如何在选择/未选择组合框时启用/禁用诸如文本框、标签、文本块等控件?例如,如果选择的索引大于零,则启用控件,否则禁用。如何将控件的IsEnabled属性与组合框选择绑定?
您可以将IsEnabled
绑定到ComboBox的SelectedIndex
属性,并使用IValueConverter
将其转换为布尔值。例如,在XAML中(显示启用Button
):
<ComboBox x:Name="cmbBox" ItemsSource="{Binding Source={StaticResource DataList}}"/>
<Button Grid.Column="1" IsEnabled="{Binding ElementName=cmbBox, Path=SelectedIndex, Converter={StaticResource IndexToBoolConverter}}"/>
那么您还需要一个转换器,例如:
public class IndexToBoolConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if ((int)value > 0)
{
return true;
}
else
{
return false;
}
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
你还需要将 Converter 声明为资源,例如在你的 Window 中。
<local:IndexToBoolConverter x:Key="IndexToBoolConverter"/>
<Grid>
<Grid.Resources>
<Style TargetType="{x:Type Button}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=SelectedItem,
ElementName=TheCombo}"
Value="{x:Null}">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Resources>
<StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
<ComboBox x:Name="TheCombo" Width="100">
<ComboBoxItem>Blah</ComboBoxItem>
<ComboBoxItem>Blah</ComboBoxItem>
<ComboBoxItem>Blah</ComboBoxItem>
</ComboBox>
<Button Content="Click Me" Margin="0,10"/>
</StackPanel>
</Grid>
试试这个
Dispatcher.BeginInvoke(new Action(() =>
{
ToggleButton dropDownButton = GetFirstChildOfType<ToggleButton>(cboMedicos);
if (dropDownButton != null)
{
dropDownButton.IsEnabled = false;
}
}), System.Windows.Threading.DispatcherPriority.Render);
public static T GetFirstChildOfType<T>(DependencyObject dependencyObject) where T : DependencyObject
{
if (dependencyObject == null)
{
return null;
}
for (var i = 0; i < VisualTreeHelper.GetChildrenCount(dependencyObject); i++)
{
var child = VisualTreeHelper.GetChild(dependencyObject, i);
var result = (child as T) ?? GetFirstChildOfType<T>(child);
if (result != null)
{
return result;
}
}
return null;
}
ComboboxSelection
的PropertyChanged
事件中,您需要更新绑定到要启用/禁用的控件的IsEnabled
属性的VM中的某些其他属性。 - Kidiskidvogingogin