Trouble switching between projects/forms in vb.net - vb.net

I am working on a project in Visual Studio Community 2019 using VB.Net. I am developing a user interface wherein users start on one form (a sort of index, call it form 1) and select from their the next form they want to go to (say form 2). This part is working fine. The trouble is that after users finish in form 2, they should be directed back to form 1 to continue from here, and I can't get this to happen. I need somehow to make the main menu a public shared form so that the other projects can access it but I can’t figure out how to do that.
Here are the relevant lines from form 1:
Public Class frmMainMenu
Public Shared inst As frmMainMenu
Private Sub frmMenu_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
inst = Me
Timer1.Start()
Me.Show()
End Sub
Private Sub BtnGeology_Click(sender As Object, e As EventArgs) Handles
btnGeology.Click
Dim formNew As New Geology.frmGeologyMenu
formNew.Show()
Timer1.Stop()
Me.Hide()
End Sub
And here are the relevant lines from form 2. I want lines 23 and 24 to return the user to the main menu, but it doesn't work.
Public Class frmGeologyMenu
Public Sub frmGeologyMenu_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
lblTime.Text = 10
Me.Show
End Sub
Private Sub BtnMainMenu_Click(sender As Object, e As EventArgs) Handles
btnMainMenu.Click
inst.frmMainMenu.Show()
inst.frmMainMenu.Timer1.Start()
Me.Close()
End Sub
I appreciate any help you can offer!

From my comments above:
When you create your instance of your second form called "formNew",
use the AddHandler command to wire up its FormClosed event to a method
in the main form. Then in the second form you can just call Me.Close()
and the method in the main form will fire where you can call
Me.Show()..
In main menu:
Public Class frmMainMenu
Private Sub BtnGeology_Click(sender As Object, e As EventArgs) Handles btnGeology.Click
Dim formNew As New Geology.frmGeologyMenu
AddHandler formNew.FormClosed, AddressOf formNew_FormClosed
Timer1.Stop()
Me.Hide()
formNew.Show()
End Sub
Private Sub formNew_FormClosed(sender As Object, e As FormClosedEventArgs)
Me.Show()
Timer1.Start()
End Sub
End Class
In frmGeologyMenu:
Public Class frmGeologyMenu
Public Sub frmGeologyMenu_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
lblTime.Text = 10
End Sub
Private Sub BtnMainMenu_Click(sender As Object, e As EventArgs) Handles btnMainMenu.Click
Me.Close()
End Sub
End Class

In VB.NET, your startup form is always the default instance of its type. That means that you can simply use the type name to refer to your startup form anywhere in your app. If you use Me.Hide() in your startup form then frmMainMenu.Show() can be used anywhere to redisplay it. This would not be the case in C# as default form instances are a VB-specific feature. See here for more info.

Related

Switching forms in vb.net

I am a volunteer for the National Park Service trying to convert an interactive display originally created 20 years ago in a language called ToolBook into Visual Basic. The program consists of several projects under a single solution. The starting project, called "MainMenu", can be thought of as a library, with buttons that bring up “books.” The project called Geology is an example “book” and GeologyMenu can be thought of as the index of a book. The buttons on GeologyMenu connect to “chapters” that explain and show examples of geologic processes in the park. The “chapters” are within the project “Geology” and work fine within the project. All forms used in the program have timers that allow the program to re-set itself to MainMenu when not in use.
In a previous post, with the help of Idle Mind (thank you again), the following code for works fine for going from MainMenu to GeologyMenu and in the reverse direction as long as no button is pushed on GeologyMenu. However, if I go to a “chapter” I can no longer get back to the MainMenu from the GeologyMenu. Here is the relevant code:
MainMenu
Public Class frmMainMenu
Private Sub BtnGeology_Click(sender As Object, e As EventArgs) Handles btnGeology.Click
Dim formNew As New Geology.frmGeologyMenu
AddHandler formNew.FormClosed, AddressOf formNew_FormClosed
TimerMain.Stop()
formNew.Show()
Me.Hide()
End Sub
Private Sub formNew_FormClosed(Sender As Object, e As FormClosedEventArgs)
lblTime.Text = 8
TimerMain.Start()
Me.Show()
End Sub
GeologyMenu
Public Class frmGeologyMenu
Public Sub frmGeologyMenu_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
lblTime.Text = 6
TimerGeologyMenu.Enabled = True
Me.Show()
End Sub
Private Sub BtnErosion_Click(sender As Object, e As EventArgs) Handles btnErosion.Click
TimerGeologyMenu.Stop()
frmErosionP01.Show()
Me.Hide()
End Sub
The code below for takes the viewer to the Erosion “chapter”
Private Sub BtnErosion_Click(sender As Object, e As EventArgs) Handles btnErosion.Click
TimerGeologyMenu.Stop()
frmErosionP01.Show()
Me.Hide()
End Sub
Erosion “Chapter” . This is the code for the button on every form in Erosion that takes the program back to GeologyMenu
Public Class frmErosionP02
Private Sub BtnGeologyMenu_Click(sender As Object, e As EventArgs) Handles btnGeologyMenu.Click
My.Computer.Audio.Stop()
frmGeologyMenu.lblTime.Text = 10
frmGeologyMenu.TimerGeologyMenu.Enabled = True
frmGeologyMenu.Show()
Me.Close()
End Sub
The code for forms within Erosion takes me back to GeologyMenu, but then MainMenu won’t show when I close GeologyMenu and I don’t understand why or how to fix it. Thank you in advance for your help!
Simply, pass the previous menu/Form to the new one in a parameterized constructor and keep it in a class variable, then handle the Form.Closed event of the new menu to show the previous one.
Example for the relevant code:
Public Class frmMainMenu
Inherits Form
Private Sub BtnGeology_Click(sender As Object, e As EventArgs) Handles btnGeology.Click
Dim formNew As New frmGeologyMenu(Me)
Me.Hide()
formNew.Show()
End Sub
End Class
Public Class frmGeologyMenu
Inherits Form
Private PreviousMenu As Form
Private Sub New()
InitializeComponent()
'...
End Sub
Sub New(prevMenu As Form)
Me.New()
PreviousMenu = prevMenu
AddHandler FormClosed,
Sub(s, e)
PreviousMenu.Show()
End Sub
End Sub
Private Sub BtnErosion_Click(sender As Object, e As EventArgs) Handles btnErosion.Click
Dim frmErosion As New frmErosionP02(Me)
Me.Hide()
frmErosion.Show()
End Sub
End Class
Public Class frmErosionP02
Inherits Form
Private PreviousMenu As Form
Private Sub New()
InitializeComponent()
'...
End Sub
Public Sub New(prevMenu As Form)
Me.New()
PreviousMenu = prevMenu
AddHandler FormClosed,
Sub(s, e)
PreviousMenu.Show()
End Sub
End Sub
End Class

