DataContext in not working when I implement MainWindow with some other class

Question

I'm new in WPF and I'm doing following code below as:

 public partial class MainView : ViewModelControl
    {
        public MainView()
        {
            InitializeComponent();
            this.DataContext = new ViewModel1();
        }
}

As you can see I have my own class ViewModelControl. I have the following code below fro ViewModelControl class as:

 public partial class ViewModelControl : Window, IViewModelControl
    {
        public virtual void bindFirstDataContext()
        {
        }
        public virtual void bindSecondDataContext()
        {
        }
    }

I Modify the following XAML as:

<Window x:Class="WpfApplication1.View.MainView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainView" Height="262" Width="316">

Now the issue is that its show's error "Partial declarations of 'WpfApplication1.View.MainView' must not specify different base classes". It's not working as before as When I implement it with Window class as by default. Where I'm doing wrong?

Answer 1

Base class for partial class declarations should be same. You have changed Window in code behind to ViewModelControl so that needs to be updated in XAML as well.

Change XAML declaration to this:

<local:ViewModelControl
        x:Class="WpfApplication1.View.MainView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:Namespace"> <-- HERE replace Namepsace with
                                                   actual namespace of class
                                                   ViewModelControl.

 ....
</local:ViewModelControl/>