我遇到了一些需要帮助的问题。我想将视图模型中的可见性属性绑定到xaml元素,这样我只需更改viewmodel中的值就可以进行一些直观的更改(在这种情况下可以折叠或显示)。
我得到了这个xaml
<Window x:Class="PampelMuse.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:welcome="clr-namespace:PampelMuse.Views.Welcome"
xmlns:backend="clr-namespace:PampelMuse.Views.Backend"
xmlns:pampelMuse="clr-namespace:PampelMuse" xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"
Title="PampelMuse" Height="670" Width="864">
<Grid>
<Image HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Source="Resources/Images/Backgrounds/4.jpg" Stretch="UniformToFill" />
<welcome:WelcomeScreen x:Name="UIWelcome" HorizontalAlignment="Center" VerticalAlignment="Center" Visibility="{Binding ElementName=UiWelcomeVisibility}" />
<backend:BackendUI x:Name="UIBackend" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Visibility="{Binding ElementName=UiBackendVisibility}" />
</Grid>
您可以看到的可见性绑定到UIModel中的属性 UiWelcomeVisibility 和 UiBackendVisibility 。这些属性现在定义如下:
public partial class MainWindow : Window
{
private ViewModel.ViewModel ViewModel = PampelMuse.ViewModel.ViewModel.GetInstance();
public MainWindow()
{
InitializeComponent();
DataContext = ViewModel; // Setting the data context what effects all the xaml elements in this component too, including UIWelcome and BackendUI
ViewModel.UIModel.UiBackendVisibility = Visibility.Collapsed;
}
ViewModel:
public class ViewModel
{
private static ViewModel instance = new ViewModel();
public UIModel UIModel = UIModel.GetInstance();
public static ViewModel GetInstance()
{
return instance;
}
}
和UIModel:
public class UIModel
{
private static UIModel instance = new UIModel();
public Visibility UiWelcomeVisibility { get; set; }
public Visibility UiBackendVisibility { get; set; }
public static UIModel GetInstance()
{
return instance;
}
}
我只是没有看到任何编码错误(事实上我没有在运行时获得)但是Ueodel的UiBackendVisibility不会改变BackendUI-visibility-property。
有什么想法吗?谢谢到目前为止。
答案 0 :(得分:1)
你正在做错绑定。 Visibility="{Binding ElementName=UiWelcomeVisibility}"
将元素的可见性设置为等于名为“UiWelcomeVisibility”的另一个可视元素。这有两个问题:
Visibility
属性的有效值。你想要的是数据绑定到viewmodel。假设您已将DataContext
设置为viewmodel,只需使用
<welcome:WelcomeScreen ... Visibility="{Binding UiWelcomeVisibility}" />