基于布尔值的 ListView 项目可见性

Question

我正在尝试根据输入文本过滤 ListView 项目，并且由于选择被删除，我正在尝试根据布尔值将可见性设置为不可见（我希望这不会删除项目的选择）

我使用了一些较早的帖子来创建此代码，但我无法弄清楚它为什么不起作用：

 <ListView x:Name="osebe_listView" Margin="0,0,40,0"  SelectionMode="Multiple"  SelectionChanged="osebe_listView_SelectionChanged" BorderThickness="0" ScrollViewer.HorizontalScrollBarVisibility="Hidden">

            <ListView.Resources>

                <Style TargetType="{x:Type ListViewItem}">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding visible}" Value="False">
                            <Setter Property="Visibility" Value="Hidden"/>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
                <Style TargetType="{x:Type GridViewColumnHeader}">
                    <Setter Property="Background" Value="#1AFFFFFF" />
                    <Setter Property="BorderThickness" Value="0"/>
                </Style>
                <Style TargetType="{x:Type ColumnDefinition}">
                    <Setter Property="Width" Value="10"/>
                </Style>

            </ListView.Resources>

            <ListView.View>
                <GridView>
                    <GridViewColumn Header="Naziv podjetja" DisplayMemberBinding="{Binding nazivPodjetja}"/>
                    <GridViewColumn Header="Ime" DisplayMemberBinding="{Binding ime}" Width="25"/>
                    <GridViewColumn Header="Priimek" DisplayMemberBinding="{Binding priimek}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="Naslov" DisplayMemberBinding="{Binding naslov}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="Pošta" DisplayMemberBinding="{Binding posta}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="Mobilna številka" DisplayMemberBinding="{Binding mobilnaSt}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="Stacionarna številka" DisplayMemberBinding="{Binding stacionarnaSt}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="E-naslov" DisplayMemberBinding="{Binding eMail}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                    <GridViewColumn Header="Skupina" DisplayMemberBinding="{Binding skupina}" Width="{Binding ActualWidth, ElementName=helperField}"/>
                </GridView>
            </ListView.View>
        </ListView>

文本过滤方法（效果很好）：

  private void isci_tb_TextChanged(object sender, TextChangedEventArgs e)
    {
        try
        {
            if (isci_tb.Text == "search") return;
            string s = isci_tb.Text;
            if (isci_tb.Text == "")
            {
                foreach (Oseba o in seznamOseb)
                {
                    //osebe_listView.Items.Add(o);
                    o.visible = true;
                }
            }
            //else
            //{
          //  osebe_listView.Items.Clear();
                foreach (Oseba o in seznamOseb)
                {
                    if(! (contejns(o.ime, s) || contejns(o.priimek, s) || contejns(o.mobilnaSt.ToString(), s) || contejns(o.posta, s) || contejns(o.nazivPodjetja, s) || contejns(o.stacionarnaSt.ToString(), s) || contejns(o.naslov, s) || contejns(o.eMail, s)))
                    {
                    o.visible = false;
                    }
                }
            //}
        }
        catch { }
    }

我找到了code here

请注意，我没有使用任何数据绑定。我错过了什么？

Answer 1

确保Oseba 类实现INotifyPropertyChanged 接口并在visible 属性的设置器中引发PropertyChanged 事件：

public class Oseba : INotifyPropertyChanged
{
    private bool _isVisible;
    public bool visible
    {
        get { return _isVisible; }
        set { _isVisible = value; NotifyPropertyChanged("visible"); }
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void NotifyPropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }
}

这是动态触发ListViewItem 样式的数据触发器所必需的。

您还应该使用DataTrigger 将ListView 的ItemContainerStyle 属性设置为您的自定义样式：

<ListView x:Name="osebe_listView" Margin="0,0,40,0"  SelectionMode="Multiple"  SelectionChanged="osebe_listView_SelectionChanged" BorderThickness="0" ScrollViewer.HorizontalScrollBarVisibility="Hidden">
    <ListView.ItemContainerStyle>
        <Style TargetType="{x:Type ListViewItem}">
            <Style.Triggers>
                <DataTrigger Binding="{Binding visible}" Value="False">
                    <Setter Property="Visibility" Value="Hidden"/>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </ListView.ItemContainerStyle>
    <ListView.Resources>
        <Style TargetType="{x:Type GridViewColumnHeader}">
            <Setter Property="Background" Value="#1AFFFFFF" />
            <Setter Property="BorderThickness" Value="0"/>
        </Style>
        <Style TargetType="{x:Type ColumnDefinition}">
            <Setter Property="Width" Value="10"/>
        </Style>
    </ListView.Resources>

    <ListView.View>
        <GridView>
            <GridViewColumn Header="Naziv podjetja" DisplayMemberBinding="{Binding nazivPodjetja}"/>
            <GridViewColumn Header="Ime" DisplayMemberBinding="{Binding ime}" Width="25"/>
            <GridViewColumn Header="Priimek" DisplayMemberBinding="{Binding priimek}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="Naslov" DisplayMemberBinding="{Binding naslov}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="Pošta" DisplayMemberBinding="{Binding posta}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="Mobilna številka" DisplayMemberBinding="{Binding mobilnaSt}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="Stacionarna številka" DisplayMemberBinding="{Binding stacionarnaSt}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="E-naslov" DisplayMemberBinding="{Binding eMail}" Width="{Binding ActualWidth, ElementName=helperField}"/>
            <GridViewColumn Header="Skupina" DisplayMemberBinding="{Binding skupina}" Width="{Binding ActualWidth, ElementName=helperField}"/>
        </GridView>
    </ListView.View>
</ListView>