I've created a C# windows form dataGridview with two DataGridViewTextBoxColumns, column1 simply displays a static string and column2 houses different controls types e.g. (DataGridViewTextBoxCell, DataGridViewCheckBoxCell, DataGridViewButtonCell, etc). I'm trying to create/implement and custom comboBoxCell that allows the user to add new items and remove existing items from my custom comboBoxCell...The problems I'm having are: (1) If I have more than one custom comboBox in my column they all are sharing the same dataGridViewEditingControl so I'm unable to have different custom comboBoxes with different items/data. (2) When I leave anyone of the custom comboBoxes and enter another cell of a different type and return to anyone of my custom comboBoxes all the items/data are gone!
Here's an example of what I have.
<pre>
public class CustDataGridViewComboBoxCell : DataGridViewTextBoxCell
{
public string Name;
public DataGridView grid;
public CustDataGridViewComboBoxCell()
: base()
{
this.Value = "";
}
public override void InitializeEditingControl(int rowIndex, object initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
{
base.InitializeEditingControl(rowIndex, initialFormattedValue, dataGridViewCellStyle);
ComboBoxEdit cboEdit = this.DataGridView.EditingControl as ComboBoxEdit;
}
public override Type EditType
{
get { return typeof(ComboBoxEdit); }
}
public override Type ValueType
{
get { return typeof(String); }
}
public override object DefaultNewRowValue
{
get { return string.Empty; }
}
public override object Clone()
{
CustDataGridViewComboBoxCell dgvCell = base.Clone() as CustDataGridViewComboBoxCell;
if (dgvCell != null)
{
dgvCell.Name = this.Name;
}
return dgvCell;
}
}
public delegate void DropDownItemListEventHandler(object sender, List<string> items);
public class CustComboBox : ComboBox, IDataGridViewEditingControl
{
DataGridView grid;
private bool valueChanged = false;
int rowIndex;
List<string> items;
public event DropDownItemListEventHandler DropDownListHndlr;
public ComboBoxEdit()
:base()
{
this.Text = "";
this.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawFixed;
this.DropDownStyle = ComboBoxStyle.DropDown;
items = new List<string>();
}
public void Insert(string item)
{
if (item != null && item.Length > 0 && !this.Items.Contains(item))
{
this.Items.Insert(0, item);
this.Text = "";
items.Add(item);
if (DropDownListHndlr != null)
DropDownListHndlr(this, items);
}
}
public void Add(string item)
{
if (item != null && item.Length > 0 && !this.Items.Contains(item))
{
this.Items.Add(item);
this.Text = "";
items.Add(item);
if (DropDownListHndlr != null)
DropDownListHndlr(this, items);
}
}
public void Clear()
{
this.Items.Clear();
items.Clear();
}
protected override void OnSelectedValueChanged(EventArgs e)
{
string item = (string)this.Items[this.SelectedIndex];
this.Items.RemoveAt(this.SelectedIndex);
items.Remove(item);
this.Text = "";
if (DropDownListHndlr != null )
DropDownListHndlr(this, items);
}
protected override void OnDrawItem(DrawItemEventArgs e)
{
if (e.Index < 0)
return;
string txt = (string)base.Items[e.Index];
e.DrawBackground();
Icon icon = Properties.Resources.delete;
e.Graphics.DrawImage(icon.ToBitmap(), e.Bounds.X, e.Bounds.Y, 15, 15);
e.Graphics.DrawString(txt, base.Font, System.Drawing.Brushes.Black, new RectangleF(e.Bounds.X + 15, e.Bounds.Y, e.Bounds.Width, e.Bounds.Height));
e.DrawFocusRectangle();
}
// Implementation of IDataGridViewEditingControl Interface
public DataGridView EditingControlDataGridView
