With intention of having 'no code' in code behind file, we often invest lot of time in finding how to invoke a command in your ViewModel whenever a UIElement raises an event. I certainly invested couple of hours googling.. binging for readymade answers. I couldn't find a satisfactory answers (may be I am poor in using right keywords ). But, with help of couple of posts in sites like StackOverflow & MSDN, I arrived at this very simple approach.
Below is my ViewModel which has a collection called Cities which I will be displaying in a ListBox in my View. My ViewModel has a command called ItemSelectedCommand which should be incoked when user double clicks on city.
And here is the XAML
I hope there is no need to explain the code and I hope you enjoyed reading this :)
Below is my ViewModel which has a collection called Cities which I will be displaying in a ListBox in my View. My ViewModel has a command called ItemSelectedCommand which should be incoked when user double clicks on city.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | /// <summary>
/// ViewModel for CityView
/// </summary>
public class CityViewModel : ViewModelBase
{
/// <summary>
/// Command that responds item double click event.
/// </summary>
public DelegateCommand ItemSelectedCommand { get; private set; }
/// <summary>
/// Gets or sets the selected city.
/// </summary>
public string SelectedCity { get; set; }
/// <summary>
/// Gets the list of cities.
/// </summary>
public List<string> Cities { get; private set; }
/// <summary>
/// Initializes new instance of <see cref="CityViewModel"/> class.
/// </summary>
public CityViewModel()
{
ItemSelectedCommand = new DelegateCommand(OnItemSelected);
Cities = new List<string>() { "Bangalore", "New York", "Sydney", "London", "Washington" };
}
/// <summary>
/// This method is executed when user double clicks on a city.
/// </summary>
/// <param name="sender">Unsed Parameter.</param>
private void OnItemSelected(object sender)
{
//Do the processing you need
}
}
|
And here is the XAML
1 2 3 4 5 6 7 8 9 10 11 12 | <ListBox HorizontalAlignment="Center" ItemsSource="{Binding Cities}" SelectedItem="{Binding SelectedCity}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}">
<TextBlock.InputBindings>
<MouseBinding Gesture="LeftDoubleClick"
Command="{Binding RelativeSource={RelativeSource AncestorType=Window}, Path=DataContext.ItemSelectedCommand}"/>
</TextBlock.InputBindings>
</TextBlock>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
|
I hope there is no need to explain the code and I hope you enjoyed reading this :)
