[Closed] dotNet Treeview TreeViewNodeSorter Property

Tim,
Everything you need to know including a great example can be found here:

C:\MAXroot\stdplugs\stdscripts\NET_ListViewWrapper.ms

Look for the lines:

view = dotNetClass “System.Windows.Forms.View”
lv.View = view.Details;
sortOrder = dotNetClass “System.Windows.Forms.SortOrder”
lv.Sorting = sortOrder.Ascending;

Mike

Thanks Mike,

I was actually looking through those files last night.

The example you provided is for a listview, and I can’t get it working with a treeview. It errors out with the message:

– Unable to convert: dotNetObject:System.Windows.Forms.SortOrder to type: System.Collections.IComparer

Also the sortOrder will only allow Ascending, Decending and None – I’m not sure you can tell it to sort by imageIndex. http://msdn.microsoft.com/en-us/library/dscy145f.aspx

Either that or I’m missing something?

Tim

Doh. Why did I send you list view info when I meant to send tree view. WTF?!

I meant “C:\maxroot\stdplugs\stdscripts\NET_TreeViewWrapper.ms” around line: #152

sort alphabetically:
http://msdn.microsoft.com/en-us/library/system.windows.forms.treeview.sorted.aspx

or custom sort:
http://msdn.microsoft.com/en-us/library/system.windows.forms.treeview.treeviewnodesorter.aspx

memo to Mike. Must not try and do 5 things at the same time, you will fail.

fn CompileNodeSorterClass forceRecompile:false =
 (
 	if forceRecompile OR dotnetclass "TreeViewTools.NodeSorter" == undefined do
 	(
 		source = ""
 		append source "using System;
"
 		append source "using System.Collections;
"
 		append source "using System.Windows.Forms;
"
 		append source "namespace TreeViewTools
"
 		append source "{
" -- open namespace TreeViewTools
 		append source "public class NodeSorter : IComparer
"
 		append source "{
" -- open class
 		append source "public int Compare(object x, object y)
"
 		append source "{
" -- open method
 		append source "TreeNode tx = x as TreeNode;
"
 		append source "TreeNode ty = y as TreeNode;
"
 		append source "int i = string.Compare(tx.Text, ty.Text);
"
 		append source "if (i == 0) return string.Compare(tx.Text, ty.Text);
"
 		append source "return i;
"
 		append source "}
" -- end method
 		append source "}
" -- end class
 		append source "}
" -- end namespace TreeViewTools
 		csharpProvider = dotnetobject "Microsoft.CSharp.CSharpCodeProvider"
 		compilerParams = dotnetobject "System.CodeDom.Compiler.CompilerParameters"
 		compilerParams.ReferencedAssemblies.Add "System.Windows.Forms.dll"
 		compilerParams.GenerateInMemory = on
 		compilerResults = csharpProvider.CompileAssemblyFromSource compilerParams #(source)
 	)
 	
 	dotnetclass "TreeViewTools.NodeSorter"
 )

that function will compile a custom IComparer class “TreeViewTools.NodeSorter” to do what you want.
Then assign an instance of the class to the tree like so:

tv.TreeViewNodeSorter = dotnetobject "TreeViewTools.NodeSorter"

Thanks so much, Gravey! Very much appreciated.

It looks like that code sorts every node alphabetically and not by imageIndex first.

Would I add a line like this before/after the alphabetical sort?:

append source "int i = Compare(tx.imageIndex, ty.imageIndex);
"

Tim

in your case the comparer has to return (tx.imageIndex – ty.imageIndex);

my bad.
As Denis suggested the line

append source "if (i == 0) return string.Compare(tx.Text, ty.Text);
"

should be:

append source "int i = tx.ImageIndex - ty.ImageIndex;
"

NOTE: you may need to restart max after making the change if it appears not to work

If you’re looking for maximum performance, you might want to replace the Sort functionality altogether. The sorting algorithm on the TreeView is quite simple and not too fast.
It’s not too hard to replace it with the QuickSort implemented by .NET’s List collection, much in the same way as you said in your opening post. That can use a generic IComparer<T> too, so you can define how you want the nodes sorted.

For some more details, check this: http://script.threesixty.nl/outliner/index.php/blog/2011/02/refactoring-the-sort-mode
It’s not too technical in there, nor is there code, but just to illustrate the point

Pjanssen, that sounds really interesting. I had a look through the scripts in your (impessive!) outliner tool, but I could not find any code that relates to “quicksort” as you described.

Gravey and denisT, thanks for the help! I’ve written a very quick test rollout to see if it is working, and whenever I evaluate the script I get the error “–Runtime error: Cannot resolve type: TreeviewTools.nodeSorter”

When I evaluate the line “dotnetClass “TreeViewTools.NodeSorter” it comes up as undefined.

Any ideas what is going wrong? Again, many thanks on the help

--Sort Function
fn CompileNodeSorterClass forceRecompile:false =
 (
 	if forceRecompile OR dotnetclass "TreeViewTools.NodeSorter" == undefined do
 	(
 		source = ""
 		append source "using System;
"
 		append source "using System.Collections;
"
 		append source "using System.Windows.Forms;
"
 		append source "namespace TreeViewTools
"
 		append source "{
" -- open namespace TreeViewTools
 		append source "public class NodeSorter : IComparer
"
 		append source "{
" -- open class
 		append source "public int Compare(object x, object y)
"
 		append source "{
" -- open method
 		append source "TreeNode tx = x as TreeNode;
"
 		append source "TreeNode ty = y as TreeNode;
"
 		append source "int i = string.Compare(tx.Text, ty.Text);
"
 		--append source "if (i == 0) return string.Compare(tx.Text, ty.Text);
"
		append source "int i = tx.ImageIndex - ty.ImageIndex;
"
 		append source "return i;
"
 		append source "}
" -- end method
 		append source "}
" -- end class
 		append source "}
" -- end namespace TreeViewTools
 		csharpProvider = dotnetobject "Microsoft.CSharp.CSharpCodeProvider"
 		compilerParams = dotnetobject "System.CodeDom.Compiler.CompilerParameters"
 		compilerParams.ReferencedAssemblies.Add "System.Windows.Forms.dll"
 		compilerParams.GenerateInMemory = on
 		compilerResults = csharpProvider.CompileAssemblyFromSource compilerParams #(source)
 	)
 	dotnetClass "TreeViewTools.NodeSorter"
 )

--Rollout
rollout test "Test Rollout" (
	dotNetControl tv "Treeview" width:180 height:190
	on test open do (
		tv.sorted = true
		CompileNodeSorterClass()
		tv.TreeViewNodeSorter = dotnetObject "TreeViewTools.NodeSorter"
		tv.sort()
	)
)
createDialog test 200 200


newNode = test.tv.nodes.add "a1"
newNode.name = "a1"
newNode.imageIndex = 1

newNode = test.tv.nodes.add "a2"
newNode.name = "a2"
newNode.imageIndex = 1

newNode = test.tv.nodes.add "b1"
newNode.name = "b1"
newNode.imageIndex = 0

newNode = test.tv.nodes.add "b2"
newNode.name = "b2"
newNode.imageIndex = 0