Switching between forms (VB.NET)

I always get an exception when I try to switch between different forms in my program. Maybe you will help me to solve this issue. Here is the exception message:

Control.Invoke must be used to interact with controls created on a separate thread

I have attached the forms to very nice variables and this problem occurs when I try to use command like MyForm.Show().

It does not happen when the forms are not attached to variables, but then I have collosal problems with refreshing the textboxes and stuff.

Hope to开发者_C百科 hear you soon!

edit;

I have 4 different forms. When I load the main module and main form, in the Sub (...) Handles MyBase.Load I execute the following code:

In module:

Public StartupForm As frmStartup
Public RegularForm As frmRegularUse
Public LoginForm As frmLogin
Public PasswordForm As frmPassword
Public SettingsForm As frmSettings

In main form:

RegularForm = Me
StartupForm = frmStartup
LoginForm = frmLogin
PasswordForm = frmPassword
SettingsForm = frmSettings

This is the aproach I worked out to get the full control over refreshing the forms. It is a program for Motorola Scanner with Windows CE. Now, for example, when I enter the correct password in LoginForm, I want to switch to the RegularForm. When I try to use RegularForm.Show() or RegularForm.ShowDialog or RegularForm.BringToFront(), I get an exception. When I try to call the form with the frmRegularUse.Show() I can call the form, but it is being created in a different thread, I believe, so I loose control over it (when I try to put something from the keyboard, there is no response).

I doubt the forms are getting created in a different thread, but if they are then STOP, go back, and fix that. All of your forms should be created and accessed from the main GUI thread. Secondly, I don't think you "newed" the forms. You need something like this:

StartupForm = New frmStartup 
RegularForm = New frmRegularUse 
LoginForm = New frmLogin 
PasswordForm = New frmPassword 
SettingsForm = New frmSettings 

Actually, what I did is:
Still I have the same code in the main module, which is:

Public StartupForm As frmStartup
Public RegularForm As frmRegularUse
Public LoginForm As frmLogin
Public PasswordForm As frmPassword
Public SettingsForm As frmSettings

I managed it to work in the simpliest possible way. For example - I run the Login form, and execute the following code (long story short):

LoginForm = Me
frmRegularUse.ShowDialog()

I jump to the frmRegularUse form, where, once again, I execute:

RegularForm = Me
frmPasswordForm.ShowDialog()

And so on...
I made some tests and it works quite okay. Tomorrow I will try to make it a little bit more sophisticated. ;-)