如何绑定查找组合框？ [英] How do I bind a lookup combobox?

问题描述

我WPF4组合框下拉列表中错误地显示我的EF4实体的类名。下面是相关XAML：

My WPF4 combobox dropdown list is incorrectly displaying the class name of my EF4 entity. Here is the relevant XAML:

<Window.Resources>
    <CollectionViewSource x:Key="myEntitiesViewSource"/>
</Window.Resources>

<ComboBox ItemsSource="{Binding Source={StaticResource myEntitiesViewSource}}" DisplayMemberPath="CategoryDescription" SelectedValuePath="CategoryID" />

下面是我Window_Loaded事件中的code：

Here is the code in my Window_Loaded event:

var categoryList = from p in _context.Categories
                  orderby p.CategoryNumber
                  select p;

System.Windows.Data.CollectionViewSource myEntitiesViewSource = ((System.Windows.Data.CollectionViewSource)(this.FindResource("myEntitiesViewSource")));
// Load data by setting the CollectionViewSource.Source property:
myEntitiesViewSource.Source = categoryList;

我的数据库有许多与一个连接表名为ProjectCategories项目和类别之间的一对多关系。类别实体被自动地作为一个单一实体来重新present两个数据库表中创建：

My database has a many to many relationship between Projects and Categories with a join table called ProjectCategories. The Categories entity was automagically created as a single entity to represent two database tables:

1）含有一个ID分类的查找表，CategoryDe​​scription和CategoryNumber以及

1) the lookup table of Categories containing an ID, CategoryDescription and CategoryNumber and

2）连接表ProjectCategories 只包含两个字段 - 的ID从表中的项目和类别。实体模型住在从我的WPF窗口一个单独的项目。

2) the join table ProjectCategories containing only two fields - the IDs from the tables Projects and Categories. The entity model lives in a separate project from my WPF window.

我的目标是让用户选择从下拉列表中CategoryDe​​scription，然后单击添加类别按钮将选定的类别添加到ProjectCategories的单独列表。随着当前code我看到在组合框中文本区域多次正确CategoryDe​​scription但下拉列表中只显示实体类名称类别（按它pceded $ P $的命名空间）！

My goal is to allow the user to select a CategoryDescription from the dropdown list, then click an Add Category button to add the selected Category to a separate list of ProjectCategories. With the current code I see the correct CategoryDescription in the combobox text area but the dropdown list displays only the entity class name Categories (preceded by it's namespace) multiple times!

如何我正确地使这个简单的查找组合框的绑定，并显示CategoryDe​​scriptions列表和类别ID的SelectedValue的注意：我会接受一个code唯一方法留下了CollectionViewSource中XAML如果可能的话。

How do I make this simple lookup combobox bind correctly and display a list of CategoryDescriptions and a SelectedValue of CategoryID? Note: I'd accept a code only approach leaving out the CollectionViewSource in XAML if it's possible.

谢谢！

推荐答案

没关系。我问这个问题，并回答了它自己。有什么错我的code或XAML。 的问题通过使用第三方主题的样式我的控制造成的。一旦我删除了主题组合框结合问题就走了。有关详细信息see这个帖子。

Nevermind. I asked this question and have answered it myself. There was nothing wrong with my code or XAML. The problem was caused by the use of a third party theme to style my controls. Once I removed the theme the combobox binding problem went away. For more details see this post.

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