如何获得项目从CollectionViewSource算什么? [英] How to get Items count from CollectionViewSource?
问题描述
我使用CollectionViewSource来过滤列表框显示的记录。该XAML如下
I am using CollectionViewSource to filter the records displayed in a ListBox. The xaml follows.
<Window x:Class="WPFStarter.ListBoxItemsFilter.ListBoxFilterUsingCollectionViewSource"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Name="userControl"
Title="ListBoxFilterUsingCollectionViewSource" Height="300" Width="300">
<Window.Resources>
<CollectionViewSource Source="{Binding ElementName=userControl, Path=DataContext.Items}"
x:Key="cvs" Filter="CollectionViewSource_Filter"/>
</Window.Resources>
<StackPanel Orientation="Vertical">
<TextBox x:Name="txtSearch" TextChanged="txtSearch_TextChanged"/>
<TextBlock x:Name="txtSummary" Grid.Column="0" HorizontalAlignment="Right" VerticalAlignment="Bottom" FontSize="8"></TextBlock>
<ListBox ItemsSource="{Binding Source={StaticResource cvs}}" DisplayMemberPath="First"/>
</StackPanel>
</Window>
和这里是我的代码behing(请不要;介意这款代号背后,真正的。应用程序,我现在用的是最好的MVVM为这种情况)
And here is my code-behing ( please don;t mind this code-behind, in the real application i am using the best of MVVM for this scenario).
public partial class ListBoxFilterUsingCollectionViewSource : Window
{
private string _text="";
private readonly CollectionViewSource _viewSource;
public ListBoxFilterUsingCollectionViewSource()
{
InitializeComponent();
_viewSource = this.FindResource("cvs") as CollectionViewSource;
}
private void CollectionViewSource_Filter(object sender, FilterEventArgs e)
{
var character = e.Item as Character;
e.Accepted = character != null && character.First.ToLower().Contains(_text.ToLower());
}
private void txtSearch_TextChanged(object sender, TextChangedEventArgs e)
{
_text = txtSearch.Text;
_viewSource.View.Refresh();
SetSummary();
}
private void SetSummary()
{
var initialCount = 10; //HELP????
var filteredCount = 10; //HELP????
txtSummary.Text = String.Format("{0} of {1}", filteredCount, initialCount);
}
}
问:
我需要写SetSummary的方法,其特征在于,我可以得到initialCount,并从CollectionViewSource对象filteredCount的帮助。
QUESTION: I Need help in writing the "SetSummary" method, wherein i can get the "initialCount" and the "filteredCount" from CollectionViewSource object.
感谢您的关注。
推荐答案
源收集和的CollectionView都实现IEnumerable让你随时可以遍历他们指望有多少是在其中。但我只想建议这样做,如果你有你作为源的实际征收的访问权限。
The source collection and collectionview both implements IEnumerable so you can always iterate over them and count how many are in them. But I would only recommend doing this if you have no access to the actual collection you used as source.
private void SetSummary()
{
int initialCount = 0;
foreach(var item in _viewSource.View.SourceCollection)
{
initialCount++;
}
int filteredCount = 0;
foreach (var item in _viewSource.View)
{
filteredCount++;
}
}
这篇关于如何获得项目从CollectionViewSource算什么?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!