MVVM: how to set the datacontext of a user control
- by EVA
Hi,
I'm writing an application in WPF, using the MVVm toolkit and have problems with hooking up the viewmodel and view.
The model is created with ado.net entity framework.
The viewmodel:
public class CustomerViewModel
{
private Models.Customer customer;
//constructor
private ObservableCollection<Models.Customer> _customer = new ObservableCollection<Models.Customer>();
public ObservableCollection<Models.Customer> AllCustomers
{
get { return _customer; }
}
private Models.Customer _selectedItem;
public Models.Customer SelectedItem
{
get { return _selectedItem; }
}
public void LoadCustomers()
{
List<Models.Customer> list = DataAccessLayer.getcustomers();
foreach (Models.Customer customer in list)
{
this._customer.Add(customer);
}
}
}
And the view (no code behind at the moment):
<UserControl x:Class="Customers.Customer"
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"
mc:Ignorable="d"
xmlns:vm ="clr-namespace:Customers.ViewModels"
d:DesignHeight="300" d:DesignWidth="300"
xmlns:toolkit="http://schemas.microsoft.com/wpf/2008/toolkit" >
<Grid>
<toolkit:DataGrid ItemsSource="{Binding AllCustomers}" SelectedItem="{Binding SelectedItem, Mode=TwoWay}" AutoGenerateColumns="True">
</toolkit:DataGrid>
<toolkit:DataGrid ItemsSource="{Binding SelectedItem.Orders}">
</toolkit:DataGrid>
</Grid>
</UserControl>
And dataaccesslayer class:
class DataAccessLayer
{
public List<Customer> customers = new List<Customer>();
public static List<Customer> getcustomers()
{
entities db = new entities();
var customers = from c in db.Customer.Include("Orders")
select c;
return customers.ToList();
}
}
The problem is that no data is displayed simply because the data context is not set. I tried to do it in a code-behind but is did not work. I would prefer to do it in a xaml file anyway. Another problem is with the SelectedItem binding - the code is never used.
Thanks for help!
Regards,
EV.