我正在尝试创建一个自定义的多值组合框。所以基本上是一个组合框,有一些复选框作为项目。这个想法是,保持整个控件完全可绑定,以便我可以随时重用。
下面是 XAML
<ComboBox x:Class="WpfExtensions.Controls.MultiSelectComboBox"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:WpfExtensions.Controls"
mc:Ignorable="d" d:DesignHeight="23" d:DesignWidth="150">
<ComboBox.Resources>
<local:CheckBoxConverter x:Key="CheckBoxConverter" />
</ComboBox.Resources>
<ComboBox.ItemTemplateSelector>
<local:MultiSelectBoxTemplateSelector>
<local:MultiSelectBoxTemplateSelector.SelectedItemsTemplate>
<DataTemplate>
<TextBlock Text="{Binding Source={RelativeSource Mode=FindAncestor, AncestorType={x:Type local:MultiSelectComboBox}}, Path=SelectedItems, Converter={StaticResource CheckBoxConverter}}" />
</DataTemplate>
</local:MultiSelectBoxTemplateSelector.SelectedItemsTemplate>
<local:MultiSelectBoxTemplateSelector.MultiSelectItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding}" HorizontalAlignment="Stretch"
Checked="CheckBox_Checked" Unchecked="CheckBox_Checked" Indeterminate="CheckBox_Checked" Click="CheckBox_Checked" />
</DataTemplate>
</local:MultiSelectBoxTemplateSelector.MultiSelectItemTemplate>
</local:MultiSelectBoxTemplateSelector>
</ComboBox.ItemTemplateSelector>
</ComboBox>
以及自定义属性"选定项"的代码隐藏
public static readonly DependencyProperty SelectedItemsProperty = DependencyProperty.Register("SelectedItems", typeof(IList), typeof(MultiSelectComboBox));
[Bindable(true)]
public IList SelectedItems
{
get
{
return (IList)GetValue(SelectedItemsProperty);
}
private set
{
SetValue(SelectedItemsProperty, value);
}
}
现在,当我测试项目时,RelativeSource 已正确解析为控件本身,但是路径"SelectedItems"上的绑定失败,调试器指出 RelativeSource 对象上没有这样的路径。
是我搞砸了绑定还是犯了一个完整的逻辑错误?
您正在将 RelativeSource 设置为源,而是像这样设置 RelativeSource 属性:
<TextBlock Text="{Binding Path=SelectedItems, RelativeSource={RelativeSource AncestorType={x:Type local:MultiSelectComboBox}}, Converter={StaticResource CheckBoxConverter}}" />