@Koldo, you can just make all rows non editable for a while you need it using Editable method. I know it's not comfortable and pretty but should work. I'll try to add ReadOnly method that do this.
Hello uno
I have this now:
if (!readOnly)
gridPlantas.Accept();
else
gridPlantas.Reject();
I have tried this, but the results are the same:
for (int row = 0; row < grid.GetRowCount(); ++row)
for (int col = 0; col < grid.GetColumnCount(); ++col)
grid.GetItem(row, col).Editable(!readOnly);