How to have custom control in DataGridView display object's value?

[Cryo75]

I have a sample project located here

The project has a main form `Form1` where the user can enter customers in a datagridview. The `CustomerType` column is a custom control and when the user clicks the button, a search form `Form2` pops up.

The search form is populated with a list of type `CustomerType`. The user can select a record by double-clicking on the row, and this object should be set in the custom control. The `DataGridView` should then display the `Description` property but in the background each cell should hold the value (ie. the `CustomerType` instance).

The relevant code is located in the following classes:

The column class:


public class DataGridViewCustomerTypeColumn : DataGridViewColumn
{
public DataGridViewCustomerTypeColumn()
: base(new CustomerTypeCell())
{ }

public override DataGridViewCell CellTemplate
{
get { return base.CellTemplate; }
set
{
if (value != null && !value.GetType().IsAssignableFrom(typeof(CustomerTypeCell)))
{
throw new InvalidCastException("Should be CustomerTypeCell.");
}

base.CellTemplate = value;
}
}
}

The cell class:


public class CustomerTypeCell : DataGridViewTextBoxCell
{
public CustomerTypeCell()
: base()
{ }

public override void InitializeEditingControl(int rowIndex, object initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
{
base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);

CustomerTypeSearch ctl = DataGridView.EditingControl as CustomerTypeSearch;

if (this.Value == null)
ctl.Value = (CustomerType)this.DefaultNewRowValue;
else
ctl.Value = (CustomerType)this.Value;
}

public override Type EditType
{
get { return typeof(CustomerTypeSearch); }
}

public override Type ValueType
{
get { return typeof(CustomerType); }
}

public override object DefaultNewRowValue
{
get { return null; }
}
}

And the custom control:


public partial class CustomerTypeSearch : UserControl, IDataGridViewEditingControl
{
private DataGridView dataGridView;
private int rowIndex;
private bool valueChanged = false;
private CustomerType value;

public CustomerTypeSearch()
{
InitializeComponent();
}

public CustomerType Value
{
get { return this.value; }
set
{
this.value = value;

if (value != null)
textBoxSearch.Text = value.Description;
else
textBoxSearch.Clear();
}
}

private void buttonSearch_Click(object sender, EventArgs e)
{
Form2 f = new Form2();

DialogResult dr = f.ShowDialog(this);

if (dr == DialogResult.OK)
{
Value = f.SelectedValue;
}
}

#region IDataGridViewEditingControl implementation

public object EditingControlFormattedValue
{
get
{
if (this.value != null)
return this.value.Description;
else
return null;
}
set
{
if (this.value != null)
this.value.Description = (string)value;
}
}

public object GetEditingControlFormattedValue(DataGridViewDataErrorContexts context)
{
return EditingControlFormattedValue;
}

public void ApplyCellStyleToEditingControl(DataGridViewCellStyle dataGridViewCellStyle)
{
this.BorderStyle = BorderStyle.None;
this.Font = dataGridViewCellStyle.Font;
}

public int EditingControlRowIndex
{
get { return rowIndex; }
set { rowIndex = value; }
}

public bool EditingControlWantsInputKey(Keys key, bool dataGridViewWantsInputKey)
{
return false;
}

public void PrepareEditingControlForEdit(bool selectAll)
{
//No preparation needs to be done
}

public bool RepositionEditingControlOnValueChange
{
get { return false; }
}

public DataGridView EditingControlDataGridView
{
get { return dataGridView; }
set { dataGridView = value; }
}

public bool EditingControlValueChanged
{
get { return valueChanged; }
set { valueChanged = value; }
}

public Cursor EditingPanelCursor
{
get { return base.Cursor; }
}

#endregion

private void CustomerTypeSearch_Resize(object sender, EventArgs e)
{
buttonSearch.Left = this.Width - buttonSearch.Width;
textBoxSearch.Width = buttonSearch.Left;
}
}

However, the `DataGridView` is not displaying the text and it also is not keeping the `CustomerType` value for each cell.

What am I missing?

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