在列表视图中填充组合框列表

问题描述:

这里对WPF非常陌生。我会设置场景: 我有与支出的东西像这样的列表一个ListView:在列表视图中填充组合框列表

  • 费用说明:超市购物
  • 费用日期:2017年2月3日
  • 费用金额:$ 50
  • 费用类型:食品杂货

的费用类型存储在一个单独的表在我的数据库,并通过外键expense_type_id挂钩的费用。

我试图得到没有费用类型的费用列表,并允许用户从选项列表(即费用类型表中的数据)中设置费用类型。

为此,我创建了一个ListView,其中包含费用而没有expense_type_id。

<ListView x:Name="lvAllocation" HorizontalAlignment="Left" Height="475" Margin="0,44,0,0" VerticalAlignment="Top" Width="1308" FontSize="16"> 
    <ListView.View> 
     <GridView> 
      <GridViewColumn Header="Posted" Width="120" DisplayMemberBinding="{Binding ex_posted_date}" /> 
      <GridViewColumn Header="Trans" Width="120" DisplayMemberBinding="{Binding ex_trans_date}" /> 
      <GridViewColumn Header="Description" Width="120" DisplayMemberBinding="{Binding ex_description}" /> 
      <GridViewColumn Header="Amount" Width="120" DisplayMemberBinding="{Binding ex_amount}" /> 
      <GridViewColumn Header="Expense Type" x:Name ="cmbExpenseType" Width="120"> 
       <GridViewColumn.CellTemplate> 
        <DataTemplate> 
         <ComboBox ItemsSource="{Binding Path=IC_NAME }" Width="120" /> 
        </DataTemplate> 
       </GridViewColumn.CellTemplate> 
      </GridViewColumn> 
     </GridView> 
    </ListView.View> 
</ListView> 

上面是详细列表视图的WPF。填充后面的代码是:

Private Sub SetupAllocationTab() 
    'Get list from DB (where there isn't an expense type) 
    Dim queryExceptions = 
     From expense In dataEntities.expenses 
     Where expense.expense_type.ex_type_desc Is Nothing 
     Order By expense.ex_posted_date 
     Select 
      expense.ex_id, 
      expense.ex_type_id, 
      expense.override_ex_type_id, 
      expense.month_id, 
      expense.account_id, 
      expense.ex_posted_date, 
      expense.ex_trans_date, 
      expense.ex_description, 
      expense.ex_amount, 
      expense.ex_deduction, 
      expense.notes, 
      expense.ex_file_desc, 
      expense.insert_datetime, 
      expense.insert_user, 
      expense.insert_process, 
      expense.update_datetime, 
      expense.update_user, 
      expense.update_process 

    'For each item, make an expense object and add it to the ListView 
    For Each item In queryExceptions.ToList 
     Dim exp = New expense(item.ex_id, item.ex_type_id, item.override_ex_type_id, item.month_id, item.account_id, item.ex_posted_date, item.ex_trans_date, item.ex_description, item.ex_amount, 
            item.ex_deduction, item.notes, item.ex_file_desc, item.insert_datetime, item.insert_user, item.insert_process, item.update_datetime, item.update_user, item.update_process) 
     lvAllocation.Items.Add(exp) 
    Next 

    'Create list for expense dropdown 
    ExceptionTypeDropdown() 

End Sub 

运行从我的数据库获取的edmx数据模型。

我的问题是,如何使用表expense_type中存在的dat填充ComboBox列。这就像我在尝试一些我在网上找到的东西一样。任何帮助深表感谢。

Private Sub ExceptionTypeDropdown() 

    Dim expenseTypes = 
    From expense_type In dataEntities.expense_type 
    Select expense_type.ex_type_code, 
      expense_type.ex_type_desc 

    'Add the expense type combo box on the DataGrid 


End Sub 

Expense List Screenshot

请注意我的代码是C#比VB.Net多,但我想你可以翻译这一部分。

所以,你需要的是一个独立的项目源与所有可能的费用类型和所选值绑定到您的收藏:

在你的控制/窗口的XAML资源:

<CollectionViewSource x:Key="expenseTypesSource"/> 

在后面的初始化代码:

var expenseTypesSource = Resources["expenseTypesSource"] as CollectionViewSource; 
expenseTypesSource.Source = expenseTypes; // each item as { ex_type_code, ex_type_desc } 

组合框用法:

<ComboBox 
    ItemsSource="{Binding Source={StaticResource expenseTypesSource}}" 
    DisplayMemberPath="ex_type_desc" 
    SelectedValuePath="ex_type_code" 
    SelectedValue="{Binding ex_type_id}" 
    Width="120" /> 

正确使用DataContext后,您可以跳过部分代码,但我不打算在这里详细讨论。