Unable to create abstract parent class

Question

The following code compiles and runs perfectly in both WPF and Silverlight:

public abstract class ParentPage:Page
{
}
public sealed partial class BlankPage : ParentPage
{
    public BlankPage()
    {
        InitializeComponent();
    }
}

But in WinRT I get this error which only disappears if you remove the abstract:

XAML Type 'ParentPage' cannot be constructed. It needs to have a default constructor' 

I often have abstract parent classes for my controls, because I want to ensure that they cannot be instantiated.  Hope this can be fixed.

...Stefan

Answer 1

Hi Stefan,

like the error message states: You need a default constructor in your abstract class, for example:

public abstract class ParentPage : Page
{
    public ParentPage()
    {
        ...
    }
}

---

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Answer 2

Thanks for the suggestion, unfortunately when the code is like this that gives the same error message:

public abstract class ParentPage:Page
{
    public ParentPage()
    {
    }
}
public sealed partial class BlankPage : ParentPage
{
    public BlankPage()
    {
        InitializeComponent();
    }
}

XAML Type 'ParentPage' cannot be constructed. It needs to have a default constructor

Stefan

Answer 3

This is fixed in RP