How to bind two different class properties in DataTemplate

Question

I am trying to bind two properties from different classes in DataTemplate.

<DataTemplate x:Key="DemoItemTemplate" x:DataType="local:DemoInfo">
   <NavigationViewItem Visibility="{Binding Visibility, Mode=TwoWay}" Content="{x:Bind Name}"/>
</DataTemplate>

DataType set as DemoInfo for this DataTemplate and Name value updated from DemoInfo.

I have tried view model as source and relative source binding. But Visibility property binding not working from ViewModel class. Any suggest how to achieve this?

Visibility="{Binding Visibility, Source={StaticResource viewModel}}"

score 0 · Answer 1 · answered Oct 23 '20 at 14:37

0

AFAIK , you cant use multibinding in UWP , you can try to use Locator What is a ViewModelLocator and what are its pros/cons compared to DataTemplates?

answered Oct 23 '20 at 14:37

Vladislav

9
2

Nico Zhu · Answer 2 · 2020-10-27T01:30:15.480

How to bind two different class properties in DataTemplate

If you bind Visibility with StaticResource, please declare ViewModel class in your page Resources like the following.

ViewModel

public class ViewModel
{
    public ViewModel()
    {
        Visibility = false;
    }
    public bool Visibility { get; set; }
}

Xaml

<Page.Resources>
    <local:ViewModel x:Key="ViewModel" />
</Page.Resources>


<DataTemplate x:DataType="local:Item">
        <TextBlock
            Width="100"
            Height="44"
            Text="{x:Bind Name}"
            Visibility="{Binding Visibility, Source={StaticResource ViewModel}}" />
    </StackPanel>
</DataTemplate>

Update

If you want Visibility value changed dynamically at run-time, you need implement INotifyPropertyChanged interface for ViewModel class.

public class ViewModel : INotifyPropertyChanged
{
    public ViewModel()
    {
        Visibility = false;
    }
    private bool _visibility;
    public bool Visibility
    {
        get
        {

            return _visibility;
        }

        set
        {
            _visibility = value;
            OnPropertyChanged();
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged([CallerMemberName] string PropertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(PropertyName));
    }
}

For more detail please refer Data binding in depth official document.

Thanks, but it working fine when application loaded and not working when the Visibility value changed dynamically at run-time. I have set mode as TwoWay and UpdateSourceTrigger as PropertyChanged in xaml and RaisePropertyChanged() used for Visibility property in ViewModel class. — Kanniyappan P, Oct 26 '20 at 06:43
You need implement `INotifyPropertyChanged` interface for ViewModel class — Nico Zhu, Oct 26 '20 at 06:57

How to bind two different class properties in DataTemplate

2 Answers2