vb.net - Problème Treeview.DrawNode

Bonjour à tous,

Je rencontre un curieux problème dans l'événement Treeview.DrawNode.
J'ai recopié et modifié ce code qui fonctionne parfaitement :

Code:

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Imports System
Imports System.Drawing
Imports System.Windows.Forms
 
Public Class TreeViewOwnerDraw
    Inherits Form
 
    Private WithEvents myTreeView As TreeView
 
    ' Create a Font object for the node tags.
    Private NodeFont As New Font("Arial", 9.0!)
 
    Public Sub New()
 
        ' Create and initialize the TreeView control.
        myTreeView = New TreeView()
        myTreeView.Dock = DockStyle.Fill
        myTreeView.ShowLines = False
 
        ' Add nodes to the TreeView control.
        Dim node As TreeNode
        Dim x As Integer
        For x = 1 To 3
 
            ' Add a root node to the TreeView control.
            node = myTreeView.Nodes.Add(String.Format("Task {0}", x))
            Dim y As Integer
            For y = 1 To 3
 
                ' Add a child node to the root node.
                node.Nodes.Add(String.Format("Subtask {0}", y))
            Next y
        Next x
 
        myTreeView.DrawMode = TreeViewDrawMode.OwnerDrawText
        AddHandler myTreeView.MouseDown, AddressOf myTreeView_MouseDown
 
        Me.Controls.Add(myTreeView)
 
    End Sub 'New
 
    <STAThreadAttribute()> _
    Shared Sub Main()
        Application.Run(New TreeViewOwnerDraw())
    End Sub 'Main
 
    ' Draws a node.
    Private Sub myTreeView_DrawNode(ByVal sender As Object, _
        ByVal e As DrawTreeNodeEventArgs) Handles myTreeView.DrawNode
 
        Dim NodeImgColl As Image = Image.FromFile("C:\DotNet\FED v6.0\FED v1.0\Resources\Arbo+.gif")
        Dim NodeImgExp As Image = Image.FromFile("C:\DotNet\FED v6.0\FED v1.0\Resources\Arbo-.gif")
        Dim x As Integer = e.Node.Bounds.Left - 16
        Dim y As Integer = e.Node.Bounds.Top + 1
 
        ' Dessin du Noeud + Texte
        If e.Node.Level <> 1 Then
            If e.Node.IsExpanded Then
                e.Graphics.DrawImage(NodeImgExp, x, y, 12, 12)
            Else
                e.Graphics.DrawImage(NodeImgColl, x, y, 12, 12)
            End If
        End If
 
        ' Draw the background and node text for a selected node.
        If (e.State And TreeNodeStates.Selected) <> 0 Then
 
            ' Draw the background of the selected node. The NodeBounds
            ' method makes the highlight rectangle large enough to
            ' include the text of a node tag, if one is present.
            e.Graphics.FillRectangle(Brushes.White, e.Node.Bounds)
 
 
            ' Draw the node text.
            e.Graphics.DrawString(e.Node.Text, NodeFont, Brushes.Gray, e.Bounds.Left - 2, e.Bounds.Top)
 
            ' Use the default background and node text.
        Else
            e.Graphics.DrawString(e.Node.Text, NodeFont, Brushes.Black, e.Bounds.Left - 2, e.Bounds.Top)
        End If
 
    End Sub 'myTreeView_DrawNode
 
    Private Sub myTreeView_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs)
        Dim clickedNode As TreeNode = myTreeView.GetNodeAt(e.X, e.Y)
        If Not IsNothing(clickedNode) Then
            If NodeBounds(clickedNode).Contains(e.X, e.Y) Then
                myTreeView.SelectedNode = clickedNode
            End If
        End If
    End Sub
 
    Private Function NodeBounds(ByVal node As TreeNode) As Rectangle
 
        ' Set the return value to the normal node bounds.
        Dim bounds As Rectangle = node.Bounds
 
