom ones. I logged this issue and it will be addressed in a future release. I also updated your Telerik points for reporting this issue.
A possible workaround is to use the axis' LabelFormat property to format the labels with 0 digits after the decimal point. I hope this helps.

Regards,
Adrian
Telerik by Progress