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WPF, MVVM, and event handling for nested UserControls

I have a WPF application and am trying to implement MVVM. The main window has a viewmodel and a user control. This user control contains a text field and a button and separates the datacontext from the main parent window. Things are good...

I managed to bind a text field to a variable within the viewmodel, and it works successfully. But ... for the life of me, I cannot associate an event handler with a button on the viewmodel. I keep getting the following error:

Unable to cast object of type 'System.Reflection.RuntimeEventInfo' to type 'System.Reflection.MethodInfo'.

I know this is a common problem with new ones for MVVM. I am combing the network and nothing is working. Can anyone explain what I'm doing wrong?

Here is a sample code: Main window:

 <Window x:Class="Mvvm.View.MainWindowView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:view="clr-namespace:ZeeZor.Kiosk.Mvvm.View" WindowStyle="None" WindowState="Maximized" > <Grid > <view:ControlPanelView Margin="5, 0, 5, 0" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" > </view:ControlPanelView> </Grid> </Window>

UserControl:

 <UserControl x:Class="Mvvm.View.ControlPanelView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" > <Grid> <Grid.RowDefinitions> <RowDefinition Height="*" /> <RowDefinition Height="*" /> </Grid.RowDefinitions> <TextBlock Grid.Row="0" TextAlignment="Right" Text="{Binding Total}" Margin="0,5,20,5" /> <Button Grid.Row="1" Content="Test" Click="{Binding Path=OnClick}" Width="220" Height="100"/> </Grid> </UserControl>
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Instead, you should use Command and have the ICommand property in the ViewModel.

The Click property expects a method in a code file that cannot be bound to OnClick. Therefore, either use the command or enter only the method name from the .xaml.cs file, which should be called when the button is clicked.

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