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TabControl - UserControls inside DataTemplates are not rendered

See original GitHub issue

When using DataTemplates in a TabControl, if the DataTemplate contains a UserControl, the UserControl won’t be displayed.

Example

<TabControl>
    <TabControl.DataTemplates>
      <DataTemplate DataType="vms:SampleViewModel">
        <StackPanel Orientation="Vertical">
          <TextBlock Text="SampleViewModel.."/>
          <local:SampleView />
        </StackPanel>
      </DataTemplate>
    </TabControl.DataTemplates>
    <TabItem Header="Tab 1 - Content from DataTemplate"><vms:SampleViewModel /></TabItem>
    <TabItem Header="Tab 2" Content="Content for item 2"/>
    <TabItem Header="Tab 3 - View without DataTemplate"><local:SampleView /> </TabItem>
</TabControl>

When I select Tab 1, it shows me my DataTemplate but any UserControl (local:SampleView) inside the DataTemplate is not displayed, it only shows the TextBlock If I select Tab 3, the UserControl (local:SampleView) is shown properly…

Issue Analytics

State:
Created 5 years ago
Comments:11 (6 by maintainers)

Top GitHub Comments

1reaction

ksignecommented, Jan 4, 2019

@braca In ContentPresenter.cs:249 replace if (newChild.Parent == null && TemplatedParent == null) to if (newChild.Parent == null) It will help though side effects are not clear yet.

0reactions

grokyscommented, Jan 5, 2019

@Gillibald yeah it’s really not obvious. I think there might be a better way…

Should be fixed by https://github.com/AvaloniaUI/Avalonia/pull/2218 btw.