Best way to use a form as a GUI, but code it elsewhere

I'm wanting to use visual studio to create a form with buttons, but then have it coded elsewhere, so that I can use the events (ie; button clicks) to perform specific actions in this application.
Is it possible/practical to do this? If not/if so, what do I need to look up and learn about from here to be able to implement it? My knowledge base in programming is limitted; I've just been starting to get familiar with Classes.
(I'm working in Autodesk Inventor, and am trying to create a prompt window with buttons to control the output of another program I have. In order to save on the amount of calls/interfacing, I was hoping to just create an uncoded button form, but code it within my program/macro I have within Inventor - its to be a form with six buttons that end up rotating some graphics within the program at a certain stop point, and then the program resumes when the form is closed via the "x")
I have seen posts such as the one below, but that doesn't seem to have the capability to receive user input: How to create a custom MessageBox?
Currently I am here, which works for showing the toolbox. Can someone show me how I would handle the events please?
AddReference "C:\Users\Documents\Visual Studio 2013\Projects\WindowsApplication1\WindowsApplication1\bin\Release\SectionSymToolBox.dll"
Imports System.Windows.Forms
Public Class SectionSymRule
'Public dlg As New System.Windows.Forms.For
Public Shared ToolBox As New SectionSymToolBox.SectionSymToolBox
Dim WithEvents EClass As New EventClass
Sub Main()
ToolBox.Show()
End Sub
End Class
Public Class SectionSymToolBox
Private Sub Main()
End Sub
Public Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
'Swap Symbols
End Sub
Public Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'Flip Symbol
End Sub
Public Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
'Flip Text
End Sub
Public Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
'<
End Sub
Public Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
'>
End Sub
End Class
You can always use Partial Class to split your code into multiple files.
So you create your Form (say Form1) the normal way. Then put the code in another class file with class declared as Partial
For example,
Partial Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox(TextBox1.Text)
End Sub
End Class
The other way is to inherit your Form. The inherited form will then have everything of whatever is on the form, with whatever you want to add.
Public Class Form1Code
Inherits Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox(TextBox1.Text)
End Sub
End Class

