Question

Hej，

我有一个ListBox绑定到ObservableCollection，现在我正在尝试实现搜索/过滤功能。但它不起作用......尝试了一切:(

下载我的ListBox的图片http://i.imgur.com/el8KF3T.png

Ok得到了解决方案，感谢Maximus的Link。我已经更新了我的代码。

并且我到目前为止尝试了我的.xaml代码

 <ListBox Name="lstWarning" Margin="-14,3,-31,-30">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <Canvas Height="62" Width="582">
                <Label Foreground="#FFA8A4A4" FontFamily="{DynamicResource HeaderFontFamily}" FontSize="11" Content="{Binding DirName}" Canvas.Left="39" Canvas.Top="23"/>
                <Label Foreground="#FFA8A4A4" FontFamily="{DynamicResource HeaderFontFamily}" FontSize="11" Content="{Binding CreationDate}" Canvas.Left="39" Canvas.Top="40"/>
                <Label Foreground="White" FontFamily="{DynamicResource HeaderFontFamily}" FontSize="14" Content="{Binding FileName}" Canvas.Left="39" Canvas.Top="4"/>
                <Label Foreground="#FFA8A4A4" FontFamily="{DynamicResource HeaderFontFamily}" FontSize="11" Content="{Binding Extension}" Canvas.Left="224" Canvas.Top="40"/>
                <Label Foreground="#FFA8A4A4" FontFamily="{DynamicResource HeaderFontFamily}" FontSize="11" Content="{Binding FileSize}" Canvas.Left="155" Canvas.Top="40"/>
                <Image Source="{Binding StatusImage}" Width="30" Height="30" Canvas.Left="10" Canvas.Top="6" Stretch="Fill"/>
            </Canvas>
        </DataTemplate>
    </ListBox.ItemTemplate>
 </ListBox>

如果在TextChanged事件中完成了什么

private void cmdSearchWarnings_TextChanged(object sender, System.Windows.Controls.TextChangedEventArgs e) {

        CollectionView cv = (CollectionView)CollectionViewSource.GetDefaultView(lstWarning.ItemsSource);
        if (!string.IsNullOrEmpty(txtSearchWarnings.Text)) {


            if (isFilter) {
                cv.Filter = null;
                isFilter = false;   
            }
            else {
                cv.Filter = new Predicate<object>(FilterByFileName);
                isFilter = true;
            }
        }
        else {
            cv.Filter = null;
            isFilter = false;
        }
    }

    private bool FilterByFileName(object _warningObj) {
        if (_warningList != null) {

            if (!string.IsNullOrEmpty(txtSearchWarnings.Text)) {
                var warning = _warningObj as WarningItem;
                return warning.FileName.Trim().Contains(txtSearchWarnings.Text);
            }
        }
        return false;
    }

继承我的WarningItem类代码：

public class WarningItem
{
    public string FullPath { get; set; }

    public string DirName { get; set; }

    public string FileName { get; set; }

    public string FileSize { get; set; }

    public string CreationDate { get; set; }

    public string Extension { get; set; }

    public Uri StatusImage { get; set; }
}

Answer 1

我正在粘贴一个简单的例子，但类似的内容涵盖了无数次你需要深入研究SO。以下示例检查集合名称是否包含搜索单词的元素。

private ObservableCollection<string> _names = new ObservableCollection<string>()
    {
        "Isabel", "Michal"
    };

    public ObservableCollection<string> Names
    {
        get { return _names; }
        set { _names = value; }
    }

    private ICollectionView View;

    public MainWindow()
    {
        InitializeComponent();
        ListBox.ItemsSource = Names;
        View = CollectionViewSource.GetDefaultView(Names);
    }

    private void TextBoxBase_OnTextChanged(object sender, TextChangedEventArgs e)
    {
        View.Filter = x => x.ToString().ToLower().Contains(((TextBox)sender).Text.ToLower());
    }

不需要在TextBoxChanged事件中调用 CollectionViewSource.GetDefaultView（Names），因为collectionView被检索一次并保持引用。看看here。

如果涉及MVVM模式，则不应使用代码隐藏而不是

<TextBox TextChanged="TextBoxBase_OnTextChanged"/>

你应该有

  <TextBox Text="{Binding FilterText}">
        <i:Interaction.Triggers>
            <i:EventTrigger EventName="TextChanged">
                <i:InvokeCommandAction Command="{Binding FilterListCommand}"/>
            </i:EventTrigger>
        </i:Interaction.Triggers>
    </TextBox>

RelayCommand

过滤/搜索绑定列表框

1 个答案: