TableLayoutPanel add Controls not visible - vb.net

Question

I am trying to dynamically add images to a TableLayoutPanel. The add appears to work, when I look at the contents of the control, the new items appear to have been added. The RowCount = 10, the IEnumerable has 18 items that contain the controls I have added.
My problem is, is that when the form is shown, only the first row is visible. I cannot dynamically set the Visible property to True on anything, the instruction is ignored. What am I missing?
Code:
Private Sub LoadTable()
' get the width in pixels of the columns
Dim oSizeType As SizeType = TableLayoutPanel1.ColumnStyles(0).SizeType
Dim Width As Single
Select Case oSizeType
Case SizeType.Percent, SizeType.AutoSize
Width = TableLayoutPanel1.Width / TableLayoutPanel1.ColumnCount
Case SizeType.Absolute
Width = TableLayoutPanel1.ColumnStyles(0).Width
End Select
' Fix the height of the rows
Dim Height As Single = Width
Dim oPicture As New PictureBox
Dim Cols As Integer = 1
Dim Rows As Integer = -1
Dim Cell As String = String.Empty
' loop through all the images from the folder
For i As Integer = 0 To m_FileList.Count - 1
' establish the current row/column in the table
Dim j As Integer = i + 1
'MsgBox(Fix(j / 2))
If Fix(j / 2) <> CDbl(j / 2) Then
Cols = 0
Rows += 1
' add a row if we have moved to the next row
If Rows > 0 Then TableLayoutPanel1.RowStyles.Add(New RowStyle(SizeType.Absolute, Height))
' this doesn't happen automatically
TableLayoutPanel1.RowCount = Rows + 1
Else
Cols = 1
End If
' this is used for the name of some controls
Cell = "R" & Rows & "C" & Cols
' now scale the image to fit into the Table Cells
Dim oPictureBox As New PictureBox
oPictureBox.Height = Height
oPictureBox.Width = Width
Dim oImage As Bitmap = New Bitmap(Bitmap.FromFile(CType(m_FileList.Item(i).Value, String)))
' set the PictureBox properties
oPictureBox.BackgroundImageLayout = ImageLayout.Stretch
oPictureBox.BorderStyle = BorderStyle.Fixed3D
' scale the image to the PictureBox size
'Dim oResized As Image = New Bitmap(Bitmap.FromFile(CType(oPictureBox.Tag, String)))
'ImageEdit.ResizeImage(oImage, oResized, picEnlargement.Width, picEnlargement.Height, False)
ScaleImage(oPictureBox, oImage)
' set the Image of the PictureBox
oPictureBox.Image = oImage
oPictureBox.Name = "PictureBox" & i
' get the path of the current file
Dim f As String = m_FileList(i).Value
'set the properties of the new controls
Dim t As String = GetTitle(f)
'oLabel.Text = t
'oLabel.AutoSize = True
'oLabel.Location = New System.Drawing.Point(30, 110)
oPicture = New PictureBox
With oPicture
SetToolTip(oPicture, f)
oPicture.Tag = f
.Image = oPictureBox.Image
.Dock = DockStyle.Fill
.Size = New System.Drawing.Size(100, 100)
.SizeMode = PictureBoxSizeMode.StretchImage
.Location = New System.Drawing.Point(2, 2)
.Cursor = Cursors.Hand
.Name = "PictureBox" & i + 1
.Visible = True
End With
'here we add the controls to a layout panel to
'manage the positioning of the controls
Dim oContainer As New Panel
With oContainer
.Dock = DockStyle.Fill
.Margin = New System.Windows.Forms.Padding(0)
.Controls.Add(oPicture)
'.Controls.Add(oLabel)
.MaximumSize = New Size(Height, Width)
.MinimumSize = New Size(Height, Width)
.Name = "Container_" & Cell
.Visible = True
End With
' add the
TableLayoutPanel1.Controls.Add(oContainer, Cols, Rows)
'TableLayoutPanel1.SetRow(oContainer, Rows)
'TableLayoutPanel1.SetColumn(oContainer, Cols)
TableLayoutPanel1.Controls.Item(i).Name = "Control_" & Cell
TableLayoutPanel1.Controls.Item(i).Enabled = True
TableLayoutPanel1.Controls.Item(i).Visible = True
'here we add a handler for the picture boxs click event
AddHandler oPicture.Click, AddressOf oPictureClickEvent
Next
TableLayoutPanel1.Visible = True
For i As Integer = 0 To TableLayoutPanel1.Controls.Count - 1
TableLayoutPanel1.Controls(i).Enabled = True
TableLayoutPanel1.Controls(i).Visible = True
Next
End Sub

