List of Windows in vb.net application - vb.net

Question

I have an MDI application where I'm trying to get a list of open windows for a ComponentOne Ribbon Menu. Using VB .NET.
I have this sub for instantiating a new child form within the MDI container:
Private Sub newButton_Click(sender As Object, e As EventArgs) Handles newButton.Click
' Create a new instance of the child form.
Dim ChildForm As New MyProject.MyForm
'Make it a child of this MDI form before showing it.
ChildForm.MdiParent = Me
m_ChildFormNumber += 1
ChildForm.Text = "Window " & m_ChildFormNumber
ChildForm.Show()
End Sub
Then in another Sub for the ribbon menu I try to get the list of windows.
I tried this:
Dim frm As System.Windows.Window
For Each frm In My.Application.Windows
frmButton = New C1.Win.C1Ribbon.RibbonButton(frm.Title)
...
But I get a NullReferenceException on the System.Windows.Window collection.
So then I tried this:
For Each Window In My.Application.Windows
frmButton = New C1.Win.C1Ribbon.RibbonButton(Window.Title)
...
But with that, I get "overload resolution failed because no accessible 'new' can be called without a narrowing conversion" on the arguments for the new RibbonButton. If I turn Option Strict On, of course it says it disallows late binding.
So I guess ultimately I'm wondering why my Windows collection is empty, even if I've opened child forms.
Then even beyond that, why does the New RibbonButton accept frm.Title but not Window.Title.
NOTE (in case you were wondering)...the frmButton is a class object:
Friend WithEvents frmButton As C1.Win.C1Ribbon.RibbonButton
Thank you!

Answer 1

Thanks to clues from multiple sources, I was able to get it working. In case anyone else is wondering how, here's my sample code:
Public Class mainForm
Private m_ChildFormNumber As Integer
Friend WithEvents frmButton As C1.Win.C1Ribbon.RibbonButton
Private Sub newButton_Click(sender As Object, e As EventArgs) Handles newButton.Click
' Create a new instance of the child form.
Dim ChildForm As New ProofOfConcept.FormResize
'Make it a child of this MDI form before showing it.
ChildForm.MdiParent = Me
m_ChildFormNumber += 1
ChildForm.Text = "Window " & m_ChildFormNumber
ChildForm.Show()
End Sub
Private Sub windowMenu_Dropdown(sender As Object, e As EventArgs) Handles windowMenu.DropDown
Dim count As Integer = Me.MdiChildren.Length
windowMenu.Items.ClearAndDisposeItems()
For i As Integer = 0 To count - 1
frmButton = New C1.Win.C1Ribbon.RibbonButton
frmButton.Text = Me.MdiChildren(i).Text
frmButton.Tag = i
If MdiChildren(i) Is ActiveMdiChild Then
frmButton.SmallImage = My.Resources.test
End If
windowMenu.Items.Add(frmButton)
AddHandler frmButton.Click, AddressOf frmButton_Click
Next
End Sub
Private Sub frmButton_Click(sender As Object, e As EventArgs)
Dim Rb As C1.Win.C1Ribbon.RibbonButton = DirectCast(sender, C1.Win.C1Ribbon.RibbonButton)
Me.ActivateMdiChild(MdiChildren(CInt(Rb.Tag)))
Me.MdiChildren(CInt(Rb.Tag)).Focus()
End Sub
End Class

Answer 2

8 years later, this seems to be the only question on how to implement a Window menu, so here's my updated version for the standard MenuStrip control.
Friend WithEvents ChildWindowMenu As ToolStripMenuItem
Private Sub WindowMenu_DropDownOpening(sender As Object, e As EventArgs) Handles windowMenu.DropDownOpening
Try
windowMenu.DropDownItems.Clear()
For Each child In Me.MdiChildren
ChildWindowMenu = New ToolStripMenuItem With {
.Text = child.Text,
.Tag = child
}
If child Is ActiveMdiChild Then
ChildWindowMenu.Checked = True
End If
windowMenu.DropDownItems.Add(ChildWindowMenu)
AddHandler ChildWindowMenu.Click, AddressOf ChildWindowMenu_Click
Next
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub
Private Sub ChildWindowMenu_Click(sender As Object, e As EventArgs)
Try
CType(CType(sender, ToolStripMenuItem).Tag, Form).Activate()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub