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 DeleteBox_DragDrop(object sender, DragEventArgs e)
{
IndexOfItemUnderMouseToDrop = ListBox.NoMatches;
AlignTaskEnable();
AlignHelpMessage();
ListDragTarget.Invalidate();
}
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;
}