{
get { return grid; }
set { grid = value; }
}
public object EditingControlFormattedValue
{
get { return this.Text; }
set { this.Text = (string)value; }
}
public int EditingControlRowIndex
{
get { return rowIndex; }
set { rowIndex = value; }
}
public bool EditingControlValueChanged
{
get { return valueChanged; }
set { valueChanged = value; }
}
public Cursor EditingPanelCursor
{
get { return base.Cursor; }
}
public bool RepositionEditingControlOnValueChange
{
get { return false; }
}
public void ApplyCellStyleToEditingControl(DataGridViewCellStyle dataGridViewCellStyle)
{
}
public bool EditingControlWantsInputKey(Keys key, bool dataGridViewWantsInputKey)
{
return false;
}
public object GetEditingControlFormattedValue(DataGridViewDataErrorContexts context)
{
return EditingControlFormattedValue;
}
public void PrepareEditingControlForEdit(bool selectAll)
{
}
}
class Form1 : Form
{
DataGridView grid;
public Form1()
{
Initialize();
grid = new DataGridView();
grid.EditingControlShowing += new DataGridViewEditingControlShowingEventHandler(grid_EditingControlShowing);
grid.CellClick += new DataGridViewCellEventHandler(grid_CellClick);
grid.Columns.Add("colCtrlType","CtrlType");
grid.Columns.Add("colCtrl","Ctrl");
DataGridViewTextBoxCell cellTxt = new DataGridViewTextBoxCell();
cellTxt.Value = "custCombo";
CustDataGridViewComboBoxCell cellCustCombo = new CustDataGridViewComoBoxCell();
DataGridViewRow row = new DataGridViewRow();
row.Cells.Addnew DataGridViewCell[]{cellName, cellCustCombo});
grid.Rows.AddRange(row);
DataGridViewTextBoxCell cellTxt = new DataGridViewTextBoxCell();
cellTxt.Value = "TextBox1";
DataGridViewTextBoxCell cellTxt = new DataGridViewTextBoxCell();
DataGridViewRow row = new DataGridViewRow();
row.Cells.Addnew DataGridViewCell[]{cellName, cellTxt});
grid.Rows.AddRange(row);
DataGridViewTextBoxCell cellTxt = new DataGridViewTextBoxCell();
cellTxt.Value = "custCombo2";
CustDataGridViewComboBoxCell cellCustCombo2 = new CustDataGridViewComoBoxCell();
DataGridViewRow row = new DataGridViewRow();
row.Cells.Addnew DataGridViewCell[]{cellName, cellCustCombo2});
grid.Rows.Add(row);
grid.CellEndEdit += grid_CellEndEdit;
grid.EditingControlShowing += new DataGridViewEditingControlShowingEventHandler(grid_EditingControlShowing);
grid.CellClick += new DataGridViewCellEventHandler(grid_CellClick);
}
private void grid_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e){
if (e.Control.GetType() == typeof(ComboBoxEdit))
{
cboEdit = e.Control as ComboBoxEdit;
cboEdit.Validated -= new EventHandler(cboEdit_Validated);
cboEdit.DropDownListHndlr -= new DropDownItemListEventHandler(cboEdit_DropDownListHndlr);
cboEdit.Validated += new EventHandler(cboEdit_Validated);
cboEdit.DropDownListHndlr += new DropDownItemListEventHandler(cboEdit_DropDownListHndlr);
}
} private void cboEdit_Validated(object sender, EventArgs e)
{
cboEdit = grid.EditingControl as ComboBoxEdit;
cboEdit.Add(cboEdit.Text);
}
private void cboEdit_DropDownListHndlr(object sender, List<string> items)
{
// perform some operation with the items...
}
}
</pre>
So basically what's happening is if the user enters data into one the comboBoxes then clicks on another comboBox cell
it also is showing the items from the other comboBox when it should be empty. Also if the user click on the textBoxCell then both comboBoxes lose their items list and go blank.
I'm not sure what I'm doing here but can someone please help me out here?
Thanks in advance,
-DA
dee allen