[RESOLVED] [2005] Me.visible = false not working on form load

[mightor]

Hi there,

I am very new to VB.net but not programming per se. However, something has me stumped and I have been as yet unable to find a solution.
I created a very simple form that when loaded should not be visible but have a little systray icon only. The systray icon part works, however the form is not being hidden. This is the code (all of it) that *should* work:

Public Class Form1
    Private Sub NotifyIcon1_MouseDoubleClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles NotifyIcon1.MouseDoubleClick
        MsgBox("You clicked on the notification icon")
        Me.Visible = True
    End Sub

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Me.Visible = False
        NotifyIcon1.Visible = True
    End Sub
End Class

So why is this not working? Am I missing something here? I took the Me.Visble = False trick from a piece of code I found on the web (link)

If someone could point me in the right direction that would be great!

Thanks in advance.
Mighor

[stanav]

Use the Form Shown event of the form instead

Private Sub Form1_Shown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shown
        Me.Visible = False
        NotifyIcon1.Visible = True
    End Sub

[mightor]

I tried the above code but what happens now is that the form shows for a millisecond and then disappears quickly. What I basically want is the form to not show at all when it is first started up.
I need to make it invisible before it is show, if you know what I mean

[Half]

Put 'Me.WindowState = FormWindowState.Minimized' in the form_load event. If you also don't want it in the taskbar, use Me.ShowInTaskbar = False.

[mightor]

Thanks, that did the trick!
I now have the following code and it seems to do exactly what I need it to do:

Public Class Form1
    Private Sub NotifyIcon1_MouseDoubleClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles NotifyIcon1.MouseDoubleClick
        MsgBox("You clicked on the notification icon")
        Me.Visible = True
        Me.ShowInTaskbar = True
        Me.WindowState = FormWindowState.Normal
    End Sub

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Me.Visible = False
        Me.ShowInTaskbar = False
        Me.WindowState = FormWindowState.Minimized
    End Sub

    Private Sub Form1_Shown(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Shown
        Me.Visible = False
        NotifyIcon1.Visible = True
    End Sub
End Class

[VBDT]

Don't forget to make your project as a Single Instance application, other wise you will see minimized main form instances. Also you don't need to set the Visible property if you use ShowInTaskbar property.

[mightor]

Don't forget to make your project as a Single Instance application, other wise you will see minimized main form instances.

My application will only have one single window (form). Is this what you meant by Single Instance application?

[VBDT]

I mean single instance application. For example when you start your app by clicking the app shortcut icon on your desktop and after it opens you click the shortcut the secont time it will start your app but a diferent instance so you will see two of your forms.

[mightor]

I mean single instance application. For example when you start your app by clicking the app shortcut icon on your desktop and after it opens you click the shortcut the secont time it will start your app but a diferent instance so you will see two of your forms.

I see what you mean now. I am not sure how to achieve this. How is this done under Windows and more specifically in Visual Basic? There should indeed be no more than one instance of this application.

[VBDT]

Go to your project properties and check the checkbox for "Make Single Instance Application".

[mightor]

Go to your project properties and check the checkbox for "Make Single Instance Application".

Haha, ok that was a lot easier than I thought it would be I was already googling for some example code to achieve this and I came across a lot of talk about mutexes and other IPC stuff. I am glad a tickbox is all that is required.

[Half]

One thing in case you decide to expand your project later on - there is some unexpected behaviour when a form is not shown in the taskbar. For example such a form won't fire the FormClosing event last time I checked.

If you notice strange things happening, first test your thing with ShowInTaskbar set to true.

[VBDT]

One thing in case you decide to expand your project later on - there is some unexpected behaviour when a form is not shown in the taskbar. For example such a form won't fire the FormClosing event last time I checked.

If you notice strange things happening, first test your thing with ShowInTaskbar set to true.

Yes that is true. It all depends how you exit the application. If you use Application.Exit than it will not fire the FormClosing event, instead use Me.Close.

[mightor]

Yes that is true. It all depends how you exit the application. If you use Application.Exit than it will not fire the FormClosing event, instead use Me.Close.

Thanks, I will keep that in mind as I expand on this project.

[jmcilhinney]

Also you don't need to set the Visible property if you use ShowInTaskbar property.

Not true. If you have a minimised form that is not in shown in the task bar it will still appear in the Alt+Tab list. Selecting the form using Alt+Tab will restore it. Not what you want.

What you should do is get rid of the entire Form.Load event handler. You should be setting the WindowState and ShowInTaskbar properties of the form and the Visible property of the NotifyIcon in the designer. All that's left to do then is set the Visible property of the form to False in the Shown event handler.

[jmcilhinney]

Yes that is true. It all depends how you exit the application. If you use Application.Exit than it will not fire the FormClosing event, instead use Me.Close.

Also, not true I'm afraid. Application.Exit does not raise the Closing and Closed events but it does raise the FormClosing and FormClosed events. FormClosing provides the e.CloseReason property so you know how the closure was instigated in the first place. ApplicationExitCall is one of those reasons.

[VBDT]

Not true. If you have a minimised form that is not in shown in the task bar it will still appear in the Alt+Tab list. Selecting the form using Alt+Tab will restore it. Not what you want.

What you should do is get rid of the entire Form.Load event handler. You should be setting the WindowState and ShowInTaskbar properties of the form and the Visible property of the NotifyIcon in the designer. All that's left to do then is set the Visible property of the form to False in the Shown event handler.

I just tested it and you are right! I didn't notice that.

[VBDT]

Also, not true I'm afraid. Application.Exit does not raise the Closing and Closed events but it does raise the FormClosing and FormClosed events. FormClosing provides the e.CloseReason property so you know how the closure was instigated in the first place. ApplicationExitCall is one of those reasons.

It is true if the app's main window has its ShowInTaskbar property set to true but if the property is set to false and we call Application.Exit method then for some reason the FormClosing and FomClosed events doesn't fire.

[jmcilhinney]

It is true if the app's main window has its ShowInTaskbar property set to true but if the property is set to false and we call Application.Exit method then for some reason the FormClosing and FomClosed events doesn't fire.

That I didn't know. One all.

[mightor]

I am not sure how to do this but as far as I am concerned this thread can be marked as [RESOLVED]. Thanks for all the insights, tips and tricks, people!