How to use TreeView.AfterSelect and TreeView.DrawNode methods?

Question

I have MyForm.cs, MyForm.Designer.cs files in my project, in MyForm.Designer.cs I did like this:

private System.Windows.Forms.TreeView myTreeView;
this.myTreeView = new System.Windows.Forms.TreeView();
.........
this.myTreeView.AfterSelect += 
                           new TreeViewEventHandler(this.myTreeView_AfterSelect);

in MyForm.cs like this:

private void myTreeView_AfterSelect(object sender, TreeViewEventArgs e)
        {
          //........;
        }

also I have CostumeTreeView class in other files(CostumeTreeView.cs and CostumeTreeView.Designer.cs), in CostumeTreeView.Designer.cs I did like this:

private System.Windows.Forms.TreeView myCostumeTreeView
this.myCostumeTreeView = new System.Windows.Forms.TreeView();
...........
this.myCostumeTreeView.DrawMode = 
                          System.Windows.Forms.TreeViewDrawMode.OwnerDrawAll;
this.myCostumeTreeView.DrawNode += 
               new DrawTreeNodeEventHandler(this.myCostumeTreeView_DrawNode);

in CostumeTreeView.cs :

private void myCostumeTreeView_DrawNode(object sender, DrawTreeNodeEventArgs e)
        {
        ........
            //Here is the problem, myTreeView isn't seen here
            e.Node.Tag = myTreeView.SelectedNode.Text; 
        }

I need when myTreeView's node is selected, all tags in myCostumeTreeView is been changed using after select function (all methods are in one namespace)

Answer 1

If your TreeView controls are on different forms, they either need to reference each other through a form property or an event so that the controls can talk to each other.

The other thing I see is that you probably shouldn't be setting a property in a draw or paint event, which you are doing with e.Node.Tag = myTreeView.SelectedNode.Text; in the DrawNode event. The only thing you should be doing in the DrawNode event is drawing the node, very little else.

To make the reference, your costume form needs a variable and just pass it through the constructor, something like:

private MyForm mainForm;

private CostumeTreeView(MyForm mf) {
  InitializeComponents();
  mainForm = mf;
}

Now you can reference the TreeView control:

private void myCostumeTreeView_DrawNode(object sender, DrawTreeNodeEventArgs e) {
  ........
  e.Node.Tag = mainForm.myTreeView.SelectedNode.Text; 
}

Again, using the DrawNode event to set the tag of the nodes isn't necessary. You are creating a dependency on your GUI, which will make maintenance and debugging difficult in the future.

Answer 2

I think the best option is to acces to the Treeview property present in TreeNode class.

    e.Node.Tag = e.Node.TreeView.SelectedNode.Text; 

You should have acces to it.