Answer 1

What was missing was setting the TableLayoutPanel Height. After adding the controls, you need to adjust the Height of the table to a multiple of the height of the rows * (number of rows - 1), that's the basic requirement, but needs a tweak to stop the last row being stretched...
Private Sub LoadTable()
Dim oPictures As Control() = {}
'Dim oTableLayoutPanel As New TableLayoutPanel
' get the width in pixels of the columns
Dim oSizeType As SizeType = TableLayoutPanel1.ColumnStyles(0).SizeType
Dim Width As Single
Select Case oSizeType
Case SizeType.Percent, SizeType.AutoSize
Width = TableLayoutPanel1.Width / TableLayoutPanel1.ColumnCount
Case SizeType.Absolute
Width = TableLayoutPanel1.ColumnStyles(0).Width
End Select
' Fix the height of the rows
Dim Height As Single = Width
Dim oPicture As New PictureBox
Dim Cols As Integer = 1
Dim Rows As Integer = -1
Dim Cell As String = String.Empty
TableLayoutPanel1.RowCount = Fix(m_FileList.Count / 2)
' loop through all the images from the folder
For i As Integer = 0 To m_FileList.Count - 1
' establish the current row/column in the table
Dim j As Integer = i + 1
'MsgBox(Fix(j / 2))
If Fix(j / 2) <> CDbl(j / 2) Then
Cols = 0
Rows += 1
' add a row if we have moved to the next row
TableLayoutPanel1.RowStyles.Add(New RowStyle(SizeType.Absolute, Height))
' this doesn't happen automatically
TableLayoutPanel1.RowCount = Rows + 1
Else
' this line should never be needed but just in case
If Rows < 0 Then Rows = 0
Cols = 1
End If
' this is used for the name of some controls
Cell = "R" & Rows & "C" & Cols
'--------------------------------------------
' set up the PictureBox
'--------------------------------------------
Dim oPictureBox As New PictureBox
' get the path of the current file
Dim f As String = m_FileList(i).Value
'set the properties of the new controls
Dim t As String = GetTitle(f)
' create the PictureBox
With oPictureBox
.Height = Height
.Width = Width
' load the image from the current file path
Dim oImage As Bitmap = New Bitmap(Bitmap.FromFile(CType(m_FileList.Item(i).Value, String)))
' set the PictureBox properties
.BackgroundImageLayout = ImageLayout.Stretch
.BorderStyle = BorderStyle.Fixed3D
' scale the image to the PictureBox size
ScaleImage(oPictureBox, oImage)
' set the Image of the PictureBox
.Image = oImage
.Name = "PictureBox" & i + 1
.Dock = DockStyle.Fill
.Size = New System.Drawing.Size(Height, Width)
.SizeMode = PictureBoxSizeMode.StretchImage
.Location = New System.Drawing.Point(0, 0)
.Cursor = Cursors.Hand
.Visible = True
.Enabled = True
' set the Tag to the filepath of the image
.Tag = f
' set the ToolTip for the PictureBox
' This becomes the "Title" from the File MetaData
SetToolTip(oPictureBox, f)
'here we add a handler for the PictureBox click event
AddHandler oPictureBox.Click, AddressOf PictureClickEvent
End With
oPictures.Add(oPictureBox)
Next
' now add the picturebox to the next cell addres
With TableLayoutPanel1
' add the
.Controls.AddRange(oPictures)
'.Controls.Add(oPictureBox, Cols, Rows)
'.SetRow(oPictureBox, Rows)
'.SetColumn(oPictureBox, Cols)
'.Controls.Item(i).Name = "Control_" & Cell
'.Controls.Item(i).Enabled = True
'.Controls.Item(i).Visible = True
End With
TableLayoutPanel1.Visible = True
For i As Integer = 0 To TableLayoutPanel1.Controls.Count - 1
TableLayoutPanel1.Controls(i).Enabled = True
TableLayoutPanel1.Controls(i).Visible = True
Next
' adjust the height of the table to a multiple of the number of new rows * the Height of each row
TableLayoutPanel1.Height = (TableLayoutPanel1.RowCount - 1) * Height
' set the TableLayoutPanel properties
TableLayoutPanel1.Dock = DockStyle.Top
TableLayoutPanel1.AutoSize = False
TableLayoutPanel1.Visible = True
TableLayoutPanel1.Enabled = True
TableLayoutPanel1.Focus()
TableLayoutPanel1.Parent = Me.Panel1
End Sub