WPF-如何为ListBox中的每个元素(按钮)触发事件

Question

我想触发元素的事件，它是列表框中的按钮，视图如下。这是一个有32个按钮的列表框。其目的是在0-1和每个元素的触发事件之间切换按钮。

我正在考虑两种解决方案。解决方案之一是为每个按钮设置命令，它有效，但问题是我无法成功捕获selectedItem或selectedIndex，因此即使我知道按钮被切换，但我不知道项目索引。

<ListBox x:Name="lbDirection"
Grid.Row="1"
Grid.Column="1"
SelectionMode="Extended"
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
ScrollViewer.VerticalScrollBarVisibility="Disabled"
Margin="30,26,44,83"
Style="{StaticResource ListBoxHorz}"
ItemContainerStyle="{StaticResource ItemNoBorder}"
SelectedItem="{Binding SelectedLineItem}"
ItemsSource="{Binding ButtonList}"
IsSynchronizedWithCurrentItem="True">
<ListBox.ItemTemplate>
<DataTemplate>
<Button Style="{StaticResource ChangeButton}"
Command="{Binding DataContext.ToggleDirectionCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType= ListBox}}">
<Button.Content>
<TextBlock Text="{Binding BtnText}"
TextDecorations="Underline" />

</Button.Content>
</Button>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>

ViewModel:

public class DigitalIOViewModel : BindableBase
{
public ICommand ToggleDirectionCommand { get; set; }
public ICommand ToggleStateCommand { get; set; }
private ObservableCollection<LineButtons> btnlist;
private LineButtons _selectedLineItem;
public LineButtons SelectedLineItem
{
get { return _selectedLineItem; }
set {
_selectedLineItem=value;
OnPropertyChanged("SelectedLineItem");
}
}
public DigitalIOViewModel()
{
btnlist = new ObservableCollection<LineButtons>();
CreateButtonList();
ToggleDirectionCommand = new RelayCommand(ToggleDirectionAction);
}
private void ToggleDirectionAction()
{
LineButtons selectedLineItem = SelectedLineItem;
int lineIndex=(SelectedLineItem!= null && ButtonList!=null)? ButtonList.IndexOf(SelectedLineItem) : -1; 
if (selectedLineItem.BtnText == "1" && lineIndex == 0)
{
ButtonList[lineIndex] = new LineButtons() { BtnText = "0" };
}
else
ButtonList[lineIndex] = new LineButtons() { BtnText = "1" };
}
public ObservableCollection<LineButtons> ButtonList
{
get { return btnlist; }
set { btnlist = value; OnPropertyChanged("ButtonList"); }
}

public void CreateButtonList()
{
for (int i = 0; i < 32; i++)
{
ButtonList.Add(new LineButtons() { BtnText = "1"});
}
}
}
public class LineButtons : BindableBase
{
private string btnText;
public string BtnText
{
get { return btnText; }
set { btnText = value; OnPropertyChanged("BtnText"); }
}
}

我无法从此代码中获得正确的selectedIndex。第二个解决方案是使用IsSelected/SelectedItem属性而不是按钮命令绑定，我想知道item的按钮命令绑定和列表框的IsSelected属性是否有冲突，所以我们不能同时使用它们，有人能帮我找出哪种是最好的解决方案吗？提前谢谢。

Answer 1

除了Command属性外，您还可以将CommandParameter设置为当前LineButtons项(类名应为单数，集合名称使用复数(：

<ListBox.ItemTemplate>
<DataTemplate>
<Button Style="{StaticResource ChangeButton}"
Command="{Binding DataContext.ToggleDirectionCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType= ListBox}}"
CommandParameter="{Binding}">
<Button.Content>
<TextBlock Text="{Binding BtnText, UpdateSourceTrigger=PropertyChanged}"
TextDecorations="Underline" />

</Button.Content>
</Button>
</DataTemplate>
</ListBox.ItemTemplate>

然后通过访问命令参数获取当前项目，即触发命令的项目：

private void Execute(object commandParameter)
{
var currentLineButton = commandParameter as LineButtons;
...
}