VB.NET: Problem with Multiple Forms

Question

Good day guys! I have a question in VB.NET. While creating and testing my GUI for a login screen to show up the main page of the payroll system, there's this problem.

The splash screen loads normally, and the login form appear. I type my username and password (e.g. Username: Admin, Password: 12345) and login was successful. Here's the problem: When the Main Menu shows up, the Login screen appears AGAIN, which is at this time, that screen should be already closed. Did I have any problem with the use of Show, Hide, and Close?

Here's my code for the three forms.

A. Splash Screen

Public Class frmSplashScreen

Private Sub tmrSplashScreen_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrSplashScreen.Tick
    Me.Hide()
    frmLogin.Focus()
    frmLogin.Show()
End Sub

End Class

B. Login Form (for system access)

Public Class frmLogin

Public userName As String
Public passWord As String

Private Sub cmdExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdExit.Click

    End

End Sub

Private Sub cmdSubmit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdSubmit.Click

    userName = txtUsername.Text
    passWord = txtPassword.Text

    If userName = "Admin" And passWord = "12345" Then
        MsgBox("Access Granted! Welcome to BYTE!", MsgBoxStyle.Information, "Byte EGC Payroll System")
        Me.Close()
        frmMainMenu.Show()
        frmMainMenu.Focus()
    Else
        MsgBox("Access Denied!", MsgBoxStyle.Critical, "Byte EGC Payroll System")
    End If

End Sub

End Class

and lastly:

C. Main Menu.

Public Class frmMainMenu

Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click

    End

End Sub

Private Sub frmMainMenu_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    Me.WindowState = FormWindowState.Maximized

End Sub

Private Sub AboutToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AboutToolStripMenuItem.Click

    MsgBox("Byte" & vbCrLf & "By: JU-CHAN", vbInformation, "Byte Payroll System")

End Sub

End Class

Help is greatly appreciated. Thank you! :)

Answer 1

The timer keeps ticking, causing the splash screen to reload, then hide, showing the login screen again.

Try putting this in the tmrSplashScreen tick handler:

tmrSplashScreen.Enabled = False

Answer 2

Your splash screen shouldn't be controlling when the logon form shows. A splash screen should only be used during the startup of the program when it's doing a lot of processing in the background before the program can actually start up. Just showing a splash screen for the sake of doing it will annoy end users.

Since your basic logon screen above doesn't look like it would take a lot of resources to use, a better option would be to use the flow of:

Show Logon screen
If password is successful then
- display splash screen
- load application in the background
- once application is loaded, display main window and hide splash scrfeen

Some sample code for this would be:

Module modMain
    'In a module 
    Public frmSpl As frmSplash
    Public frmMain As frmMainMenu

    Public Sub Main(ByVal args() as String)
        dim frmLogin as New frmLogin

        'Assume frmLogin is a modal form
        frmLogin.Show

        'A public property set on the Login form
        If frmLogin.Passed = True Then Do
            'Load and display the splash screen
            frmSpl = New frmSplash
            frmSpl.Cursor = Cursors.WaitCursor
            frmSpl.Show()
            Application.DoEvents()

            'If there is any code needed to run before displaying the Main Form
            'do it here 

            frmMain = New frmMainMenu

            'Begin running standard application loop for frmMainMenu
            Application.Run(frmMain)
        End If
    End Sub
End Module

Then in frmMainMenu you would have code similar to:

Public Class frmMainMenu

    Private Sub frmMainMenu_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Try
            Me.Cursor = Cursors.WaitCursor
            Me.SuspendLayout

            Me.WindowState = FormWindowState.Maximized

            'Put any other loading code needed for this form here
        Catch (ex as Exception)
            'Handle exceptions here
        Finally
            'Hide the splash screen
            frmSpl.Hide()
            frmSpl.Dispose()

            'Display the form
            Me.ResumeLayout
            Me.Cursor = Cursors.Default
            Me.Show
        End Try

    End Sub

Answer 3

I'm betting your problem is that the timer in your splash screen is still firing _tick events and bringing up the login page again.

Maybe add tmrSplashScreen.Stop() before you hide the splash screen?

Or better yet. Get rid of the splash screen altogether, they are evil.