private void ListDragTarget_DragOver(object sender, DragEventArgs e)
{
// Determine whether string data exists in the drop data. If not, then
// the drop effect reflects that the drop cannot occur.
if (!e.Data.GetDataPresent(typeof(System.String)))
{
e.Effect = DragDropEffects.None;
DropLocationLabel.Text = "None - no string data.";
return;
}
// Set the effect based upon the KeyState.
if ((e.KeyState & (8 + 32)) == (8 + 32) &&
(e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link)
{
// KeyState 8 + 32 = CTL + ALT
// Link drag-and-drop effect.
e.Effect = DragDropEffects.Link;
}
else if ((e.KeyState & 32) == 32 &&
(e.AllowedEffect & DragDropEffects.Link) == DragDropEffects.Link)
{
// ALT KeyState for link.
e.Effect = DragDropEffects.Link;
}
else if ((e.KeyState & 4) == 4 &&
(e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move)
{
// SHIFT KeyState for move.
e.Effect = DragDropEffects.Move;
}
else if ((e.KeyState & 8) == 8 &&
(e.AllowedEffect & DragDropEffects.Copy) == DragDropEffects.Copy)
{
// CTL KeyState for copy.
e.Effect = DragDropEffects.Copy;
}
else if ((e.AllowedEffect & DragDropEffects.Move) == DragDropEffects.Move)
{
// By default, the drop action should be move, if allowed.
e.Effect = DragDropEffects.Move;
}
else
{
e.Effect = DragDropEffects.None;
}
// Get the index of the item the mouse is below.
// The mouse locations are relative to the screen, so they must be
// converted to client coordinates.
indexOfItemUnderMouseToDrop =
ListDragTarget.IndexFromPoint(ListDragTarget.PointToClient(new Point(e.X, e.Y)));
// Updates the label text.
if (indexOfItemUnderMouseToDrop != ListBox.NoMatches)
{
DropLocationLabel.Text = "Drops before item #" + (indexOfItemUnderMouseToDrop + 1);
}
else
{
DropLocationLabel.Text = "Drops at the end.";
}
}
private void DeleteBox_DragDrop(object sender, DragEventArgs e)
{
IndexOfItemUnderMouseToDrop = ListBox.NoMatches;
AlignTaskEnable();
AlignHelpMessage();
ListDragTarget.Invalidate();
}
private void ListDragTarget_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)
{
// Ensure that the list item index is contained in the data.
if (TaskListBox.IsValidDragData(e.Data))
{
// Perform drag-and-drop, depending upon the effect.
if (e.Effect == DragDropEffects.Copy ||
e.Effect == DragDropEffects.Move)
{
AbstractProcessingTask task = null;
if (TaskListBox.DragDataSource(e.Data) == ListDragTarget)
{
task = (AbstractProcessingTask)(TaskListBox.DragDataTask(e.Data));
}
else // if we are comming from source list => Create a new instance
if (task == null)
{
task = TaskListBox.DragDataTask(e.Data).Clone();
}
if (ListDragTarget.IsValidInsertionIndex(IndexOfItemUnderMouseToDrop, task, In)) // if place is ok
{
((TaskListBox)sender).Insert(IndexOfItemUnderMouseToDrop, task);
}
else if (TaskListBox.DragDataSource(e.Data) == ListDragTarget) // if place is not ok, but we came from the destination listbox, we reinsert the task when she come from
{
((TaskListBox)sender).Insert(TaskListBox.DragDataIndex(e.Data), task);
}
ListDragTarget.Invalidate();
IndexOfItemUnderMouseToDrop = ListBox.NoMatches;
}
}
AlignTaskEnable();
AlignHelpMessage();
}
private void ListDragTarget_DragOver(object sender, System.Windows.Forms.DragEventArgs e)
{
// Determine whether string data exists in the drop data. If not, then
// the drop effect reflects that the drop cannot occur.
bool valid = TaskListBox.IsValidDragData(e.Data);
if (!valid)
{
e.Effect = DragDropEffects.None;
return;
}
int lastIndex = IndexOfItemUnderMouseToDrop;
IndexOfItemUnderMouseToDrop = ListDragTarget.IndexFromPoint(ListDragTarget.PointToClient(new Point(e.X, e.Y)));
if (sender == ListDragTarget)
{
if (IndexOfItemUnderMouseToDrop == -1)
{
IndexOfItemUnderMouseToDrop = ListDragTarget.Count;
}
ListDragTarget.Invalidate(lastIndex);
ListDragTarget.Invalidate(IndexOfItemUnderMouseToDrop);
if (ListDragTarget.IsValidInsertionIndex(IndexOfItemUnderMouseToDrop, TaskListBox.DragDataTask(e.Data), In))
{
e.Effect = DragDropEffects.Copy;
return;
}
else
{
IndexOfItemUnderMouseToDrop = -1;
e.Effect = DragDropEffects.Move;
return;
}
}
e.Effect = DragDropEffects.Move;
}
private void ListDragSource_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
{
if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
{
if (!ListDragTarget.Lock)
{
bool draggable = true;
if (sender == ListDragTarget)
{
draggable = ListDragTarget.RemovableForTaskFlow(IndexOfItemUnderMouseToDrag);
}
if (!draggable)
{
Cursor.Current = Cursors.No;
}
// If the mouse moves outside the rectangle, start the drag.
if (draggable && dragBoxFromMouseDown != Rectangle.Empty &&
!dragBoxFromMouseDown.Contains(e.X, e.Y))
{
// Create custom cursors for the drag-and-drop operation.
try
{
TaskListBox ctrl = (TaskListBox)sender;
MyNormalCursor = ctrl.CreateCursor(IndexOfItemUnderMouseToDrag, true);
MyNodropCursor = ctrl.CreateCursor(IndexOfItemUnderMouseToDrag, false);
}
catch
{
}
finally
{
// The screenOffset is used to account for any desktop bands
// that may be at the top or left side of the screen when
// determining when to cancel the drag drop operation.
screenOffset = SystemInformation.WorkingArea.Location;
object data = ((TaskListBox)sender).GetDragData(IndexOfItemUnderMouseToDrag);
if (sender == ListDragTarget)
{
((TaskListBox)sender).RemoveAt(IndexOfItemUnderMouseToDrag);
AlignHelpMessage();
}
// Proceed with the drag-and-drop, passing in the list item.
DragDropEffects dropEffect = ((TaskListBox)sender).DoDragDrop(data, DragDropEffects.All | DragDropEffects.Copy);
// Dispose of the cursors since they are no longer needed.
if (MyNormalCursor != null)
{
MyNormalCursor.Dispose();
}
if (MyNodropCursor != null)
{
MyNodropCursor.Dispose();
}
}
}
}
}
else
{
if (sender is TaskListBox)
{
TaskListBox listbox = (TaskListBox)sender;
int newHoveredIndex = listbox.IndexFromPoint(e.Location);
if (newHoveredIndex == -1)
{
this.ToolTip.ShowAlways = false;
}
if (hoveredIndex != newHoveredIndex)
{
hoveredIndex = newHoveredIndex;
if (hoveredIndex > -1)
{
AbstractProcessingTask task = listbox.Get(hoveredIndex);
if (task != null)
{
this.ToolTip.Active = false;
this.ToolTip.SetToolTip(listbox, task.ToolTip);
this.ToolTip.Active = true;
this.ToolTip.ShowAlways = true;
}
}
}
}
}
}
