I cant get DependencyProperty.Register to work. It requires (string, string, string, PropertyMetadata) instead of

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Asked: May 26, 20262026-05-26T09:17:20+00:00 2026-05-26T09:17:20+00:00

I cant get DependencyProperty.Register to work. It requires (string, string, string, PropertyMetadata) instead of

0

I cant get DependencyProperty.Register to work.

It requires (string, string, string, PropertyMetadata) instead of string, Type, Type, UIPropertyMeatdata)…

I changed the UI-PropertyMetadata part but can’t get string part of it to work.
I tried typeof(T).ToString() and just "T" but it doesn’t work.

My code looks like this

public ObservableCollection<RingSegment> RingSegments {
    get { return (ObservableCollection<RingSegment>)GetValue(RingSegmentsProperty); }
    set { SetValue(RingSegmentsProperty, value); }
}
public static readonly DependencyProperty RingSegmentsProperty = DependencyProperty.Register(
    "RingSegments", typeof(ObservableCollection<RingSegment>), typeof(MainPage), new PropertyMetadata(new ObservableCollection<RingSegment>()));

And errors that i get

Error 1 The best overloaded method match for 'Windows.UI.Xaml.DependencyProperty.Register(string, string, string, Windows.UI.Xaml.PropertyMetadata)' has some invalid arguments C:\Users\aleksandar.toplek\documents\visual studio 11\Projects\Project - XX\XX\MainPage.xaml.cs 21 68 XX

Error 2 Argument 2: cannot convert from 'System.Type' to 'string' C:\Users\aleksandar.toplek\documents\visual studio 11\Projects\Project - XX\XX\MainPage.xaml.cs 22 20 XX

Error 3 Argument 3: cannot convert from 'System.Type' to 'string' C:\Users\aleksandar.toplek\documents\visual studio 11\Projects\Project - XX\XX\MainPage.xaml.cs 22 63 XX

— EDIT —

When I do this

public static readonly DependencyProperty RingSegmentsProperty = DependencyProperty.Register(
    "RingSegments", "ObservableCollection<RingSegment>", "MainPage", new PropertyMetadata(new ObservableCollection<RingSegment>()));

Code compiles but throws exception in runtime

A first chance exception of type 'System.TypeInitializationException' occurred in mscorlib.dll

in file XamplTypeIngo.g.cs

System.TypeInitializationException was unhandled by user code
  Message=The type initializer for 'XX.MainPage' threw an exception.
  Source=mscorlib
  TypeName=XX.MainPage
  StackTrace:
       at System.Runtime.CompilerServices.RuntimeHelpers._RunClassConstructor(RuntimeType type)
       at System.Runtime.CompilerServices.RuntimeHelpers.RunClassConstructor(RuntimeTypeHandle type)
       at Disk_Visualizer.XamlTypeInfo.XamlUserType.RunInitializer() in c:\Users\aleksandar.toplek\Documents\Visual Studio 11\Projects\Project - XX\XX\obj\Debug\XamlTypeInfo.g.cs:line 277
  InnerException: System.NullReferenceException
       Message=Object reference not set to an instance of an object.
       Source=Windows.UI.Xaml
       StackTrace:
            at Windows.UI.Xaml.DependencyProperty.Register(String name, String propertyTypeName, String ownerTypeName, PropertyMetadata typeMetadata)
            at Disk_Visualizer.MainPage..cctor() in c:\Users\aleksandar.toplek\Documents\Visual Studio 11\Projects\Project - XX\XX\MainPage.xaml.cs:line 21
       InnerException:  
...