将项目添加到列表框选定项目的集合

Question

我的窗口中有两个列表框。第一个列表框“all_styles”显示集合中的样式，第二个列表框“Style_subjects”显示第一个列表框中所选样式的集合中的主题。到目前为止一切顺利！

我想引入一个按钮来为当前选定的样式添加新主题。有没有办法将按钮绑定到列表框的选定样式并将新主题添加到绑定的选择中？这是我当前的代码：

xaml：

<Window x:Class="QuickSlide_2._0.Window1"
    x:Name="load_style"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Load_style" Height="300" Width="300" MinHeight="720" MinWidth="1280" WindowStyle="None" AllowsTransparency="True" Background="#B0000000" AllowDrop="True" WindowStartupLocation="CenterScreen" ShowInTaskbar="False">
<Grid>
    <Button Content="Close" Height="23" HorizontalAlignment="Left" Margin="1081,65,0,0" Name="close" VerticalAlignment="Top" Width="120" Click="close_Click" />
    <Button Content="New style" Height="23" HorizontalAlignment="Left" Margin="326,65,0,0" Name="New_style" VerticalAlignment="Top" Width="120" Click="New_style_Click"/>
    <Button Content="New subject" Height="23" HorizontalAlignment="Left" Margin="704,65,0,0" Name="New_subject" VerticalAlignment="Top" Width="120" Click="New_subject_Click" />
    <ListBox Height="146" HorizontalAlignment="Left" Margin="74,111,0,0" x:Name="all_styles" VerticalAlignment="Top" Width="209" ItemsSource="{Binding styles, ElementName=load_style}" SelectedIndex="0">
        <ListBox.ItemTemplate>
            <DataTemplate>
                <TextBlock Text="{Binding name}" />
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>
    <ListBox Height="314" HorizontalAlignment="Left" Margin="74,297,0,0" Name="Style_subjects" VerticalAlignment="Top" Width="209" ItemsSource="{Binding SelectedItem.subjects, ElementName=all_styles}" SelectedIndex="0">
        <ListBox.ItemTemplate>
            <DataTemplate>
                <TextBlock Text="{Binding name}" />
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>
</Grid>

和代码：

public class subject
{
    public string name {get; set;}
    public subject(string name)
    {
        this.name = name;
    }
}


public class style
{
    public string name { get; set; }
    public ObservableCollection<subject> subjects {get; set;}

    public style(string name)
    {
        this.name = name;
        subjects = new ObservableCollection<subject>();
    }
}


public partial class Window1 : Window
{
    public ObservableCollection<style> styles {get; set;}
    public Window1()
    {
        styles = new ObservableCollection<style>();
        InitializeComponent();

        styles.Add(new style("test"));
        styles[0].subjects.Add(new subject("item"));
   }

    private void close_Click(object sender, RoutedEventArgs e)
    {
        this.Close();
    }

    private void New_style_Click(object sender, RoutedEventArgs e)
    {
        styles.Add(new style("new_style"));           
    }

    private void New_subject_Click(object sender, RoutedEventArgs e)
    {
        // this next line is probably not correct....
        this.add(new subject("new_subject"));
    }

}

Answer 1

((style)this.all_styles.SelectedItem).Add(new subject("item"));