Is there any way to do the following, other than hiding then closing the hidden form later?
Mainform opens SecondForm as show dialog, i need to Open ThirdForm from SecondForm while closing SecondForm while keeping third form acting as "showdialog" on the MainForm?
When you show SecondForm(), pass in MainForm() as the owner to ShowDialog():
Public Class MainForm
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim sf As New SecondForm
If sf.ShowDialog(Me) = Windows.Forms.DialogResult.OK Then
' ... do some processing in here ...
End If
End Sub
End Class
Now, in SecondForm(), you can then set the owner of ThirdForm() to that of SecondForm():
Public Class SecondForm
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Me.Hide()
Dim tf As New ThirdForm
tf.ShowDialog(Me.Owner)
Me.DialogResult = Windows.Forms.DialogResult.OK
End Sub
End Class
You could simply open the third form from the main form as soon as the second form returns a dialog result
You also might want to look at MDI this gives you more control over what the user can and can't do.
After trying Idle_mind suggestion it was still giving me problems going back and forth between forms continously showing them as .showdialog. I solved my problem just like tinstaafl suggested. I wish i would have got his message before a couple hours of trying different methods before coming up with this one.
When i close each form, i set a boolean flag in the main form. then i call a sub that is in the main form to show the next form as showdialog from the main form. i use the flag which triggers logic in the form im loading whether or not to bind data from datatable so i can edit it.
sorry with all those forms i know it gets confusing. to sum it up, close the dialog form (me.close), set flag so calling code knows what to do once the showdialog code is satisfied.
Related
Currently in my windows form, I have a few WinForms to work with. One WinForm acts as a main menu and is supposed to call another form as a secondary window on its own.
Private Sub btnMainGame_Click(sender As Object, e As EventArgs) Handles btnMainGame.Click
' This is the button to call up the main game controller. So simply hide this form aned then open the new form.
Dim frmController As New frmControllerScreen
frmController.Show()
Me.Hide() ' Happens on .Close as well
End Sub
The above code invokes another WinForm which is used to handle more options. When the user clicks on a particular button, a sub form is created again.
Dim OpenNewGameWindow As New frmGameConfig
OpenNewGameWindow.ShowDialog(Me)
Me.DialogResult = DialogResult.None ' Used to prevent the subform from closing the main form when it catches a dialog result.
Now in the frmGameConfig, the program is supposed to take data and pass it back to the form that called it.
Private Sub btnNewGameStartGame_Click(sender As Object, e As EventArgs) Handles btnNewGameStartGame.Click
' ... Skipped code...
frmControllerScreen.MasterQuestionList = QuestionList
frmControllerScreen.blnBankedTime = cbBankedTime.Checked
' ... Skipped code...
End Sub
However, when the frmController tries to reference MasterQuestionList... it returns a nullreference error as if it was not set.
Here's where things get funny...
When I made this code, frmControllerScreen was actually the startup form. Now when I change this form back to frmMainMenu, I get NullReference errors constantly.
My question: How am I supposed to pass information from one form to the next form if it was instantiated from a parent form. (Note I even moved the declartion to Public as a "module-wide" variable... and nothing happens but the same result.) The same error happens even if I go ahead and declare frmController.MasterQuestionList as well.
Instead of trying to pass data back from the called form to the caller, you can reference the called form's controls from the calling code after .ShowDialog.
Dim OpenNewGameWindow As New frmGameConfig
If OpenNewGameWindow.ShowDialog() Then
MasterQuestionList = OpenNewGameWindow.QuestionList
blnBankedTime = OpenNewGameWindow.cbBankedTime.Checked
End If
In OpenGameWindow button click:
Private Sub btnNewGameStartGame_Click(sender As Object, e As EventArgs) Handles btnNewGameStartGame.Click
Me.DialogResult = True
End Sub
I am trying to create a customized form class (CustomBorderlessForm) in VB.NET.
My Progress So Far
I created a new Class and named it CustomBorderlessForm.vb
I then proceeded to write the following code:
CustomBorderlessForm.vb
Public Class CustomBorderlessForm
Inherits Form
Dim _form As Form = Nothing
Public Sub New(form As Form)
_form = form
MsgBox("Testing: New()")
End Sub
Protected Overrides Sub OnMouseMove(e As MouseEventArgs)
MyBase.OnMouseMove(e)
MsgBox("Testing OnMouseMove()")
End Sub
End Class
Form1.vb
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim form As New CustomBorderlessForm(Me)
End Sub
End Class
Results of progress
A message box displays "Testing: New()" on load
Nothing shows on mouse move
As you can see, my problem lies with the events
Questions
Is it possible to create a form object and use that instead of the pre-populating form?
If so, can I give this form custom properties, such as, a border and some boolean values (shadow...etc), just like any other custom object/class?
What am I doing wrong in my current approach?
Why isn't the OnMouseMove being overridden?
Am I initialising the class wrong?
Can it even be done this way?
After creating a form you also need to show it. Change your logic to:
Dim form As New CustomBorderlessForm(Me)
form.Show()
Before you do that, I'd recommend changing from MsgBox to Console.WriteLine(), otherwise you can run into a fun/frustrating little cat and mouse game.
EDIT
Based on the comments, if, from VS you did a "Add New, Windows Form" you can just right-click the project, select property and on the Application tab change the Startup object to your new form. VS only allows you to do this with forms it creates for you (by default, more on this later).
