Change Content Template on Button Click Wpf

I have the following XAML:

<Window 
       xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
       Title="WpfApplication4" Height="300" Width="300">
    <Window.Resources>
        <ControlTemplate x:Key="simpleErrorTemplate">
            <TextBox Margin="10,10,10,5" TextWrapping="Wrap" VerticalScrollBarVisibility="Auto" Text="T1" />
        </ControlTemplate>
        <ControlTemplate x:Key="detailedErrorTemplate">
            <StackPanel>
                <TextBox Margin="10,10,10,5" TextWrapping="Wrap" VerticalScrollBarVisibility="Auto" Text="T2" />
                <TextBox Margin="10,10,10,5" TextWrapping="Wrap" VerticalScrollBarVisibility="Auto" Text="T3" />
                <TextBox Margin="10,10,10,5" TextWrapping="Wrap" VerticalScrollBarVisibility="Auto" Text="T4" />
            </StackPanel>
        </ControlTemplate>
    </Window.Resources>
    <Grid>
        <ContentControl>
            <ContentControl.Style>
                <Style TargetType="ContentControl">
                    <Setter Property="Template"
                        Value="{StaticResource simpleErrorTemplate}"/>
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding ElementName=Button,Path=IsPressed}" Value="True">
                            <Setter Property="Template" Value="{StaticResource detailedErrorTemplate}"/>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </ContentControl.Style>
        </ContentControl>
        <Button x:Name="Button" Content="Button" Height="40" Width="129" Margin="88,5,76,5" Grid.Row="1" Click="Button_Click1"/>
    </Grid>
</Window>

I had like to change the GUI style the moment I click the button just like it happends when DataTrigger is set for the Checkbox.

The code Behind looks as follows however the moment I click the button the window closes and no result.

import wpf
from System.Windows import Application, Window

class MyWindow(Window):
    def __init__(self):
        self.ui = wpf.LoadComponent(self, 'WpfApplication4.xaml')

    def Button_Click1(self, sender, e):
        self.ContentTemplate = Window.Resources.FindName(self,'detailedErrorTemplate') 

if __name__ == '__main__':
    Application().Run(MyWindow())

Why the template wont change?

Thank you.

Solution

I am unfamiliar with ironpython, but in your click handler it looks like you're setting the ContentTemplate of your window, which seems incorrect. I assume your detailedErrorTemplate is supposed to apply to your ContentControl. In this case you need to add x:Name to your ContentControl (i.e.: x:Name="TheContentControl") in order to reference the ContentControl in your code behind and set (in c#)

TheContentControl.Template = this.Resources["detailedErrorTemplate"] as ControlTemplate;

You have key's for your resources, not Names, so you need to index the resource dictionary by the key.

Edit details based on comments.

In your xaml, change your line
```
<ContentControl>
```

 <ContentControl x:Name="TheContentControl">

Since we now have a name for the ContentControl, you can properly change the ControlTemplate of the ContentControl (NOT the window. I understand that your ContentControl effectively encompasses the Window, but you can't just assign that ControlTemplate meant for the ContentControl to the Window like that). Change your line of code from:
```
self.ContentTemplate = Window.Resources.FindName(self,'detailedErrorTemplate')
```

to (I hope I'm doing the syntax correctly).

 self.TheContentControl.Template = self.Resources['detailedErrorTemplate']