如何在UWP XAML中向listboxitem添加功能按钮

Question

I have a UWP C# app with a ListBox. I set the ListBox ItemContainerStyle property to a style in a resource. I am stuck trying to add a button to the ControlTemplate within the style. I don't know where to add the Clicked or tapped event handler.

I converted the code to use a UserControl added directly to the list and it works great except that the VisualStateManager doesn't work in the UserControl.

So I can get a functioning button with code-behind for a UserControl and I can get the VisualStateManager to work and handle my custom visualization for the ListBoxItem selections, but I can't get visual states as well as a functioning button.

I'm not sure what code to show here because like I said, everything but the button works fine with a style and everything works fine with a user control except for visual state handling.

I have read all the questions I can find about this and the closest I can come is to having a handler function for the button but no one says what class to add it to; they just show the function alone not in any context. And visual state handling always seems to require the developer to detect mouse over, selection, etc..., states to be handled in code with a handler for each state to detect and then a call to GoToState to get the visual state manager to do its thing. There has got to be a way to do this without all of these gyrations and extra and seemingly redundant code.

[Update]

I am currently using a style for the ListBoxItem by setting ItemContainerStyle. Additionally, I am trying to bind the Command parameter of the newly added Button. It doesn't work. Here's the XAML for the style, showing just the important parts (because it all works as expected except for the button). This shows the two text boxes and the button. It is important to note that the binding of the Text properties of the TextBox elements works fine and the text shows up exactly as expected. this makes me want to assume that the binding source and path stuff is all set correctly. But yet again, I an foiled because the Command binding isn't working and no errors are reported at build or run time:

<StackPanel Background="Transparent" Margin="0,0,0,0">
    <TextBlock FontSize="22" TextWrapping="Wrap" FontWeight="SemiLight" x:Name="Title" Text="{Binding Title}" Margin="12,4,24,6" Visibility="{Binding Title, Converter={StaticResource StringToVisibiltyConverter}}" Foreground="{Binding color}"/>
    <TextBlock TextWrapping="Wrap" Visibility="{Binding SubTitle, Converter={StaticResource StringToVisibiltyConverter}}" x:Name="Subtitle" Text="{Binding SubTitle}" Margin="12,-6,24,6" Opacity="0.8" Foreground="{Binding color}"/>
    <Button Command="{Binding ClickCommand}" CommandParameter="x">X</Button>
</StackPanel>

Here is the code for the object that I add to the ListBox:

public class MultilineListboxItem : Object
{
    public MultilineListboxItem() { ClickCommand = new _ClickCommand(); }

    public string Title { get; set; }
    public string SubTitle { get; set; }
    public string Original { get; set; }
    public override string ToString() { return Original; }
    public SolidColorBrush color { get; set; }

    _ClickCommand ClickCommand;
}

And of course, the _ClickCommand class definition:

public class _ClickCommand : ICommand
{
    public void Execute(object parameter)
    {
        Diagnostics.AppendDiagnostic( "derf" );
    }


    public bool CanExecute(object parameter)
    {
        Diagnostics.AppendDiagnostic( "derf" );
        return true;
    }

    public event EventHandler CanExecuteChanged;
}

Those are my own diagnostic reporting functions, not something in C# or WinRT.

Now that I ma back to using a style to define the look of the list items, the visual states are all working as expected.

Answer 1

Try to change ClickCommand to a public property.

• The properties you use as binding source properties for a binding must be public properties of your class. Explicitly defined interface properties cannot be accessed for binding purposes, nor can protected, private, internal, or virtual properties that have no base implementation.
• You cannot bind to public fields.

references:

• https://stackoverflow.com/a/19704292/3869284
• https://msdn.microsoft.com/en-us/library/ms743643.aspx?f=255&MSPPError=-2147217396