Change Treeview Link line style

[gyanendar]

Hi All,
Can it be possible to change the Treeview link line(line connecting parent & Child node) style.Default its coming as dotted line .I want to make it solid line.
I am using WIN-FORM.
Please suggest.

-Gyanendar

[Plater]

I think you would have to change the draw mode to owner draw and draw the lines yourself?

[gyanendar]

If i draw line by myself ,how i'll find the exact path along which line would be drawn? We can hide the treeview link and need to get the exact co-ordinate of the point of Parent & Child

[Plater]

Well getting one is easy with the DrawNode event.
Hmm I think I have an idea on how to draw the lines, i'll get back to you

[gyanendar]

@Plater
Hi Plater,
Thanks for reply.
Here If we have the co-ordinate of points ,line can be drawn by e.Graphics.Drawline().

Gyanendar

[Plater]

Yeah I did the whole thing(sort of). I don't generally do the project, but this one caught my interest.

I do a few silly things to highlight what is going on, but it could certainly be adapted as needed.

 
private void treeView1_DrawNode(object sender, DrawTreeNodeEventArgs e)
{
  bool isOSDrawn = e.DrawDefault;
  Graphics g = e.Graphics;
  TreeNode tn = e.Node;
  Font DrawFont = treeView1.Font;
  Brush ForeBrush = new SolidBrush(treeView1.ForeColor);
  Brush BackGroundBrush = new SolidBrush(treeView1.BackColor);
  Brush TextBackGroundBrush = BackGroundBrush;
  float baseX = e.Bounds.Left;
  float baseY = e.Bounds.Top;
  string stringToDraw = tn.Text;
  bool hasParent = (tn.Parent != null);
  bool hasNext = (tn.NextNode != null);
  bool hasPrev = (tn.PrevNode != null);
 
  float strX = baseX;
  float strY = baseY;
  float adjX = ((tn.Level + 1) * 24);
  strX += adjX;
 
  Rectangle UpLine = new Rectangle((int)(strX - 17), (int)(baseY), 2, 8);
  Rectangle DownLine = new Rectangle((int)(strX - 17), (int)(baseY + 8), 2, 8);
  Rectangle ChildBox = new Rectangle((int)(baseX - 16 + adjX + 2), (int)(baseY + 2), 12, 12);
 
  float tailStartX = baseX - 16 + adjX + 2 + 12;
  float tailStartY = baseY + 8;
  if (e.Bounds.Width != 0)
  {
      if ((e.State & TreeNodeStates.Hot) == TreeNodeStates.Hot)
      {//Hot tracking
          DrawFont = new Font(DrawFont, FontStyle.Underline);
      }
      if ((e.State & TreeNodeStates.Selected) == TreeNodeStates.Selected)
      {//change foregroudn/background
      TextBackGroundBrush = new SolidBrush(SystemColors.InactiveBorder);
      if (this.ActiveControl == sender)
      {
        ForeBrush = new SolidBrush(SystemColors.HighlightText);
        TextBackGroundBrush = new SolidBrush(SystemColors.Highlight);
      }
      }
      //// Erase previous
      g.FillRectangle(BackGroundBrush, e.Bounds);
      SizeF stringSize = g.MeasureString(stringToDraw, DrawFont, (int)(e.Bounds.Width - strX), new StringFormat(StringFormatFlags.NoWrap));
      //// Draw the "selected" background
      g.FillRectangle(TextBackGroundBrush, strX, strY, (float)Math.Floor(stringSize.Width), 16F);
      //// Draw the text
      g.DrawString(stringToDraw, DrawFont, ForeBrush, strX, strY);
 
      //// Every node gets a tail sticking out
      g.FillRectangle(Brushes.Black, strX - 17, tailStartY, 16, 2);
      ///////////////////////////////////////////////////////////////////
      if (hasPrev || hasParent) g.FillRectangle(Brushes.Black, UpLine);// Draw up line
      if (hasNext) g.FillRectangle(Brushes.Black, DownLine);// Draw down line
      //// Draw the "+" box
      if (tn.Nodes.Count > 0)
      {
      g.FillRectangle(BackGroundBrush, ChildBox);
      if (!tn.IsExpanded) g.FillRectangle(new SolidBrush(Color.Red), ChildBox);
      g.DrawRectangle(Pens.Black, ChildBox);
      }
  }//end of valid draw region
}