VB.NET Tab Control pause drawing while changing tabs - vb.net

Question

I have a tab control with 5 tabs on it. Each tab has a large number of individual controls on it. (Ranging from 3 to 70 controls, all standard checkboxes, textboxes, comboboxes and radiobuttons.)
When running, the drawing seems to freeze mid-way through changing tabs. So you end up with part of the old tab's controls along with part of the new tab's controls drawn together.
I'd like to be able to stop drawing until all the controls are fully loaded and the code has finished running the "scoring" code.
I have tried using Suspend/Resume Layout on both the tab control and individual pages, but it does not seem to have any affect on drawing.
I have also tried using a custom class I found while searching for an answer, but it either doesn't pause the drawing or it causes the form to become unstable visually.
Imports System.Runtime.InteropServices
Friend Class DrawingControl
<DllImport("user32.dll")>
Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal wMsg As Int32, ByVal wParam As Boolean, ByVal lParam As Int32) As Integer
End Function
Private Const WM_SETREDRAW As Integer = 11
Public Shared Sub SuspendDrawing(ByVal parent As Control)
SendMessage(parent.Handle, WM_SETREDRAW, False, 0)
End Sub
Public Shared Sub ResumeDrawing(ByVal parent As Control)
SendMessage(parent.Handle, WM_SETREDRAW, True, 0)
parent.Refresh()
End Sub
End Class
*** EDIT 11/22/2019: Adding the "Scoring" code that runs when changing tabs
Here is the sequence of events that run when changing tabs:
1) TabControl Deselecting
Private Sub tabDetails_Deselecting(sender As Object, e As TabControlCancelEventArgs) Handles tabDetails.Deselecting
tabDetails.SuspendLayout()
pgAcademic.SuspendLayout()
pgBusiness.SuspendLayout()
pgLIS.SuspendLayout()
pgPatient.SuspendLayout()
pgRegulatory.SuspendLayout()
End Sub
2) TabControl Selected - No code here - However, it's after THIS that the tabs become "combined" with the outlines of controls from each tab.
3) TabControl Index Change
Private Sub tabDetails_SelectedIndexChanged(sender As Object, e As EventArgs) Handles tabDetails.SelectedIndexChanged
Dim pg As Integer = Me.tabDetails.SelectedIndex
Select Case pg
Case 0
Me.txtPageScore.Text = score_pgPatientCare
Case 1
Me.txtPageScore.Text = score_pgBusiness
Case 2
Me.txtPageScore.Text = score_pgLIS
Case 3
Me.txtPageScore.Text = score_pgAcademic
Case 4
Me.txtPageScore.Text = score_pgRegulatory
End Select
End Sub
4) Step 3 fires this code:
Private Sub UpdateScore()
Dim intTotalScore As Integer = Vars.intNewScore 'Max Score = 708
Dim intScore As Integer = 0
If Vars.DisableEvents Then Exit Sub
Vars.DisableEvents = True
score_pgPatientCare = Scoring.UpdateScore(Me.pgPatient)
score_pgBusiness = Scoring.UpdateScore(Me.pgBusiness)
score_pgLIS = Scoring.UpdateScore(Me.pgLIS)
score_pgAcademic = Scoring.UpdateScore(Me.pgAcademic)
score_pgRegulatory = Scoring.UpdateScore(Me.pgRegulatory)
intTotalScore += (score_pgPatientCare + score_pgBusiness + score_pgLIS + score_pgAcademic + score_pgRegulatory)
Using dbTPT As New BGL_ApplicationsEntities
'** Use this area if needing to calculate more than YES/NO
'**********************
'*** Patient Care ***
'**********************
If chkPatientCare_IRB.Checked Then
If Not txtPatientCare_IRB.Text.Trim = "" Then
Dim propertyName = "PatientCare_IRB_Approved"
intScore = CType(weightSettings.Items.Item(propertyName), Integer)
score_pgPatientCare += intScore
intTotalScore += intScore
End If
End If
'**********************
'*** Business ***
'**********************
If chkBusiness_Replace.Checked Then
If chkBusiness_Outdated.Checked Or
chkBusiness_Inferior.Checked Or
chkBusiness_Savings.Checked Then
intScore = 0
Dim propertyName = "Business_Replace_Just"
