WPF UserControl inheriting another UserControl

Question

I am trying to inherit an usercontrol in WPF the way mentioned in How can a WPF UserControl inherit a WPF UserControl?

namespace DMS.Presentation
{
    /// <summary>
    /// Interaction logic for WorkSpaceViewControl
    /// </summary>
    public abstract class WorkSpaceViewControl : UserControl
    {
        public WorkSpaceViewControl()
        {
            InitializeComponent();
        }

    private void InitializeComponent()
        {

        }
    }  

}

And code doesn't give any error thus far. But when I inherit it in a new usercontrol:

namespace DMS.Presentation
{
    /// <summary>
    /// Interaction logic for AnimalWorkSpaceView.xaml
    /// </summary>
    public partial class AnimalWorkSpaceView : WorkSpaceViewControl
    {
        public AnimalWorkSpaceView()
        {
            InitializeComponent();
        }

    }

}

And it's XAML file is:

//I have tried both WorkSpaceViewControl:UserControl and UserControl:WorkSpaceViewControl here


<UserControl:WorkSpaceViewControl x:Class="DMS.Presentation.WorkSpaceViewControl"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:DMS.Presentation"
             xmlns:WorkSpaceViewControl="clr-namespace:DMS.Presentation"
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">

</UserControl:WorkSpaceViewControl>

I get a message that partial modifier doesn't exist. Another Partial Declaration of WorkSpaceViewControl exists. So how should I implement it and where have things gone wrong? My whole project is stuck due to this inheritance bottle-neck since January. Help will be really appreciated.

score 9 · Accepted Answer · answered Mar 10 '15 at 08:14

According to the answer you've referenced, your derived UserControl XAML should look more like this:

<local:WorkSpaceViewControl x:Class="DMS.Presentation.AnimalWorkSpaceView"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:local="clr-namespace:DMS.Presentation"
    mc:Ignorable="d" 
    d:DesignHeight="300" d:DesignWidth="300">
</local:WorkSpaceViewControl>

You had declared two different XML namespaces, local and WorkSpaceViewControl, both referring to "clr-namespace:DMS.Presentation". You need just one of them (so I kept local, it being more idiomatic), and you need to use the namespace to qualify the type name WorkSpaceViewControl.

Thus, the XAML declaration starts as <local:WorkSpaceViewControl ...

In addition, the x:Class value for your derived class needs to be the derived class, not the base class. So instead of "DMS.Presentation.WorkSpaceViewControl", that should be set to "DMS.Presentation.AnimalWorkSpaceView" as shown above.

WPF UserControl inheriting another UserControl

1 Answers1