Question

I have a DataGridView with a DataGridViewComboBoxColumn in the first column that is bind whith a List<MyClass> and a DisplayMember="name" (I dont set the valeumember because i want to get myclass when I accesse to value). The second column is a DataGridViewComboBoxColumn too. It will be bound to some List<String> based on the first DataGridViewComboBoxColumn selectedValue.

All this work just fine, the problem starts when I change the first DataGridViewComboBoxColumn.DataSource. When I add a new Myclass to the datasource it works, but if I select the class I will get an error:

System.ArgumentException: DataGridViewComboBoxCell value is not valid

Code:

//Set columns to Datagridview  
DataGridViewImageColumn btnEdit = new DataGridViewImageColumn();  
Image gear = (System.Drawing.Image)Properties.Resources.gear;  
btnEdit.Image = gear;  
datagridview.Columns.Add(btnEdit);  

//Table  
DataGridViewComboBoxColumn cbTable = new DataGridViewComboBoxColumn();  
cbTable.HeaderText = "Table";  
cbTable.Name = "Table";  
cbTable.DisplayMember = "NameToShow";  
//tableDataSource = cbTable.DataSource;  
//cbTable.DataSource = moduleClone.SqlQuery.Tables;  
datagridview.Columns.Add(cbTable);  

//...  
//...  
//...  

//Load data  
((DataGridViewComboBoxColumn)datagridview.Columns[1]).DataSource = (List<Table>)moduleClone.SqlQuery.Tables;  
//Work just fine  

//...  
//...  
//...  

//Now if i reload de data  
datagridview.Rows.Clear();  
((DataGridViewComboBoxColumn)datagridview.Columns[1]).DataSource = (List<Table>)moduleClone.SqlQuery.Tables;  
//This give me one message box with the exception several times when drawing the gridview.

Answer 1

Ok, I found a solution that works for me.
Instead use DataGridViewComboBoxColumn.DataSource, I directly change DataGridViewComboBoxColumn.Items. Has a probleme because you cant change DataGridViewComboBoxColumn.Items if DataGridViewComboBoxColumn.DataSource is set. So I define DataGridViewComboBoxColumn.DataSource = null before edit DataGridViewComboBoxColumn.Itens.

Code:

//Set columns to Datagridview  
DataGridViewImageColumn btnEdit = new DataGridViewImageColumn();  
Image gear = (System.Drawing.Image)Properties.Resources.gear;  
btnEdit.Image = gear;  
datagridview.Columns.Add(btnEdit);  

//Table  
DataGridViewComboBoxColumn cbTable = new DataGridViewComboBoxColumn();  
cbTable.HeaderText = "Table";  
cbTable.Name = "Table";  
cbTable.DisplayMember = "NameToShow";  
datagridview.Columns.Add(cbTable);  

//...  
//...  
//...  

//Load data  
((DataGridViewComboBoxColumn)datagridview.Columns[1]).Itens = (List<Table>)moduleClone.SqlQuery.Tables;  
//Work just fine  

//...  
//...  
//...  

//Now I reload de data  
datagridview.Rows.Clear();
((DataGridViewComboBoxColumn)datagridview.Columns[1]).DataSource = null; 
((DataGridViewComboBoxColumn)datagridview.Columns[1]).Items.clear();
((DataGridViewComboBoxColumn)datagridview.Columns[1]).Items= (List<Table>)moduleClone.SqlQuery.Tables;