intScore = CType(weightSettings.Items.Item(propertyName), Integer)
score_pgBusiness += intScore
intTotalScore += intScore
End If
End If
End Using
ssLabel.Text = "Total Score: " + intTotalScore.ToString
custProgBar.Value = intTotalScore
Dim pg As Integer = Me.tabDetails.SelectedIndex
Select Case pg
Case 0
Me.txtPageScore.Text = score_pgPatientCare
Case 1
Me.txtPageScore.Text = score_pgBusiness
Case 2
Me.txtPageScore.Text = score_pgLIS
Case 3
Me.txtPageScore.Text = score_pgAcademic
Case 4
Me.txtPageScore.Text = score_pgRegulatory
End Select
Vars.DisableEvents = False
End Sub
5) The above code fires this code for each tab:
Module Scoring
Public Function UpdateScore(ByVal tab As TabPage) As Integer
Dim intPgScore As Integer = 0
Dim intScore As Integer = 0
Dim intMult As Integer = 0
Dim arrPropName() As String
Dim strPropName As String
Dim strYesNo As String = Nothing
'If Vars.DisableEvents Then Return 0
'Vars.DisableEvents = True
Using dbTPT As New BGL_ApplicationsEntities
If tab.Name = "pgPatient" Then
For Each pan In tab.ChildControls(Of Panel)
If pan.Name.ToString.Substring(0, 6) = "chkgrp" Then
Dim cuScores() As Integer = {0, 0, 0, 0, 0}
Dim i As Integer = 0
For Each chk As CheckBox In pan.ChildControls(Of CheckBox)
If chk.Checked Then
arrPropName = Split(chk.Name.Replace("chk", "").Replace("CU", "PatientCare"), "_")
strPropName = arrPropName(0) + "_" + arrPropName(1)
Dim w = dbTPT.tbl_Weights.FirstOrDefault(Function(n) n.Weight_Name = strPropName)
If w IsNot Nothing Then
intScore = CType(frmNewProject.weightSettings.Items.Item(arrPropName(0) + "_" + arrPropName(1)), Integer)
intMult = CType(frmNewProject.weightSettings.Items.Item(arrPropName(0) + "_" + arrPropName(2)), Integer)
cuScores(i) = intScore * intMult
End If
Else
cuScores(i) = 0
End If
i += 1
Next
For Each txt In pan.ChildControls(Of TextBox)
txt.Text = cuScores.Max.ToString
Next
intPgScore += cuScores.Max
End If
Next
End If
For Each chk As CheckBox In tab.ChildControls(Of CheckBox)
intScore = 0
arrPropName = Split(chk.Name.Replace("chk", ""), "_")
If Not arrPropName(0) = "CU" Then
If chk.Checked Then strYesNo = "_Yes" Else strYesNo = "_No"
strPropName = arrPropName(0) + "_" + arrPropName(1) + strYesNo
Dim w = dbTPT.tbl_Weights.FirstOrDefault(Function(n) n.Weight_Name = strPropName)
If w IsNot Nothing Then
intScore = CType(frmNewProject.weightSettings.Items.Item(strPropName), Integer)
End If
End If
intPgScore += intScore
Next
For Each rad As RadioButton In tab.ChildControls(Of RadioButton)
intScore = 0
arrPropName = Split(rad.Name.Replace("rad", ""), "_", 2)
strPropName = arrPropName(0) + "_" + arrPropName(1)
If rad.Checked Then
Dim w = dbTPT.tbl_Weights.FirstOrDefault(Function(n) n.Weight_Name = strPropName)
If w IsNot Nothing Then
intScore = CType(frmNewProject.weightSettings.Items.Item(arrPropName(0) + "_" + arrPropName(1)), Integer)
End If
End If
intPgScore += intScore
Next
For Each cbox As ComboBox In tab.ChildControls(Of ComboBox)
intScore = 0
If cbox.SelectedIndex > -1 Then
If cbox.SelectedIndex = 0 Then
intScore = 0
Else
strPropName = cbox.Name.Replace("cbox", "") + cbox.SelectedValue
Dim w = dbTPT.tbl_Weights.FirstOrDefault(Function(n) n.Weight_Name = strPropName)
If w IsNot Nothing Then
intScore = CType(frmNewProject.weightSettings.Items.Item(strPropName), Integer)
End If
End If
intPgScore += intScore
End If
Next
End Using
Return intPgScore
End Function
End Module
6) Selected tab is painted
Private Sub Paint_Tab(sender As Object, e As PaintEventArgs) Handles _
pgAcademic.Paint, pgBusiness.Paint, pgLIS.Paint, pgPatient.Paint, pgRegulatory.Paint
tabDetails.ResumeLayout()
pgAcademic.ResumeLayout()
pgBusiness.ResumeLayout()
pgLIS.ResumeLayout()
pgPatient.ResumeLayout()
pgRegulatory.ResumeLayout()
End Sub