public CheckBoxComboBoxListControl(CheckBoxComboBox owner)
{
DoubleBuffered = true;
_CheckBoxComboBox = owner;
_Items = new CheckBoxComboBoxItemList(_CheckBoxComboBox);
BackColor = SystemColors.Window;
// AutoScaleMode = AutoScaleMode.Inherit;
AutoScroll = true;
ResizeRedraw = true;
// if you don't set this, a Resize operation causes an error in the base class.
MinimumSize = new Size(1, 1);
MaximumSize = new Size(500, 500);
}
/// <summary>
/// Maintains the controls displayed in the list by keeping them in sync with the actual
/// items in the combobox. (e.g. removing and adding as well as ordering)
/// </summary>
public void SynchroniseControlsWithComboBoxItems()
{
SuspendLayout();
if (_CheckBoxComboBox._MustAddHiddenItem)
{
_CheckBoxComboBox.Items.Insert(
0, _CheckBoxComboBox.GetCSVText(false)); // INVISIBLE ITEM
_CheckBoxComboBox.SelectedIndex = 0;
_CheckBoxComboBox._MustAddHiddenItem = false;
}
Controls.Clear();
#region Disposes all items that are no longer in the combo box list
for (int Index = _Items.Count - 1; Index >= 0; Index--)
{
CheckBoxComboBoxItem Item = _Items[Index];
if (!_CheckBoxComboBox.Items.Contains(Item.ComboBoxItem))
{
_Items.Remove(Item);
Item.Dispose();
}
}
#endregion
#region Recreate the list in the same order of the combo box items
bool HasHiddenItem =
_CheckBoxComboBox.DropDownStyle == ComboBoxStyle.DropDownList &&
_CheckBoxComboBox.DataSource == null &&
!DesignMode;
var NewList = new CheckBoxComboBoxItemList(_CheckBoxComboBox);
for (int Index0 = 0; Index0 <= _CheckBoxComboBox.Items.Count - 1; Index0++)
{
object Object = _CheckBoxComboBox.Items[Index0];
CheckBoxComboBoxItem Item = null;
// The hidden item could match any other item when only
// one other item was selected.
if (Index0 == 0 && HasHiddenItem && _Items.Count > 0)
{
Item = _Items[0];
}
else
{
int StartIndex = HasHiddenItem
? 1 // Skip the hidden item, it could match
: 0;
for (int Index1 = StartIndex; Index1 <= _Items.Count - 1; Index1++)
{
if (_Items[Index1].ComboBoxItem == Object)
{
Item = _Items[Index1];
break;
}
}
}
if (Item == null)
{
Item = new CheckBoxComboBoxItem(_CheckBoxComboBox, Object);
Item.Font = _CheckBoxComboBox.Font;
Item.ApplyProperties(_CheckBoxComboBox.CheckBoxProperties);
}
NewList.Add(Item);
Item.Dock = DockStyle.Top;
}
_Items.Clear();
_Items.AddRange(NewList);
#endregion
#region Add the items to the controls in reversed order to maintain correct docking order
if (NewList.Count > 0)
{
// This reverse helps to maintain correct docking order.
NewList.Reverse();
// If you get an error here that "Cannot convert to the desired
// type, it probably means the controls are not binding correctly.
// The Checked property is binded to the ValueMember property.
// It must be a bool for example.
Controls.AddRange(NewList.ToArray());
}
#endregion
// Keep the first item invisible
if (_CheckBoxComboBox.DropDownStyle == ComboBoxStyle.DropDownList &&
_CheckBoxComboBox.DataSource == null &&
!DesignMode)
{
_CheckBoxComboBox.CheckBoxItems[0].Visible = false;
}
ResumeLayout();
}