Hello guys, 

I was looking in the documentation of the Charts whether it is possible to show data points in the line like this in the attached picture ? I was not able to find it. Could you please provide some information.

 

 

Hello.
Tell me how to get the items that are currently displayed on the chart after zooming and scrolling?
I use custom renderer to get native control and handle pan and zoom events using PanZoomListener, but in the handler I can only get relative offset.

here is my renderer

    class ChartPointRenderer : CartesianChartRenderer
    {
        public ChartPointRenderer(Context context) :base(context)
        {
        }
        protected override RadCartesianChartView CreateNativeControl()
        {
             Control = base.CreateNativeControl();
             return Control;
        }
        protected override void OnAttachedToWindow()
        {
            base.OnAttachedToWindow();
            var beh = Control.Behaviors.ToArray();
            for (int j = 0; j < beh.Length; j++)
            {
                if (beh[j].GetType() == typeof(Telerik.XamarinForms.ChartRenderer.Android.AndroidChartPanAndZoomBehavior))
                {
                    var zoomBehavior = (Telerik.XamarinForms.ChartRenderer.Android.AndroidChartPanAndZoomBehavior)beh[j];
                    zoomBehavior.AddPanZoomListener(new Listeners.ChartPanZoomListener());
                }
            }
        }
    }



and listener

    public class ChartPanZoomListener :Java.Lang.Object, IPanZoomListener
    {

        public IntPtr Handle => throw new NotImplementedException();

        public void OnPan(double p0, double p1)
        {
            //do something
        }

        public void OnZoom(double p0, double p1)
        {
            //do something
        }
    }

Hi i have problem creating multi axes chart for iOS.

Im trying to do something like the image attached and i read a lot of documentation but all of that is using native controller for iOS.
I have done creating this on android using customrenderer.

Is there any way to show the bar series YAXIS to right side of the chart? 
Here's how my approach using custom renderer on iOS.






I'm stuck here for 2 days creating custom renderer for iOS but none of them succeed.

Thanks

Is there any properties about Palette for xaml ?
I want to change the bar color. But I only find the method which use code behind(custom palette).
My practice is not like the example provided on the official website.(http://docs.telerik.com/devtools/xamarin/controls/chart/how-to/chart-how-to-create-custom-palette)
Can you help me if I want to change the bar color which use xaml?
I hope it can be implemented like this:

<telerikChart:ChartPalette>
    <telerikChart:PaletteEntry FillColor="Green"/>
    <telerikChart:PaletteEntry FillColor="Blue"/>
</telerikChart:ChartPalette>

"  at playing.Views.Dashboard.ConstructUtilisationBarGraph () [0x0014f] in /Users/marshallhp/Projects/playing/playing/Views/Dashboard.xaml.cs:50 \n  at playing.Views.Dashboard..ctor () [0x0002f] in /Users/marshallhp/Projects/playing/playing/Views/Dashboard.xaml.cs:25 \n  at playing.Views.MainPage.NavigateFromMenu (System.Int32 id) [0x000a0] in /Users/marshallhp/Projects/playing/playing/Views/MainPage.xaml.cs:42 \n  at playing.Views.MenuPage.<.ctor>b__3_1 (System.Object sender, Xamarin.Forms.SelectedItemChangedEventArgs e) [0x0004b] in /Users/marshallhp/Projects/playing/playing/Views/MenuPage.xaml.cs:47 \n  at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__7_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1021 \n  at Foundation.NSAsyncSynchronizationContextDispatcher.Apply () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.21/src/Xamarin.iOS/Foundation/NSAction.cs:178 \n--- End of stack trace from previous location where exception was thrown ---\n\n  at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)\n  at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.21/src/Xamarin.iOS/UIKit/UIApplication.cs:86 \n  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0000e] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.21/src/Xamarin.iOS/UIKit/UIApplication.cs:65 \n  at playing.iOS.Application.Main (System.String[] args) [0x00001] in /Users/marshallhp/Projects/playing/playing.iOS/Main.cs:17 "

 

Hi team, followed the example here (https://docs.telerik.com/devtools/xamarin/controls/chart/series/cartesian/line-series) and get this error in iOS simulator.

