フィルタ処理

The ListView control supports filtering using the DataCollection library.

DataCollection implements the IDataCollection interface to support filtering, which enables you to filter data using the FilterAsync method of the IDataCollectionEx class. This method calls the filtering operation in the collection view and refines data according to the user requirements without including other data that can be repetitive or irrelevant.

The following code implements filtering in the ListView control using the FilterAsync method.

XAML
C#

Tab Caption

<Grid x:Name="LayoutRoot">
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
        <RowDefinition Height="*" />
    </Grid.RowDefinitions>

    <c1:C1TextBox x:Name="txtFilter" TextChanged="C1TextBox_TextChanged"  Placeholder="Type here to filter" 
                  Grid.Row="0" Margin="10 0 0 10" Width="300" HorizontalAlignment="Left"/>

    <c1:C1ListView x:Name="listView" Grid.Row="1" Grid.ColumnSpan="4" SelectionMode="Single" DisplayMemberPath="Name"
                   Margin="10 0 10 10" ItemHeight="30" SelectedBackground="#99c9ef" />

</Grid>

Tab Caption

string currentFilterValue;
System.Threading.SemaphoreSlim filterSemaphore;
public MainWindow()
{
    InitializeComponent();
    // データソースに連結します。

    filterSemaphore = new System.Threading.SemaphoreSlim(1);
    txtFilter.Text = "";
    listView.ItemsSource = Person.Generate(100);
}
// FilterAsync メソッドでグループ化を追加します。
private async void C1TextBox_TextChanged(object sender, TextChangedEventArgs e)
{
    try
    {
        var filter = txtFilter.Text;
        currentFilterValue = filter;
        await Task.Delay(400);
        await filterSemaphore.WaitAsync();
        if (currentFilterValue == filter)
        {
            await listView.DataCollection.FilterAsync("Name", FilterOperation.Contains, filter);
        }
    }
    finally
    {
        filterSemaphore.Release();
    }
}