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BoolToVisible
的ResourceKey
,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isVisible
的 bool
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。
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))