I have the following tables:
Company {CompanyID, CompanyName}
Deal {CompanyID, Value}And I have a listbox:
<ListBox Name="Deals"
Height="100" Width="420" Margin="0,20,0,0" HorizontalAlignment="Left" VerticalAlignment="Top"
Visibility="Visible" IsSynchronizedWithCurrentItem="True"
ItemsSource="{Binding}" SelectionChanged="Deals_SelectionChanged">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding companyRowByBuyFromCompanyFK.CompanyName}" FontWeight="Bold" />
<开发者_StackOverflow社区;TextBlock Text=" -> TGS -> " />
<TextBlock Text="{Binding BuyFrom}" FontWeight="Bold" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
As you can see, I want to display the CompanyName rather then the ID which is a foreign Key. The relation "companyRowByBuyFromCompanyFK" exists, as in Deals_SelectionChanged I can access companyRowByBuyFromCompanyFK property of the Deals row, and I also can access the CompanyName propert of that row.
Is the reason why this is not working because XAML binding uses the [] indexer? Rather than properties on the CompanyRows in my DataTable?
At the moment im getting values such as
- -> TGS -> 3
- -> TGS -> 4
Edit Binding Error Update
System.Windows.Data Error: 39 : BindingExpression path error: 'companyRowByBuyFromCompanyFK' property not found on 'object' ''DataRowView' (HashCode=30295189)'. BindingExpression:Path=companyRowByBuyFromCompanyFK.CompanyName; DataItem='DataRowView' (HashCode=30295189); target element is 'TextBlock' (Name=''); target property is 'Text' (type 'String')
Looks like its not converting the DataRowView item into a SuppliersRow
What would be the best way to accomplish this?
Make a converter to convert foreign keys using Table being referenced as custom parameter.
Create Table View for each table? This would be long winded as I have quite a large number of tables that have foreign keys.
Somebody kill me.... thanks for pointing out the output window I always forget about that! :(
I found the solution by looking at the output window which was the following
System.Windows.Data Error: 39 : BindingExpression path error: 'companyRowByBuyFromCompanyFK' property not found on 'object' ''DataRowView
I figured out that the DataTemplate binding was binding to the SelectedItem of the DataTemplate which is a DataRowView and not the actual strong typed data. Luckily the DataRowView class has a Row property pointing to the DataRow (which is the supplierRow) class therefore I could bind from there as normal. Fix was in the followign line.
<TextBlock Text="{Binding companyRowByBuyFromCompanyFK.CompanyName}" FontWeight="Bold" />
Changing this to the following worked as I expected it to.
<TextBlock Text="{Binding Row.companyRowByBuyFromCompanyFK.CompanyName}" FontWeight="Bold" />
How about setting a multibinding in the datatemplate that converts the row (the datasource from the listitem), together with a hierarchical binding (that passes the reference to the other table from the parent control) and the name of the field in the other table to search for the id within?
<UserControl x:Class="local:MyUserControl">
<ListBox ItemsSource="{Binding Items}">
<ListBox.ItemTemplate>
<DataTemplate>
<Label>
<Label.Content>
<MultiBinding Converter="{StaticResource myConverter}">
<Binding Path="OtherId" />
<Binding
RelativeSource="RelativeSource FindAncestor,
AncestorType={x:Type local:MyUserControl}}}"
Path="OtherTable" />
</MultiBinding>
</Label.Content>
</Label>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</UserControl>
In the converter:
public object Convert(object[] values, Type targetType, object parameter,
System.Globalization.CultureInfo culture)
{
// TODO: Input type checks
// TODO: Castings, find key in other table, return relevant field
return (values[1] as IDictionary<String, String>)[values[0] as String];
}
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