將項添加到列表框的選定項的集合

Question

我的窗口中有兩個列表框。第一個列表框「all_styles」顯示集合中的樣式，第二個列表框「Style_subjects」顯示第一個列表框中所選樣式的集合中的主題。到現在爲止還挺好！

我想介紹一個按鈕來爲當前所選樣式添加一個新主題。有沒有辦法將按鈕綁定到列表框的選定樣式並將新主題添加到綁定選擇中？這裏是我當前的代碼：

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> 

，代碼：

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"));