I have 10 `Textboxs` then I tried to set background color to red color to all `Textbox` which is blank leaves, it's work but it doesn't set background color by order from first `Textbox` to tenth `Textbox`, I tried to set `TabIndex` too. But it is still doesn't work.

```
#Region "Method"

    Private Function pf_validate_ok()
        For Each tb In Panel1.Controls
            If TypeOf tb Is DevExpress.XtraEditors.TextEdit Then
                If tb.Text = String.Empty Then

                    tb.BackColor = Color.Red
                    tb.ForeColor = Color.White

                    Return False
                Else
                    tb.BackColor = Color.White
                    tb.ForeColor = Color.Black
                End If
            End If
        Next tb
        Return True
    End Function

#End Region

```