XAML绑定未更新

本文关键字：更新 绑定 XAML | 更新日期: 2023-09-27 18:15:00

我有一个GridView组件，它持有我的项目。当一个项目被选中时，我希望控件在它上面弹出，允许您编辑或删除项目。以下是我用于项目的DataTemplate:

<Grid Height="200" Width="200">
    <Grid.RowDefinitions>
        <RowDefinition Height="*"/>
        <RowDefinition Height="Auto"/>
    </Grid.RowDefinitions>
    <Rectangle Grid.Row="0" Fill="White"/>
    <TextBlock Grid.Row="0" VerticalAlignment="Center" HorizontalAlignment="Center" Text="No preview image" FontSize="18" Foreground="{ThemeResource TextBoxDisabledBorderThemeBrush}"/>
    <Image Style="{StaticResource ProjectCoverImageStyle}" Grid.Row="0"/>
    <TextBlock Style="{StaticResource ProjectTitleStyle}" Text="{Binding Title}" Grid.Row="1"/>
    <!--The controls for editing and deleting. Show only when project is selected.-->
    <Grid x:Name="ControlsGrid" Visibility="{Binding IsCurrent, Converter={StaticResource VisibilityConverter}}">
        <Rectangle Grid.Row="0" Fill="Gray" Opacity="0.5"/>
        <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center" Orientation="Horizontal">
            <Border Style="{StaticResource RoundButtonStyle}">
                <Image Source="/Assets/Icons/Edit.png" Style="{StaticResource RoundButtonIconStyle}"/>
            </Border>
            <Border Style="{StaticResource RoundButtonStyle}" Tapped="Delete_Project">
                <Image Source="/Assets/Icons/Delete.png" Style="{StaticResource RoundButtonIconStyle}"/>
            </Border>
        </StackPanel>
    </Grid>
</Grid>

我像这样定义转换器:

<local:VisibilityConverter x:Key="VisibilityConverter"/>

visible converter是一个类:

public class VisibilityConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, string language)
    {
        bool visibility = (bool)value;
        return visibility ? Visibility.Visible : Visibility.Collapsed;
    }
    public object ConvertBack(object value, Type targetType, object parameter, string language)
    {
        Visibility visibility = (Visibility)value;
        return (visibility == Visibility.Visible);
    }
}

在GridView中选择一个项目运行如下:

private void Projects_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    if (e.AddedItems.Count < 1)
        return;
    foreach (Project project in ProjectsGridView.Items)
    {
        if (ProjectsGridView.SelectedItem != project)
            project.IsCurrent = false;
        else
        {
            project.IsCurrent = true;
            ViewModel.CurrentProject = ViewModel.Projects[ProjectsGridView.SelectedIndex];
        }
    }
}

如果我手动设置IsCurrent为true，它工作得很好。但是，当选择/取消选择项目时，它不会更新。我的代码正确地设置了IsCurrent，但是绑定似乎没有更新。还有什么需要做的吗?

XAML绑定未更新

如果我手动设置IsCurrent为true，它会正常工作

要通知xaml这样的更改，持有IsCurrent的类需要坚持INotifyPropertyChange, IsCurrent的setter需要启动属性更改通知。然后，它将以手动方式和编程方式工作。

相关文章：