Bind LabelInterval or MajorStep

[Oleg]

I want to dynamically change label`s interval in axis.
My chart is located inside dataTemplate, so i can achieve it only using events ChartLoaded and SeriesLoaded.

private void Series_Loaded(object sender, RoutedEventArgs e)
   {
      var series = (AreaSeries)sender;
      var pointsCount = series.DataPoints.Count;

      chart.HorizontalAxis.LabelInterval = pointsCount > 10 ? pointsCount / 10 : pointsCount;
   }

   private RadCartesianChart chart;
   private void Chart_Loaded(object sender, RoutedEventArgs e)
   {
      chart = (RadCartesianChart)sender;
   }

Is there any chance to achieve it in my viewModel, using binding?

[Kiril Stanoev]

Hello Oleg,
The axis' LabelInterval property is a dependency property and I don't see any issue binding it. Looking at your code, I suspect you'll have to use a converter as well.


Regards,
Kiril Stanoev
Telerik

[Oleg]

Hello Kiril,
Here are details - Argument Exception:

at System.Reflection.RuntimeMethodInfo.InternalInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, StackCrawlMark& stackMark)
  at System.Reflection.RuntimePropertyInfo.InternalSetValue(PropertyInfo thisProperty, Object obj, Object value, Object[] index, StackCrawlMark& stackMark)
  at System.Reflection.RuntimePropertyInfo.SetValue(Object obj, Object value, Object[] index)
  at MS.Internal.XamlMemberInfo.SetValue(Object target, Object value)
  at MS.Internal.XamlManagedRuntimeRPInvokes.SetValue(XamlTypeToken inType, XamlQualifiedObject& inObj, XamlPropertyToken inProperty, XamlQualifiedObject& inValue)
  at MS.Internal.XcpImports.Application_LoadComponentNative(IntPtr pContext, IntPtr pComponent, UInt32 cUriStringLength, String uriString, UInt32 cXamlStrLength, Byte* pXamlStr, UInt32 cAssemblyStrLength, String assemblyStr)
  at MS.Internal.XcpImports.Application_LoadComponent(IManagedPeerBase componentAsDO, String resourceLocator, UnmanagedMemoryStream stream, UInt32 numBytesToRead, String assemblyString)
  at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator)
  at PhoneApp1.MainPage.InitializeComponent()
  at PhoneApp1.MainPage..ctor()
  at System.Reflection.RuntimeConstructorInfo.InternalInvoke(RuntimeConstructorInfo rtci, BindingFlags invokeAttr, Binder binder, Object parameters, CultureInfo culture, Boolean isBinderDefault, Assembly caller, Boolean verifyAccess, StackCrawlMark& stackMark)
  at System.Reflection.RuntimeConstructorInfo.InternalInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, StackCrawlMark& stackMark)
  at System.Activator.InternalCreateInstance(Type type, Boolean nonPublic, StackCrawlMark& stackMark)
  at System.Activator.CreateInstance(Type type)
  at System.Windows.Navigation.PageResourceContentLoader.BeginLoad_OnUIThread(AsyncCallback userCallback, PageResourceContentLoaderAsyncResult result)
  at System.Windows.Navigation.PageResourceContentLoader.<>c__DisplayClass4.<BeginLoad>b__0(Object args)
  at System.Reflection.RuntimeMethodInfo.InternalInvoke(RuntimeMethodInfo rtmi, Object obj, BindingFlags invokeAttr, Binder binder, Object parameters, CultureInfo culture, Boolean isBinderDefault, Assembly caller, Boolean verifyAccess, StackCrawlMark& stackMark)
  at System.Reflection.RuntimeMethodInfo.InternalInvoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, StackCrawlMark& stackMark)
  at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)
  at System.Delegate.DynamicInvokeOne(Object[] args)
  at System.MulticastDelegate.DynamicInvokeImpl(Object[] args)
  at System.Delegate.DynamicInvoke(Object[] args)
  at System.Windows.Threading.DispatcherOperation.Invoke()
  at System.Windows.Threading.Dispatcher.Dispatch(DispatcherPriority priority)
  at System.Windows.Threading.Dispatcher.OnInvoke(Object context)
  at System.Windows.Hosting.CallbackCookie.Invoke(Object[] args)
  at System.Windows.Hosting.DelegateWrapper.InternalInvoke(Object[] args)
  at System.Windows.RuntimeHost.ManagedHost.InvokeDelegate(IntPtr pHandle, Int32 nParamCount, ScriptParam[] pParams, ScriptParam& pResult)

Here is my view:

<telerikChart:RadCartesianChart>
    <telerikChart:RadCartesianChart.HorizontalAxis>
        <telerikChart:CategoricalAxis />
    </telerikChart:RadCartesianChart.HorizontalAxis>
    <telerikChart:RadCartesianChart.VerticalAxis>
        <telerikChart:LinearAxis LabelInterval="{Binding LabelInterval}" />
    </telerikChart:RadCartesianChart.VerticalAxis>

    <telerikChart:AreaSeries ValueBinding="Value"
                                CategoryBinding="Category"
                                CombineMode="Stack"
                                ItemsSource="{Binding ChartPoints}">
    </telerikChart:AreaSeries>
</telerikChart:RadCartesianChart>

And vm:

private int _labelInterval = 1;
public int LabelInterval
{
    get { return _labelInterval; }
    set
    {
        if (_labelInterval == value)
            return;

        _labelInterval = value;
        RaisePropertyChanged("LabeInterval");
    }
}

I assign vm in code-behind:

public MainPage()
{
    InitializeComponent();
    DataContext = new ViewModel();
}

I do not know why i should use converter for this binding. 

[Oleg]

Any updates, guys?

[Victor]

Hello Oleg,

Please have a look at the attached app. It demonstrates a working example of how to bind the LabelIterval to a view model. 

Regards,
Victor
Telerik

[Oleg]

Thank you, Victor

Unfortunately it still does not work for me, please see attached screen with error.
https://dl.dropboxusercontent.com/u/7530058/error.png
It disappears when i remove binding in xaml.

P.S. i downloaded latest dll`s, run VS2012 Update3, 
my solution for WP7, your project for WP8, 
i have same problem for both plarforms

[Victor]

Hello Oleg,

Can you please clarify which version of the controls you are using? If you are using an older version the LabelInterval property might not be a dependency property. If you are not using the latest version please try it out and let us know if it still doesn't work.

Regards,
Victor
Telerik

[Victor]

Hi Oleg,

Just to clarify on my part, which is the exact version of your dlls? Also, it would be best if you post a support ticket and attach your app in a zip archive so that I can debug it.

Regards,
Victor
Telerik