private void BetterTreeView_ItemDrag(object sender, ItemDragEventArgs e)
{
// Get mouse position in client coordinates
Point p = PointToClient(MousePosition);
// Get drag node and select it
dragNode = (BetterTreeNode)e.Item;
SelectedNode = dragNode;
// Create the Graphics object from the node being dragged.
Bitmap bmp = new Bitmap(dragNode.Bounds.Width + Indent, dragNode.Bounds.Height);
Graphics gfx = Graphics.FromImage(bmp);
// Draw node icon into the bitmap
gfx.DrawImage(ImageList.Images[dragNode.ImageIndex], 0, 0);
// Draw node label into bitmap
gfx.DrawString(dragNode.Text, Font, new SolidBrush(ForeColor), 18f, 1f);
int dragImageWidth = dragNode.Bounds.Size.Width + Indent;
if (dragImageWidth > 256)
{
dragImageWidth = 256;
}
imageListDrag = Helpers.GenerateImageList(new Bitmap[] { bmp },
dragImageWidth, dragNode.Bounds.Height);
// Compute delta between mouse position and node bounds
int dx = p.X + Indent - dragNode.Bounds.Left - Location.X;
int dy = p.Y - dragNode.Bounds.Top - Location.Y;
// Begin dragging image
if (DragHelper.ImageList_BeginDrag(imageListDrag.Handle, 0, dx, dy))
{
// Begin dragging
DoDragDrop(bmp, DragDropEffects.Move);
// End dragging image
DragHelper.ImageList_EndDrag();
}
}
void TemplateTree_ItemDrag(object sender, ItemDragEventArgs e)
{
TreeNode Node = e.Item as TreeNode;
Boolean IsModule = Convert.ToBoolean(Node.Tag);
if (IsModule)
{
dragNode = e.Item as TreeNode;
TemplateTree.SelectedNode = dragNode;
int imageWidth = dragNode.Bounds.Size.Width + TemplateTree.Indent;
imageListDrag.Images.Clear();
imageListDrag.ImageSize = new Size(imageWidth > 255 ? 255 : imageWidth, dragNode.Bounds.Height);
Bitmap bmp = new Bitmap(dragNode.Bounds.Width + TemplateTree.Indent, dragNode.Bounds.Height);
Graphics gfx = Graphics.FromImage(bmp);
gfx.DrawImage(imageList1.Images[dragNode.ImageIndex], 0, 0);
gfx.DrawString(dragNode.Text, TemplateTree.Font,
new SolidBrush(TemplateTree.ForeColor),
(float)TemplateTree.Indent, 1.0f);
imageListDrag.Images.Add(bmp);
Point p = TemplateTree.PointToClient(Control.MousePosition);
int dx = p.X + TemplateTree.Indent - dragNode.Bounds.Left;
int dy = p.Y - dragNode.Bounds.Top;
if (DragHelper.ImageList_BeginDrag(imageListDrag.Handle, 0, dx, dy))
{
TemplateTree.DoDragDrop(bmp, DragDropEffects.Move);
DragHelper.ImageList_EndDrag();
}
}
else
{
return;
}
}
/// <summary>
/// Gets called when an item starts to be dragged.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void _ItemDrag(object sender, ItemDragEventArgs e)
{
var treeView = sender as TreeView;
if (treeView == null || treeView != this._treeView)
{
return;
}
// do not allow root nodes to be dragged
if (!this._canDragRootNodes && treeView.Nodes.Contains((TreeNode)e.Item))
{
return;
}
// Get drag node and select it
var treeNode = (TreeNode)e.Item;
this._draggedNode = treeNode;
treeView.SelectedNode = this._draggedNode;
// Reset image list used for drag image
var imageList = this._dragImageList;
imageList.Images.Clear();
var nodeImage = treeNode.GetImage();
imageList.ImageSize = new Drawing.Size(Math.Min(256, treeNode.Bounds.Size.Width + (nodeImage?.Width + 1 ?? 0)), Math.Min(256, treeNode.Bounds.Height));
// Create new bitmap
// This bitmap will contain the tree node image to be dragged
var bmp = new Bitmap(imageList.ImageSize.Width, imageList.ImageSize.Height);
// Get graphics from bitmap
var gfx = Graphics.FromImage(bmp);
// Draw node icon into the bitmap
if (nodeImage != null)
{
gfx.DrawImage(nodeImage, 0, 0);
}
// Draw node label into bitmap
gfx.DrawString(treeNode.Text, treeView.Font, new SolidBrush(treeView.ForeColor), nodeImage?.Width + 1 ?? 0, 1.0f);
// Add bitmap to imagelist
imageList.Images.Add(bmp);
// Compute hotspot
const int dx = 16;
const int dy = 16;
// Begin dragging image
if (!DragHelper.ImageList_BeginDrag(imageList.Handle, 0, -dx, -dy))
{
return;
}
treeView.DoDragDrop(treeNode, DragDropEffects.Move);
// End dragging image
DragHelper.ImageList_EndDrag();
}
