public CarbolistItem AddItem(string title, object data = null)
{
if (title == null)
{
throw new Exception("Argument title must be non-null.");
}
Color backgroundColor = Items.Count % 2 == 0
? SampleButtonColors.BlueDark
: SampleButtonColors.BlueLight;
CarbolistItem item = new CarbolistItem(
title,
backgroundColor,
SampleButtonColors.BlueSelected,
itemSize,
new Point(0, Items.Count * itemSize.Height),
itemFont,
data,
this);
Controls.Add(item);
item.Background.Click += OnCarbolistItemClick;
item.Background.MouseDown += OnCarbolistItemMouseDown;
Items.Add(item);
Height += item.Height;
IsDragged = false;
return(item);
}
protected void OnCarbolistItemClick(object target, EventArgs e)
{
CarbolistItem item = ((Button)target).Parent as CarbolistItem;
if (item == SelectedItem)
{
if (CanDeselect)
{
item.Selected = false;
SelectedItem = null;
}
}
else
{
if (SelectedItem != null)
{
SelectedItem.Selected = false;
}
item.Selected = true;
SelectedItem = item;
}
// callback event listener
OnSelect?.Invoke(item);
}
public void RemoveItem(CarbolistItem item)
{
if (item == null)
{
throw new Exception("Argument item must be non-null");
}
if (item == SelectedItem)
{
SelectedItem = null;
}
Controls.Remove(item);
Items.Remove(item);
item.Background.Click -= OnCarbolistItemClick;
item.Background.MouseDown -= OnCarbolistItemMouseDown;
item.Dispose();
Height -= itemSize.Height;
IsDragged = false;
SortItems();
if (!CanDeselect)
{
SelectItem(Items[Items.Count - 1]);
}
}
public CarbolistItem SelectItem(CarbolistItem item)
{
if (!Items.Contains(item))
{
throw new Exception("Item not found in this Carbolist.");
}
OnCarbolistItemClick(item.Background, null);
return(item);
}
protected void OnDraggingItemMouseUp(object target, MouseEventArgs e)
{
Button button = target as Button;
button.MouseMove -= OnDraggingItemMouseMove;
button.MouseUp -= OnDraggingItemMouseUp;
// restore click event
if (isDraggingItem)
{
button.Click += OnCarbolistItemClick;
}
draggingItem = null;
isDraggingItem = false;
SortItems();
if (!IsDragged)
{
IsDragged = true;
}
}
protected void OnCarbolistItemMouseDown(object target, MouseEventArgs e)
{
// drag-and-drop preparations
// drag-and-drop only when the list has more than 1 item.
if (Items.Count <= 1)
{
return;
}
if (e.Button != MouseButtons.Left)
{
return;
}
Button button = target as Button;
draggingItem = button.Parent as CarbolistItem;
draggingStartPoint = e.Location;
button.MouseMove += OnDraggingItemMouseMove;
button.MouseUp += OnDraggingItemMouseUp;
}
