如何将数据绑定到控件的可见性属性

本文关键字:可见性 属性 控件 数据绑定 | 更新日期: 2023-09-27 18:33:02

我知道控件的 Visibility 属性不能像其他属性那样绑定到数据。它需要某种转换器(?在尝试实现这个问题的解决方案时,我遇到了一个编译器错误,上面写着:The resource "BoolToVisible" could not be resolved .我猜我必须创建一个名为BoolToVisibleResourceKey,我只是不知道怎么做。

请求有人向我展示绑定到控件的可见性属性的正确方法。

*我添加此控件的控件是一个单选按钮。* 我在数据模型中有一个用于isVisiblebool 属性,该属性将绑定到此单选按钮。

数据模型属性:

private bool _isVisible = true;
public bool IsVisible
{
       get { return _isVisible; }
       set
       {
           _isVisible = value;
           NotifyPropertyChange(() => IsVisible);
       }
}

XAML:

<RadioButton Visibility="{Binding DataModel.IsVisible,Converter={StaticResource ResourceKey=BoolToVisible},RelativeSource={RelativeSource TemplatedParent}}" ... />

谢谢。

如何将数据绑定到控件的可见性属性

2 个例子:

第一个使用转换器,如问题中所述:

  public class BooleanToVisibilityConverter : IValueConverter 
  {
     public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
     {            
         if (value == null || !(value is bool)) 
             return Binding.DoNothing;
         return (bool)value ? Visibility.Visible : Visibility.Collapsed; 
     }
     public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
     {
         return value;
     }
 }

在 XAML 中:

<Window x:Class="Stackoverflow.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525"
    xmlns:local="clr-namespace:Stackoverflow"
    >
<Window.Resources>
    <local:BooleanToVisibilityConverter x:Key="booleanToVisibiltyConverter"/>
</Window.Resources>
<Grid>
    <Button Visibility="{Binding IsSomeThing,Converter={StaticResource booleanToVisibiltyConverter}}"/>        
</Grid>

第二种:

在数据上下文中,您可以真正持有可见性属性

.cs:

    private Visibility _myControlVisibility;
    public Visibility MyControlVisibility
    {
        get { return _myControlVisibility; }
        set { _myControlVisibility = value; }
    }

XAML :

    <Button Visibility="{Binding MyControlVisibility}"/>        

您可以将可见性与属性绑定,您只需要具有可见性的依赖属性字段,如下所示:

    Public Property MyVisibility As Windows.Visibility
    Get
        Return GetValue(MyVisibilityProperty)
    End Get
    Set(ByVal value As Windows.Visibility)
        SetValue(MyVisibilityProperty, value)
    End Set
End Property
Public Shared ReadOnly MyVisibilityProperty As DependencyProperty = _
                       DependencyProperty.Register("MyVisibility", _
                       GetType(Windows.Visibility), GetType(MyWindow), _
                       New PropertyMetadata(Nothing))

然后像往常一样进行绑定(代码在 VB 中)。

请记住,在新的属性元数据中,您可以为对象设置初始状态,例如:

 Public Shared ReadOnly MyVisibilityProperty As DependencyProperty = _
                       DependencyProperty.Register("MyVisibility", _
                       GetType(Windows.Visibility), GetType(MyWindow), _
                       New PropertyMetadata(Windows.Visibility.Hidden))