Bug 60737 - Binding to element value prevents child bindings to ViewModel
Summary: Binding to element value prevents child bindings to ViewModel
Status: RESOLVED ANSWERED
Alias: None
Product: Forms
Classification: Xamarin
Component: Android ()
Version: 2.4.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2017-11-17 18:18 UTC by Ivan Icin
Modified: 2017-11-21 15:36 UTC (History)
2 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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RESOLVED ANSWERED

Description Ivan Icin 2017-11-17 18:18:16 UTC
This is the XAML that reproduces the problem:

                 <StackLayout>
                    <Switch x:Name="switch1" IsToggled="True"/>
                    <StackLayout BindingContext="{x:Reference Name=switch1}" IsVisible="{Binding Path=IsToggled}">
                            <Label Text="{Binding Text}"/>
                    </StackLayout>
                 </StackLayout>

Text of label is not bound to the ViewModel in the case above. If StackLayout IsVisible is bound to the ViewModel and not to the element everything works fine.
Comment 1 David Ortinau [MSFT] 2017-11-21 15:36:04 UTC
Ivan,

The BindingContext on the StackLayout applies to all it's children. If you want to only reference the Switch for that property, rather that switching the entire BindingContext, just set the Source for that Binding.

<StackLayout>
        <Label Text="{Binding Text}" TextColor="Red"/>
        <Switch x:Name="switch1" IsToggled="True"/>
        <StackLayout 
            IsVisible="{Binding Source={x:Reference switch1}, Path=IsToggled}">
                <Label Text="{Binding Text}" TextColor="White" BackgroundColor="Black"/>
        </StackLayout>
     </StackLayout>