Question

I have an application that needs to display a grid of data consisting mostly of boolean values, and checkbox columns fit the bill. There will be about 40-60 checkbox columns with around 200 rows. I thought it would be trivial to do something like that in WPF.

I am unable to even get near a decent horizontal scrolling experience with WPF. To see what I’m talking about, create a Window and place a DataGrid on it, and set AutoGenerateColumns="True", then add the following in the constructor after InitializeComponent();:

dataGrid1.ItemsSource = Create(200, i => new { b1 = true, b2 = false, b3 = true, b4 = false, b5 = true, b6 = false, b7 = true, b8 = false, b9 = true,
                                               b10 = false, b11 = true, b12 = false, b13 = true, b14 = false, b15 = true, b16 = false, b17 = true, b18 = false, b19 = true, b20 = false, b21 = true,
                                               b22 = false, b23 = true, b24 = false, b25 = true, b26 = false, b27 = true, b28 = false, b29 = true, b30 = false, b31 = true, b32 = false });

It requires this method, add it too:

ObservableCollection<T> Create<T>(int count, Func<int, T> creator)
{
    return new ObservableCollection<T>(Enumerable.Range(0, count).Select(creator));
}

Run the application, and attempt to scroll horizontally. Horrible, isn’t it? Vertical scrolling isn’t too hot either.

I did the same with a WinForms application and scrolling was butter smooth in all directions, and looked as good as WPF after forcing the DataGridView‘s DoubleBuffered property to true. To compare, create a new Form, plop a DataGridView and add the following to the constructor after InitializeComponent();:

typeof(DataGridView).GetProperty("DoubleBuffered", BindingFlags.Instance | BindingFlags.NonPublic).SetValue(dataGridView1, true, null);
for (int i = 0; i < 64; i++)
    dataGridView1.Columns.Add(new DataGridViewCheckBoxColumn {HeaderText = "C" + i, Width = 30});
for (int i = 0; i < 400; i++)
    dataGridView1.Rows.Add();

This has twice the number of columns, twice the number of rows, and it scrolls as smooth as a newborn’s bottom, both horizontally and vertically.

But unfortunately I can’t do what I need with WinForms. I need templated columns. I need composability.

To solve the scrolling issue in WPF, I tried all combinations of the following:

• EnableColumnVirtualization (true/false)
• EnableRowVirtualization (true/false)
• ScrollViewer.CanContentScroll (true/false) – false improves vertical scrolling only
• Fixed-sized columns
• Fixed-sized data grid
• VirtualizingStackPanel.VirtualizationMode (Recycling/Standard) – _{Recycling has a bug where it will recycle a CheckBox control that is checked and place it in a new row where it should be unchecked, causing a fading out animation. This makes checkboxes appear to have a “ghosting” effect.}
• ScrollViewer.IsDeferredScrollingEnabled – I’m sorry but I can’t accept downgrading to Windows 3.1-style scrolling for something so trivial.

I’m willing to accept subpar performance. I don’t expect anything like the smoothness of WinForms (WPF is after all giving me so much more, although this should have been offset by WPF’s GPU acceleration). I just want something usable, even just barely usable.

Answer 1

As stated in my comment I am not sure of the question. If you are looking for performance of a grid in WPF then go ListView / GridView. Unless there are some feature of DataGrid you have to have. It is more code but worth it. I have a GridView with 40 columns and 1000 rows and good performance (and DataGrid performance was bad).