MVVM gridview binding to datatable WPF - wpf

Question

I am new to MVVM and databinding and I am having some trouble binding a gridview to a datatable dynamically. I am able to get the column headers to bind, but no data is being displayed in the grid itself.
My model simply returns a data table as the result of a SQL string passed to it.
My viewmodel just wraps the datatable and gets bound to the view.
Right now I am just trying to display the data by populating the gridview from the main window, but only the headers are being displayed.
I know there is data in the model.Results datatable though.
My viewmodel:
public class ResultsViewModel
{
private DataTable _dt;
public ResultsViewModel()
{
DataSource _ds = new DataSource();
_dt = _ds.Execute("select * from tbl_users");
}
public DataTable Results
{
get { return _dt; }
set { _dt = value; }
}
}
My code to populate the gridview from the mainwindow:
public MainWindow()
{
InitializeComponent();
ResultsView view = new ResultsView();
ResultsViewModel model = new ResultsViewModel();
GridView Grid = new GridView();
foreach (DataColumn col in model.Results.Columns)
{
Grid.Columns.Add(new GridViewColumn
{
Header = col.ColumnName,
DisplayMemberBinding = new Binding(col.ColumnName)
});
}
view._listView.View = Grid;
view.DataContext = model;
view.SetBinding(ListView.ItemsSourceProperty, new Binding());
_placeholder.Content = view;
}
The ResultsView xaml:
<UserControl x:Class="InDevReporting.Views.ResultsView"
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"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<ListView x:Name="_listView" />
</Grid>

Answer 1

Try setting your data context to model.Results.
ie change this line:
view.DataContext = model;
to this:
view.DataContext = model.Results;
Generally you would create a dependency property on your view model and specify the binding in the XAML. The grid should be clever enough to figure out what columns to draw:
<ListView ItemsSource="{Binding Results}" />
public MainWindow()
{
InitializeComponent();
// your code to instance and populate model
this.DataContext = model;
}
public class ResultsViewModel : DependencyObject
{
public static readonly DependencyProperty ResultsProperty = DependencyProperty.Register("Results", typeof(DataTable) , typeof(ResultsViewModel));
public DataTable Results
{
get { (DataTable)GetValue(ResultsProperty); }
set { SetValue(ResultsProperty, value); }
}
}
I've tapped this out from memory, so apologies if the code isn't exactly right. The easiest way to declare a new dependency property is to use the propdp code snippet. It's a lot of syntax to memorize.