We also override the OnClick method. The DataWindow control doesn't natively support a click-on-column header sort operation. The overridden method uses the PFC click-on-column header code modified to work in a .NET environment.

OnClick

Protected Overrides Sub OnClick
(ByVal e As EventArgs)
Dim clickedobject As Sybase.DataWindow.ObjectAtPointer
Dim objectname, columnname, sort As String
clickedobject = MyBase.ObjectUnderMouse()
Select Case clickedobject.Band.Type
  Case Sybase.DataWindow.BandType.Header
  objectname = clickedobject.Gob.Name
   If objectname.Substring(objectname
    .Length() - 2, 2) = "_t" Or _
    objectname.Substring(objectname.
    Length() - 2, 2) = "_a" Then
    columnname = objectname.Sub
    string(0, objectname.Length() - 2)
    If columnname = sortcolumnname
   Then
   If sortorder = " A" Then
    sortorder = " D"
   Else
    sortorder = " A"
    End If
   Else
    sortcolumnname = columnname
    sortorder = " A"
   End If
   sort = sortcolumnname + sortorder
   MyBase.SetSort(sort)
   MyBase.Sort()
  End If
End Select
MyBase.OnClick(e)
End Sub

One of the main reasons for overriding the DataWindow control - other than to get it not to move when the title bar is shown - is because the DataWindow object color properties take RGB values. The system color values in the .NET framework are ARGB values (they contain an alpha component). The GetRGB method that I added converts the ARGB value to an RGB value that the DataWindow can use.

GetRGB

Public Function GetRGB(ByVal theColor As Color) As String
Dim theRGB As Long
theRGB = RGB(theColor.R(), theColor.G(), theColor.B())
Return theRGB.ToString()
End Function

The color setting methods I've added to the subclassed control accept .NET system colors and call that method internally to convert the value and then set the appropriate DataWindow object property. One example of this is the SetColumnBackColor method; the other color setting methods are similar.

SetColumnBackColor

Public Sub SetColumnBackColor
   (ByVal theColor As Color)
Dim columns As ArrayList = GetVisibleColumns()
Dim col As String
For Each col In columns
   MyBase.SetProperty(obj + ".BackGround.Mode", "0")
   MyBase.SetProperty(col + ".Background.Color", GetRGB(theColor))
Next
End Sub

One of the color settings that the DataWindow control doesn't provide native support for is to have alternating rows appear with different background colors. That's done easily enough by adding a property expression to the DataWindow object and I've added a method to the overridden control to make it simpler.

SetRowAlternatingColors

Public Sub SetRowAlternating
Colors(ByVal OddColor As Color, ByVal EvenColor As Color)
Dim columns As ArrayList = GetVisibleColumns()
Dim col, modify As String
Dim rc As Int32
modify = GetRGB(OddColor) + _~tif ( MOD( getrow(),2 )=0 ," +
GetRGB(EvenColor) + "," + GetRGB(OddColor) + ")"
For Each col In columns
   MyBase.SetProperty(obj + ".BackGround.Mode", "0")
   rc = MyBase.SetProperty(col + ".Background.Color", modify)
Next
End Sub

Similar to the issues with the .NET system colors, the .NET Framework Font is a class whereas the DataWindow has a series of independent font properties. The Font setting methods I've added to the subclassed DataWindow control accept the .NET Framework Font class and then access the individual properties. One example is the SetColumnFont method; the other font setting methods are similar.

SetColumnFont

Public Sub SetColumnFont(ByVal theFont As Font)
Dim columns As ArrayList = GetVisibleColumns()
Dim col As String
For Each col In columns
   MyBase.SetProperty(col + ".Font.Face", theFont.Name)
   MyBase.SetProperty(col + ".Font.Height", "-" + theFont.Size.ToString())
Next
End Sub

There are some helper functions defined for the subclassed control as well. One is the GetHeaderObjects method. It looks through all of the controls on the DataWindow object and determines which are static text controls in the header band.

GetHeaderObjects

Public Function GetHeaderObjects() As ArrayList
Dim objects, obj As String
Dim objarray As String()
Dim headerobjects As New ArrayList
objects = MyBase.GetProperty ("DataWindow.Objects")
objarray = objects.Split(vbTab.ToCharArray())
For Each obj In objarray
  If MyBase.GetProperty(obj + ".Type") = "text" Then
   If MyBase.GetProperty(obj + ".Band") = "header" Then
    headerobjects.Add(obj)
   End If
  End If
Next
Return headerobjects
End Function

A somewhat similar approach is used by the GetColumns method to get an array containing all of the columns in the DataWindow object.

GetColumns

Public Function GetColumns() As ArrayList
Dim i, j As Int16
j = MyBase.ColumnCount()
Dim columns As New ArrayList
Dim columnname As String
For i = 1 To j
  columnname = MyBase.GetProperty("#" + i.ToString() + ".Name")
  columns.Add(columnname)
Next
Return columns
End Function