Question

I want to bind one data to several controls. Is there some logical control in WPF to achieve this?
For example i have a Grid

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition />
    </Grid.ColumnDefinitions>

    <TextBlock Text="{Binding Name}" />
    <Button Grid.Column="1" Grid.RowSpan="2" IsEnabled="{Binding IsSimulationRunning}" />
    <controls:PlayerControl Grid.Row="1" IsEnabled="{Binding IsLoaded}" />
</Grid>

and I want to bind TextBlock to one data and Button and PlayerControl to another, like this:

<Container DataContext="{Binding Object2}">
    <Button IsEnabled="{Binding IsSimulationRunning}" />
    <controls:PlayerControl IsEnabled="{Binding IsLoaded}" />
</Container>

How can I do this in the best way?

Answer 1

The binding binds to the DataContext of the element containing the dependency property. And you can bind the DataContext to the underlying view model:

<TextBlock DataContext="{Binding Object1}" Text="{Binding Name}" />
<Button Grid.Column="1" Grid.RowSpan="2" 
    DataContext="{Binding Object2}" IsEnabled="{Binding IsSimulationRunning}" />
<controls:PlayerControl Grid.Row="1" 
    DataContext="{Binding Object2}" IsEnabled="{Binding IsLoaded}" />

If your view model looks like this:

public class PlayerViewModel {        
    public TrackViewModel Object1 { get; set; }
    public PlaybackViewModel Object2 { get; set; }
}
public class TrackViewModel { public string Name { get; set; } }
public class PlaybackViewModel { 
    public bool IsLoaded { get; set; } 
    public bool IsSimulationRunning { get; set; }
}

In this case you could bind to the objects directly. The main point is that you need to have the two objects in 1 common view model.

<TextBlock Text="{Binding Path=Object1.Name}" />
<Button Grid.Column="1" Grid.RowSpan="2" IsEnabled="{Binding Path=Object2.IsSimulationRunning}" />
<controls:PlayerControl Grid.Row="1" IsEnabled="{Binding Path=Object2.IsLoaded}" />