If you wrote that file by hand (which is absolutely fine) you can perform the Show() like I did above and call Me.Hide() to hide the "parent" form. Unfortunately the Load event is fired before the Show event so if you place this in Form1_Load() it won't work. Instead you can use the Shown event like this:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim form As New CustomBorderlessForm(Me)
form.Show()
End Sub
Private Sub Form1_Shown(sender As Object, e As EventArgs) Handles Me.Shown
Me.Hide()
End Sub
Another option has to do with "Application framework". You can read about it here however it basically handles application events that other languages have to manually implement. If you go into your project properties you can uncheck the "Enable application framework" checkbox. This will give you more option in the "Startup object" dropdown. If you add the following code to your project one of the items in the Startup object dropdown menu should now be "Loader"
Public Module Loader
<STAThread()>
Public Sub Main()
Dim form As New CustomBorderlessForm(Nothing)
form.ShowDialog()
End Sub
End Module
You'll notice that the above bypasses Form1 completely. Also, instead of Show() I'm using ShowDialog() because otherwise the form shows and then the program ends.
I encounter the following scenarios when I try to use 2 forms. My workflow is as follows:
(1) Load Form1.
(2) A click on button1 on Form1 closes Form1 and opens Form2.
Solution A: If I use the following code:
Dim oForm As New Form2
oForm.ShowDialog()
Me.Close()
Then Form1 will be under Form2 (Form1 still opens).
Solution B: If I use the following code:
Dim oForm As New Form2
oForm.Show()
Me.Close()
Then Form1 closes and Form2 opens, but Form1 is not on the top layer.
I have looked through the solutions for this, most propose solution B, but for me, both solutions won't work the way I want. Can anybody tell me the reason?
Try
Dim oForm as New Form2
oForm.Show()
and on Load event of form2
Form1.Hide()
Use form.bringtofront() if you want to see the opening Form in the front, I m little confused though about what you are trying to do
Try doing it this way:
Dim oForm As New Form2()
Me.Hide()
oForm.ShowDialog()
Me.Close()
I suspect your are building a log-in dialogue... if so, or something similar, try this..
Open your main form first... (Form 2), have form2 showdialog (modally) form1... this will put form1 on top of form2.
Add a property to form 1, that gets set depending on what happens there.. sucessfull login for instance.
Close form 1 from its own methods... (after successful authentication), set the property before closing.
On form2, read this property of form1, and then dispose form1, and decide what to do... if unsuccessful login, show the login form again, end app. If successful, just gracefully exit out of the method that showed form1. Your form 2 is now the only form open.
Start with Form2
Form2_load
dim f1 as new form1
f1.showdialog
if f1.someproperty = somevalue then
' do something here, for instance, pop the form again, if you did not get what you were lookign for...
end if
'gracefully let the function end and form2 is now the only open form..
'dispose of form1. form1's close call does not dispose it, because it was opened modally. (showdialog)
f1.dispose
f1 = nothing
in form1, depending on what you are doing, set the custom property and call me.close, this will exit the form, and run the next code in form2.
try this:
Dim oForm As New Form2
oForm.Show()
Me.Visible = False
You would to close your first form and this close your program. If you set him on invisible, he is not closed.
Just go to form2 and write the Form1.hide() . I tried to close form1 but it closed my whole program.
Public Class Form2
Private Sub Form2_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Form1.Hide()
End Sub
End Class
how do i close my form after opening the next form (VB.net Windows form) like the Next button
I tried Form2.show() it shows form2 but does not close the form1 and if i type me.close(), the entire project stops
If you just want Form2 to be Visible you can hide Form1 when you show Form2, then show it Form1 again when you close Form2. What is happening is that once you close Form1 your program will exit see below edit.
Something like this.
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim frm2 As New Form2
AddHandler frm2.FormClosed, AddressOf Form2Closing
frm2.Show()
Me.Hide()
End Sub
Private Sub Form2Closing(sender As Object, e As FormClosedEventArgs)
Me.Show()
RemoveHandler DirectCast(sender, Form2).FormClosed, AddressOf Form2Closing
End Sub
If you just are wanting to Close Form1 and not go back to it once Form2 is open, you can change your project settings from When startup form closes(which is the default) to When last form closes then you can close your first form without closing your application.
You have to specify what to close:
Form1.Close()
You better not close your form after opening another one from it, unless you want that other one also closed. Otherwise it will cause ownership and visibility side effects, which you really don't want to deal with in the long run.
This is exactly why me.close() on your main form stops your project. You just have consider paradigms Microsoft put into a Winforms application. If you don't, you are guaranteed to get in trouble.
Instead, a wizard control is what you are probably looking for.
VB2010. I must be missing something because I couldn't find a solution after searching for an hour. What I want to do is simple. In my app I want to display a modeless form so that it is floating while the user can still interact with the main form.
dim f as New frmColors
f.Show(Me)
But I only want one instance of the form at any time. So how can I prevent more than once instance being displayed, and if there is one instance then just give it focus?
Does something like this work for you, if the form is already visible you can not do a Show, you can just do a BringToFront, also you can check to see if the Form has been disposed so you can New up another one.
Public Class Form1
Dim f As New frmColors
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
If f.IsDisposed Then f = New frmColors 'To handle user closing form
CheckForm(f)
End Sub
Private Sub CheckForm(frm As Form)
If frm.Visible Then
frm.BringToFront()
Else
frm.Show(Me)
End If
End Sub
End Class
Make your form follow the singleton pattern. I can't vouch for this sample, but from the text it appears to do what you want.