Is there a technique to centre a ListBox column heading and AlignRight the contents of same column

Getting Started
1

I wonder how I might go about centering the heading of a ListBox column and yet have the contents of that same column aligned right. I cannot find if it is possible to distinguish between the column header and the contents.

2

Web or desktop?

3

Set the ListBox without Header.

Place a Canvas (a serie of Canvas) above the ListBox and draw the header by yourself (in the Canvas).

this is the common answer usually sent to these questions…

4

Align the column itself with ColumnAlign and then align each cell with CellAlign as they are added.

5

Subclass listbox and add these properties:

Private mColumnAlignment() As Integer Private mHeaderAlignment() As Integer Private mHeaderAlignmentAll As Integer
Then add methods to access them:

[code]Sub ColumnAlignment(index As Integer, Assigns value As Integer)
ReDim mColumnAlignment(ColumnCount - 1)
mColumnAlignment(index) = value
Invalidate()
End Sub

Function ColumnAlignment(index As Integer) As Integer
ReDim mColumnAlignment(ColumnCount - 1)
Return mColumnAlignment(index)
End Function

Sub HeaderAlignment(index As Integer, Assigns value As Integer)
ReDim mHeaderAlignment(ColumnCount - 1)
ReDim mColumnAlignment(ColumnCount - 1)
If index = -1 Then
mHeaderAlignmentAll = value
For i As Integer = 0 To ColumnCount - 1
Super.ColumnAlignment(i) = value
Next
Else
Super.ColumnAlignment(index) = value
mHeaderAlignment(index) = value
End
Invalidate()
End Sub

Function HeaderAlignment(index As Integer) As Integer
ReDim mHeaderAlignment(ColumnCount - 1)
If index = -1 Then
Return mHeaderAlignmentAll
Else
Return mHeaderAlignment(index)
End
End Function[/code]
This is the CellTextPaint event handling:

Function CellTextPaint(g As Graphics, row As Integer, column As Integer, x as Integer, y as Integer) As Boolean Dim text As String = Cell(row, column) Select Case mColumnAlignment(column) Case Listbox.AlignLeft x = 0 Case Listbox.AlignCenter Dim blankWidth As Integer = g.Width - g.StringWidth(text) If (blankWidth / 2) < 2 Then x = 0 Else x = blankWidth / 2 - 2 End Case Listbox.AlignRight Dim blankWidth As Integer = g.Width - g.StringWidth(text) If (blankWidth / 2) < 2 Then x = 0 Else x = blankWidth - 4 End Else // TODO: Listbox.AlignDefault and Listbox.AlignDecimal End g.DrawString(text, x, y, g.Width - 4, True) Return True End Function
Use it like this:

[code]Sub Open()
Me.HasHeading = True
Me.ColumnsResizable = True

Me.ColumnCount = 4

Me.ColumnAlignment(0) = Listbox.AlignLeft
Me.ColumnAlignment(1) = Listbox.AlignCenter
Me.ColumnAlignment(2) = Listbox.AlignRight

Me.HeaderAlignment(-1) = Listbox.AlignCenter

// or set each header alignment separately
// Me.HeaderAlignment(0) = Listbox.AlignLeft
// Me.HeaderAlignment(1) = Listbox.AlignCenter
// Me.HeaderAlignment(2) = Listbox.AlignRight

Me.Heading(0) = “AlignLeft”
Me.Heading(1) = “AlignCenter”
Me.Heading(2) = “AlignRight”

Me.AddRow(“ABC”, “ABC”, “ABC”)
Me.AddRow(“x”, “x”, “x”)
Me.AddRow(“123456”, “123456”, “123456”)

End Sub
[/code]
Notes:

  • Listbox.AlignDefault and Listbox.AlignDecimal are not handled in the CellTextPaint event
  • CellAlignment is not handled in the CellTextPaint.
6

Thanks for the replies. I will try out the different solutions. I particularly like Eli’s, as it gives me some more experience with OOP (I think?).