RadCartesianChart iOS Zooming issue

[Hady]

I am facing an issue regarding Xamarin Telerik RadCartesianChart, While zooming with setting the GapLength="0.9" MajorTickInterval="30",
No new labels created or rendered to the chart as predicted, it works normally for android but on iOS it does nothing just zooming without rendering the hidden labels as happened at the Android platform,
Kindly advice if there are any other attribute should be set to make this functionality work

ViewModel Code

01.using System.Collections.ObjectModel;
02.using System.Windows.Input;
03.using Prism.Navigation;
04.using Xamarin.Forms;
05.
06.namespace Demo.ViewModels
07.{
08.    public class CategoricalData
09.    {
10.        public object Category { get; set; }
11.
12.        public double Value { get; set; }
13.    }
14.    public class ChartPageViewModel : BaseViewModel
15.    {
16.        private ObservableCollection<CategoricalData> _data;
17.
18.        public ObservableCollection<CategoricalData> Data
19.        {
20.            get => _data;
21.            set
22.            {
23.                //_data = value;
24.                SetProperty(ref _data, value);
25.                RaisePropertyChanged(nameof(Data));
26.            }
27.        }
28.        public ChartPageViewModel()
29.        {
30.            LoadDummyData();
31.        }
32.
33.        public void LoadDummyData()
34.        {
35.           var dData = new ObservableCollection<CategoricalData>();
36.            for (int i = 0; i < 300; i++)
37.            {
38.                dData.Add(new CategoricalData { Category = i, Value = (i%10 > 0)?( (i%2>0)? (i%30):(i%20)): 5 });
39.            }
40.
41.            Data = dData;
42.        }
43.
44.
45.    }
46.}

 

Xaml Code

01.<?xml version="1.0" encoding="utf-8" ?>
02.<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
03.             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
04.             xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms"
05.             xmlns:chart="clr-namespace:Telerik.XamarinForms.Chart;assembly=Telerik.XamarinForms.Chart"
06.             prism:ViewModelLocator.AutowireViewModel="True" BackgroundColor="{StaticResource BackgroundColor}"
07.             x:Class="Demo.Views.ChartPage">
08.
09.
10.            <chart:RadCartesianChart x:Name="chart" BackgroundColor="Transparent" Grid.Row="1" >
11.                <chart:RadCartesianChart.ChartBehaviors>
12.                    <chart:ChartPanAndZoomBehavior ZoomMode="Horizontal" PanMode="Horizontal" />
13.                </chart:RadCartesianChart.ChartBehaviors>
14.                <chart:RadCartesianChart.HorizontalAxis >
15.                    <OnPlatform x:TypeArguments="chart:CartesianAxis">
16.                        <On Platform="Android">
17.                            <chart:CategoricalAxis LineColor="#A9A9A9" MajorTickThickness="2" PlotMode="BetweenTicks" LabelFitMode="None"
18.                                                   MajorTickBackgroundColor="#A9A9A9" GapLength="0.9" MajorTickInterval="50" LabelTextColor="White" ShowLabels="True"/>
19.                        </On>
20.                        <On Platform="iOS">
21.                            <chart:CategoricalAxis LineColor="#A9A9A9" MajorTickThickness="2" PlotMode="BetweenTicks" LabelFitMode="None"
22.                                                   MajorTickBackgroundColor="#A9A9A9" GapLength="0.9" MajorTickInterval="30"  LabelTextColor="White" ShowLabels="True" />
23.                        </On>
24.                    </OnPlatform>
25.                </chart:RadCartesianChart.HorizontalAxis>
26.                <chart:RadCartesianChart.VerticalAxis>
27.                    <chart:NumericalAxis LabelTextColor="White" ShowLabels="True" Minimum="0" Maximum="80" LineColor="#A9A9A9" MajorTickBackgroundColor="#A9A9A9" />
28.                </chart:RadCartesianChart.VerticalAxis>
29.                <chart:RadCartesianChart.Series>
30.                    <chart:LineSeries CategoryBinding="Category" ValueBinding="Value" ItemsSource="{Binding Data}" />
31.                </chart:RadCartesianChart.Series>
32.                <chart:RadCartesianChart.Grid>
33.                    <chart:CartesianChartGrid MajorLinesVisibility="XY" MajorLineThickness="1"/>
34.                </chart:RadCartesianChart.Grid>
35.
36.            </chart:RadCartesianChart>
37.
38.</ContentPage>

 

Development Environment:

• iOS 12.1
• Xamarin Forms 3.2

[Yana]

Hi Hady,

I am afraid you've stumbled upon a known issue in RadChart on iOS platform - we have it logged in our public portal, so you could track its status at the link below:
https://feedback.progress.com/Project/168/feedback/Details/248289-chart-ios-missing-labels-after-pan-zoom-action

There isn't a feasible workaround I could suggest.  In addition, I've updated its priority per your report.

I am sorry for any inconvenience caused.

Regards,
Yana
Progress Telerik