Reset My.Settings to values last saved

I'm currently using a "Settings" form to set various settings for my application. What I'm trying to do is to revert settings back to before any changes the user has made before opening and changing a field. I have a text box with a data binding to a setting and when I make a change and click okay it gets saved the next time I open it. When I hit cancel it also gets saved. Not quite sure if I'm approaching this correctly.
Public Class frmSettings
Private _mysettings As Configuration.SettingsBase
Private Sub frmSettings_Load(...) Handles Me.Load
_mysettings = My.Settings
End Sub
Private Sub btnCancel_Click(...) Handles btnCancel.Click
For Each p As Configuration.SettingsPropertyValue In _mysettings.PropertyValues
My.Settings(p.Name) = p.PropertyValue
Next
Me.Close()
End Sub
Private Sub btnOkay_Click(...) Handles btnOkay.Click
My.Settings.Save()
Me.Close()
End Sub
End Class
Rather than using databound control you can simply load the value of the setting when the settings form loads. It is simple doing it that way, and it works. Otherwise you would have to make a clone of My.Settings: doing _mysettings = My.Settings is only creating a pointer to My.Settings, not a copy of it.
For example, I have a Form named ChangeConnectionString which has OK/Cancel buttons and a TextBox control named connString:
Public Class ChangeConnectionString
Private Sub bnOK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnOK.Click
My.Settings.connectionString = connString.Text
My.Settings.Save()
Me.Close()
End Sub
Private Sub bnCancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bnCancel.Click
Me.Close()
End Sub
Private Sub ChangeConnectionString_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
connString.Text = My.Settings.connectionString
End Sub
End Class

form starting but not displaying vb.net

So I was coding a program that opens 20 web browsers on one page, for a youtube or view bot any URL really, but when I launched the program It displayed the text box I put in to see if it was actually starting and then nothing else
So my question is, Whats wrong with my code?
startup form (where you can launch the main code with button 1)
Public Class Startup
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Settings.Show()
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
views.Show()
End Sub
End Class
main form
Public Class views
Private Sub views_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
MessageBox.Show("Form Initalised")
WebBrowser1.Navigate(My.Settings.url)
WebBrowser2.Navigate(My.Settings.url)
WebBrowser3.Navigate(My.Settings.url)
WebBrowser4.Navigate(My.Settings.url)
WebBrowser5.Navigate(My.Settings.url)
WebBrowser6.Navigate(My.Settings.url)
WebBrowser7.Navigate(My.Settings.url)
WebBrowser8.Navigate(My.Settings.url)
WebBrowser9.Navigate(My.Settings.url)
WebBrowser10.Navigate(My.Settings.url)
WebBrowser11.Navigate(My.Settings.url)
WebBrowser12.Navigate(My.Settings.url)
WebBrowser13.Navigate(My.Settings.url)
WebBrowser14.Navigate(My.Settings.url)
WebBrowser15.Navigate(My.Settings.url)
WebBrowser16.Navigate(My.Settings.url)
WebBrowser17.Navigate(My.Settings.url)
WebBrowser18.Navigate(My.Settings.url)
WebBrowser19.Navigate(My.Settings.url)
WebBrowser20.Navigate(My.Settings.url)
Threading.Thread.Sleep(My.Settings.Time)
reload.Show()
Me.Close()
End Sub
End Class
and form reload mentioned in the main form.
Public Class reload
Private Sub reload_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Me.Close()
views.Show()
End Sub
End Class
Try to use the Form.Shown event instead of the Form.Load event. In Form.Load the controls are often not fully initialized and if something goes wrong there the initialization of the whole form sometimes goes awry. It's better to use the Form.Shown for such lengthy procedures you have there.

Reacting to third-party application form events using vb.net

I would like to know how I should code my VB.net application to react to the form load event in a third-party application (also written in VB.net)
To test, I have created two basic programs, one with two forms (program A) and one (program B) that attempts to the listen to program A's appropriate form load event. I have tried using WithEvents but it does not get fired when Program's A second form loads.
Here is the code for Program A:
Public Class StartPage
Public WithEvents loadtimer As New System.Windows.Forms.Timer
Private Sub StartPage_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
loadtimer.Interval = 1000
loadtimer.Enabled = True
loadtimer.Start()
End Sub
Private Sub loadtimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles loadtimer.Tick
loadtimer.Stop()
SystemStatus.Show()
End Sub
End Class
Public Class SystemStatus
Inherits StartPage
Private Sub StartPage_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Me.Label1.Text = "This is the form that I want to listen for the load event"
Me.loadtimer.Enabled = False
End Sub
End Class
Here is the code for Program B:
Imports Program_A
Public Class ListeningForm
Dim WithEvents testlisten As New Program_A.SystemStatus
Private Sub testlisten_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles testlisten.Load
Label1.Text = "SystemStatus form loaded"
End Sub
Private Sub ListeningForm_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Label1.Text = "Waiting for SystemStatus load event..."
End Sub
End Class
I am quite new when it comes to programming so maybe this is not even possible or I just haven't been understanding what I've been reading. In any case please enlighten me as to what my next course of action should be.
Thanks very much in advance,
theoleric
This will do what your asking.
Imports Program_A
Public Class ListeningForm
Dim WithEvents testlisten As New SystemStatus
Private Sub testlisten_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles testlisten.Load
' now this event will fire
Label1.Text = "SystemStatus form loaded"
End Sub
Private Sub ListeningForm_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Label1.Text = "Waiting for SystemStatus load event..."
' the load event will not fire until you call this
testlisten.Show()
End Sub
End Class