Hello Marianne,

thank you for the sample.

There seems to be one misunderstanding. After the user has selected rows, columns or specific cells he should be able to toggle the check/uncheck state of all CheckBoxes, within his selection, by pressing just one key - preferably the space key.

I modified my sample application again. Please take a look at the attached project (file WPF_xamGrid_toggleCheckBoxes.zip).

When using the Add key everything works great now and I can toggle the check/uncheck state of all CheckBoxes within the actual selection. This is a familiar behavior for users working with CheckBoxes in a grid. This works for selected rows, columns or specific cells.

The only problem we still have is the fact that all SelectionSettings get lost when you press the Space key!

I implemented a handler "grid_PreviewKeyDown" for the PreviewKeyDown event. After selecting e.g. one column you get the Trace output:
  grid_PreviewKeyDown e.Key: Space
    grid.SelectionSettings.SelectedCells.Count: 0
    grid.SelectionSettings.SelectedRows.Count: 0
    grid.SelectionSettings.SelectedColumns.Count: 1

In the handler "XamGrid_KeyDown" you then get the following output:
  XamGrid_KeyDown e.Key: Space
    grid.SelectionSettings.SelectedCells.Count: 1
    grid.SelectionSettings.SelectedRows.Count: 0
    grid.SelectionSettings.SelectedColumns.Count: 0

Questions:
1. Is ist possible to prevent the actual XamGrid behavior after pressing the Space key?
2. Is it possible to "cancel" the PreviewKeyDown event, if the Space key was pressed?
3. If the previous questions must be answered with "No" could you make a suggestion how we could solve this problem?
   Do we really have to save the SelectionSetting information in grid_PreviewKeyDown separately for using it afterwards in XamGrid_KeyDown?

Regards,
chrisobs

Hi,

I'm attaching my updated version of your sample.

I had apparently left out the selectedcells in my code, which I have added now.  The other thing I noticed was that using the Space key with the LeftCtrl key was problematic for  selecting cells.  So I modified the sample to use the key pad Add button in conjunction with the LeftCtrl key.

You can select cells, rows and columns, using the Shift or Ctrl key in combination with the left mouse button.  In order to toggle the checkboxes in the selected cells, rows, and columns, use the combination of Ctrl key plus the Add button to make the checkboxes checked or the Add button alone to make the selected checkboxes unchecked. 

Please let me know if you have any questions.

Hello Marianne,

thank you for your reply.
I transferred your XamGrid_KeyDown-Code to the test-application, I sent you before, but I still have the problem with the Selection information getting lost. So it is not possible to toggle any checkboxes of former selected cells!

If I select a column and the press the space key I still get the following trace output:
HeaderControl_PreviewMouseDown:
grid.SelectionSettings.SelectedColumns.Count: 1
XamGrid_KeyDown:
grid.SelectionSettings.SelectedCells.Count: 1
grid.SelectionSettings.SelectedRows.Count: 0
grid.SelectionSettings.SelectedColumns.Count: 0

So the main problem remains. At the moment you press the space key, the selections information is lost and only one cell remains selected - probably the former ActiveCell!? How can I solve this problem?

Regards,

chrisobs

Hi, 

Please excuse the delay in responding.

Your code in the KeyDown event needs to identify whether there are any SelectedCells, SelectedRows and SelectedColumns and then update the underlying data which will be reflected in the checkbox. 

I ended up having to also use an additional key to determine if the value should be set to true or false. 

I think the following code will achieve what you want.  

private void XamGrid_KeyDown(object sender, KeyEventArgs e)

{

     DataView dv = grid.ItemsSource as DataView;

     DataTable d = dv.Table as DataTable;

     if (e.Key == Key.Space)

     {

          System.Diagnostics.Trace.WriteLine("XamGrid_KeyDown:");

          System.Diagnostics.Trace.WriteLine("  grid.SelectionSettings.SelectedCells.Count: " + grid.SelectionSettings.SelectedCells.Count.ToString());

          System.Diagnostics.Trace.WriteLine("  grid.SelectionSettings.SelectedRows.Count: " + grid.SelectionSettings.SelectedRows.Count.ToString());

          System.Diagnostics.Trace.WriteLine("  grid.SelectionSettings.SelectedColumns.Count: " + grid.SelectionSettings.SelectedColumns.Count.ToString());

 //Requirement for our Application: Toggle Check/Uncheck state of all CheckBoxes in the secected columns or rows

           for (int r = 0; r < grid.SelectionSettings.SelectedRows.Count; r++)

           {

                int ri = grid.SelectionSettings.SelectedRows[r].Index;

                for (int c = 0; c < d.Rows[ri].ItemArray.AsEnumerable().Count(); c++)

                {

                   if  (!Keyboard.IsKeyDown(Key.LeftCtrl))

                   {

                       d.Rows[ri].SetField<bool>(c, false);

                   }

                   else

                   {

                       d.Rows[ri].SetField<bool>(c, true);

                   }

                }

            }

            for (int c = 0; c < grid.SelectionSettings.SelectedColumns.Count; c++)

            {

                string ckey = grid.SelectionSettings.SelectedColumns[c].Key;

                for (int r = 0; r < d.Rows.Count; r++)

                {

                   if  (!Keyboard.IsKeyDown(Key.LeftCtrl))

                   {

                       d.Rows[r].SetField<bool>(ckey, false);

                   }

                   else

                   {

                       d.Rows[r].SetField<bool>(ckey, true);

                   }

               }

            }              

       }

  }

Please let me know if you have any questions.