 

Any help would be greatly appreciated. 

Hi!

I'm using RadCartesianChartView in my Xamarin.Android project. When there are no data to display I see "No Data" message. How can i customize it? I need to change text and textcolor for this message.

When our data is loaded and have a null value it causes crash to our app and catches an "Object reference not set to an instance of an object". 
But this issue is only happening on iOS platform. Can someone help me this is a crucial issue for me and my team. 

{System.NullReferenceException: Object reference not set to an instance of an object
  at Telerik.XamarinForms.ChartRenderer.iOS.ManagedChartDataSource.AddPoints (TelerikUI.TKChartSeries series, System.Collections.IList newItems) [0x00196] in <22603cf6132d4ae9966514a9a3d3a88a>:0 
  at Telerik.XamarinForms.ChartRenderer.iOS.BaseChartRenderer`1[T].Telerik.XamarinForms.Chart.IChartRenderer.OnSeriesSourceCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e, System.Object series) [0x0004e] in <22603cf6132d4ae9966514a9a3d3a88a>:0 
  at Telerik.XamarinForms.Chart.ChartSeries.OnItemsSourceCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00017] in <22603cf6132d4ae9966514a9a3d3a88a>:0 
  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00018] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/external/corefx/src/System.ObjectModel/src/System/Collections/ObjectModel/ObservableCollection.cs:263 
  at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedAction action, System.Object item, System.Int32 index) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/external/corefx/src/System.ObjectModel/src/System/Collections/ObjectModel/ObservableCollection.cs:338 
  at System.Collections.ObjectModel.ObservableCollection`1[T].InsertItem (System.Int32 index, T item) [0x0001a] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/external/corefx/src/System.ObjectModel/src/System/Collections/ObjectModel/ObservableCollection.cs:196 
  at System.Collections.ObjectModel.Collection`1[T].Add (T item) [0x00020] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/external/corefx/src/Common/src/CoreLib/System/Collections/ObjectModel/Collection.cs:71 
  at NutritionalFitness.Mobile.ViewModels.ProgramPhaseViewModel.SetGraphsData (System.Collections.Generic.IEnumerable`1[T] weightIns, System.Collections.Generic.IEnumerable`1[T] waterIntakes) [0x00152] in D:\Work\NutritionalFitness\NutritionalFitness.Dev\NutritionalFitnessMobile\NutritionalFitness.Mobile\ViewModels\ProgramPhaseViewModel.cs:184 
  at NutritionalFitness.Mobile.ViewModels.ProgramPhaseViewModel.SetProgramPhaseComponents () [0x002d4] in D:\Work\NutritionalFitness\NutritionalFitness.Dev\NutritionalFitnessMobile\NutritionalFitness.Mobile\ViewModels\ProgramPhaseViewModel.cs:90 }

Starting from 2018.3.912.1 (was not able to reproduce in 2018.2.821.1 or earlier), loading charts on iOS crashes the device. This happens in the sample project SDKBrowser provided as well, when opening any of the Series charts (specifically the Vertical Bar which is what we have been using).

Stack trace of the crash:

 

 

This is happening on iOS Simulator 12.4, and on device on iOS 13.0. The current workaround is to stay on the old version of 2018.2.*, but this is not really a good workaround.

I have a graph with a time scale of hours, and in the tooltip I am interested to see also the hours.

They asked something similar in 2016 and it was answered that it was not possible, any news?

https://www.telerik.com/forums/formatting-of-the-tooltip-text 

 

thanks in advance :-)

Hi there,

I have a question regarding pie chart redrawing. I am not sure if it works, but is it possible to dynamically update the values of an existing pie chart?

I was able to display the chart when page started(image1 in attach files). I am trying to trigger an event through Xamarin Picker and update the number of the same chart.I was able to change the variable(an ObservableCollection), but the chart never changed.

Is there anything I missed?