Displaying a recursive binary tree

Hi Guys,
I've made some progress. I went down the path of creating my own structure, but it became messy and slow very quickly. I've gone with the option of having just a simple array to hold the data, and labels in a table layoput panel. It works quite well, and resizes nicely. Event handeling is working, I have bretty much done what I need to do except for the connections lines.
My issue is that when I paint the lines they end up under the controls. I've tried a couple of diferent methods I've found on the web but cant get them to work as I'd expect them to. The only luck I've had is with drawing directly to the desktop. It seems mesy though, the lines dissapear again whenever the mouse is moved, and it's out of whack because the control positions that I use to get my drawing point are relative to the form, and not the screen.
I hope someone can give me some advise please on how to get my lines on top of all the labels, while still being able to handel click events.
thanks verry much as always.
rgds
Tim
P.S. I've attached what I have so far.
 

I think you have the right idea, but it would be more like
void Draw(Graphics g)
{
   // do drawing here
}
This would only get called on the OnPaint event handler of your form.
foreach (Node node in Nodes)
{
    node.Draw(g);
}
 
This would just handle drawing though.  To handle click and edit, you probably want to maintain the coordinates and extents of all nodes in your node class and in the leftmousedown button cycle through the nodes and check if any of the nodes were clicked.  If you find a node that is inside the mouse coordinates, then move an invisible textbox into the node and then turn it visible so you can edit the name.
-Mike

After having another think about GDI+ a bit more I'v had a bit of a noob epiphany and another piece of the puzzle has fit together. Every control that I've been using would use GDI+ to display itself or something similar. So I should just build my own node control to hold the data and display it in a position relative to the parent node with a connecting line between them. I've been playing around with drawing to the screen from a form and have figured that bit out. But how do i get the graphics object to draw to from a class. e.g. this is what i have to hold the data in a tree structure (not really tested yet and needs othe changes).

using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
namespace TestApplication
{
    class TreeNode
    {
        private TreeNode leftBranch;
        private TreeNode rightBranch;
        private string storedValue;

        public TreeNode(string valueToStore)
        {
            storedValue = valueToStore;
        }
        public void addLeftBranch(string valueToStore)
        {
            leftBranch = new TreeNode(valueToStore);
        }
        public void addRightBranch(string valueToStore)
        {
            rightBranch = new TreeNode(valueToStore);
        }
        public void show()
        {
            //do drawing here and call the childrens show()
        }
    }
}
 
Have i got the right idea? I dont know how I would get the paint event to get the graphics object from to draw on. I want to do this in the node class as i just want to call its show() and have it populate any child nodes itself and display them. So in the form i would just do something like this;

TreeNode node = new Node(34123);

it would then use that entity id and check if the entity has children, if so add the children to the node, the children would do the same and so on untill there are no more children. Then I would call the show();

node.show()

it would then draw the name of the entity, call its childrens draw() to do the same and so on.
 
I hope i am not getting more lost.
 
 

Hi Mike,
Thanks heaps for your comments. Unfortunately I've already put 200+ hrs into this application so I'll have to stick with win forms, however I might consider WPF for my next project. Haven't used GDI+ before, I just read quite a lenghty article on it and it seems like it will meet my needs. But it did remind me of one more thing the view needs to be able to do. You need to be able to click on a node, and have a cursor appear so you can type in some text. Thats how all the names get there to start off with. Can that also be done with GDI+?
Thanks Mike
Tim

I would probably answer this by saying you probably don't want to build this in Windows Forms unless its a pure GDI+ application.  WPF is much more suited for building custom controls (even out of existing tree controls).  If you do this in GDI+ then it shouldn't be too bad in Windows Forms, you would just need to handle left mouse down and possibly offsets in scrolling.  In WPF (or even in Silverlight), this should be pretty easy with the existing TreeView Control and a Hierarchal DataTemplates.  You can bind a view model containing your data structure and should be able to make this happen.  Each node can be a textblock that has a click event.  The TextBlock would be contained in your DataTemplate.