Question

I am working with a WPF control that I created and I am trying to only show certain rows of my list by values of a property. An example is the following, I have a User class that holds a property of Active. How do I tell the .xaml that the list should only show the people that are Active?

Right now I am basically using linq to generate a new list and hand it to the listview based on what I want. However, I would rather just hand the ListView my entire list and let it do the work for me.

Here is my ListView code.

<ListView ItemsSource="{Binding}" DataContext="{Binding }" >
     <ListView.View>
          <GridView>
               <GridViewColumn>
                    <GridViewColumn.CellTemplate>
                         <DataTemplate>
                              <StackPanel>
                                   <TextBlock Text="{Binding Index}"/>
                                   <TextBlock Text=". " />
                                   <TextBlock Text="{Binding FirstName}" />
                                   <TextBlock Text="{Binding LastName}" />
                              </StackPanel>
                         </DataTemplate>
                    </GridViewColumn.CellTemplate>
               </GridViewColumn>
          </GridView>
     </ListView.View>
</ListView>

Answer 1

You’ll need some code behind to add a filter:

See: WPF filtering

ICollectionView view = CollectionViewSource.GetDefaultView(lstMovies.ItemsSource);  
view.Filter = null;  
view.Filter = new Predicate<object>(FilterMovieItem);  


private bool FilterMovieItem(object obj)  
{  
    MovieItem item = obj as MovieItem;  
    if (item == null) return false;  

    string textFilter = txtFilter.Text;  

    if (textFilter.Trim().Length == 0) return true; // the filter is empty - pass all items  

    // apply the filter  
    if (item.MovieName.ToLower().Contains(textFilter.ToLower())) return true;  
    return false;  
}