        Return bounds
    End Function
 
End Class

Mais je souhaiterais ajouter manuellement le Treeview et y ajouter le code afin d'obtenir le même rendu :

Code:

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Imports System
Imports System.Drawing
Imports System.Windows.Forms
 
Public Class Form1
 
    Private NodeFont As New Font("Arial", 9.0!)
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
        ' Create and initialize the TreeView control.
 
        myTreeView.ShowLines = False
 
        ' Add nodes to the TreeView control.
        Dim node As TreeNode
        Dim x As Integer
        For x = 1 To 3
 
            ' Add a root node to the TreeView control.
            node = myTreeView.Nodes.Add(String.Format("Task {0}", x))
            Dim y As Integer
            For y = 1 To 3
 
                ' Add a child node to the root node.
                node.Nodes.Add(String.Format("Subtask {0}", y))
            Next y
        Next x
 
        myTreeView.DrawMode = TreeViewDrawMode.OwnerDrawText
 
    End Sub
 
 
    ' Draws a node.
    Private Sub myTreeView_DrawNode(ByVal sender As Object, ByVal e As DrawTreeNodeEventArgs) Handles myTreeView.DrawNode
 
        Dim NodeImgColl As Image = Image.FromFile("C:\DotNet\FED v6.0\FED v1.0\Resources\Arbo+.gif")
        Dim NodeImgExp As Image = Image.FromFile("C:\DotNet\FED v6.0\FED v1.0\Resources\Arbo-.gif")
        Dim x As Integer = e.Node.Bounds.Left - 16
        Dim y As Integer = e.Node.Bounds.Top + 1
 
        ' Dessin du Noeud + Texte
        If e.Node.Level <> 1 Then
            If e.Node.IsExpanded Then
                e.Graphics.DrawImage(NodeImgExp, x, y, 12, 12)
            Else
                e.Graphics.DrawImage(NodeImgColl, x, y, 12, 12)
            End If
        End If
 
        ' Draw the background and node text for a selected node.
        If (e.State And TreeNodeStates.Selected) <> 0 Then
 
            ' Draw the background of the selected node. The NodeBounds
            ' method makes the highlight rectangle large enough to
            ' include the text of a node tag, if one is present.
            e.Graphics.FillRectangle(Brushes.White, e.Node.Bounds)
 
 
            ' Draw the node text.
            e.Graphics.DrawString(e.Node.Text, NodeFont, Brushes.Gray, e.Bounds.Left - 2, e.Bounds.Top)
 
            ' Use the default background and node text.
        Else
            e.Graphics.DrawString(e.Node.Text, NodeFont, Brushes.Black, e.Bounds.Left - 2, e.Bounds.Top)
        End If
 
    End Sub 'myTreeView_DrawNode
 
    Private Sub myTreeView_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs) Handles myTreeView.MouseDown
        Dim clickedNode As TreeNode = myTreeView.GetNodeAt(e.X, e.Y)
        If Not IsNothing(clickedNode) Then
            If NodeBounds(clickedNode).Contains(e.X, e.Y) Then
                myTreeView.SelectedNode = clickedNode
            End If
        End If
    End Sub
 
    Private Function NodeBounds(ByVal node As TreeNode) As Rectangle
 
        ' Set the return value to the normal node bounds.
        Dim bounds As Rectangle = node.Bounds
 
        Return bounds
    End Function
 
End Class

La seule différence est donc que dans le 1er cas le TreeView est généré par code tandis que dans le second cas il est mis à la main (avec le même nom.)

CEPENDANT, dans cette dernière configuration, lorsque je clique sur le "+" du second noeud (ou du 3ème...), le nom "SubTask2" vient s'inscrire sous le "+" du premier noeud...
Et le problème disparait si je mets myTreeView.ExpandsAll() dans mon code juste après avoir rempli le TreeView...

Merci de votre aide.