I have a problem with showdialog when the showdialog form is being disposed. The Application focus to another program opened in taskbar. if nothing is opened then it focused to desktop.
This will happen when the dialog is getting disposed too early. All of the windows are disabled by the dialog so Windows can't keep the focus on any of them and has to pick the window of another app. Make sure you use the standard pattern with the Using keyword so the dialog object is disposed after it closes:
Using dlg As New FooDialog
If dlg.ShowDialog(Me) = DialogResult.OK Then
'' Use dlg properties
''
End If
End Using
its as simple as this:
form2.showdialog()
me.bringtofront()
Related
I have a WinForms application which uses webview2 to embed an Edge browser window in my application. It works great, but when the user clicks a link within it, it opens an extra "child" window. That's fine too, but if that child window is left open, it causes the web application to timeout, so I'd like to close them automatically after a time.
I tried the common solutions to close open forms, but they only get the top level forms, and never these child ones.
I've tried this code to close them all, but the dynamically opened forms are not closed:
Public Sub CloseAllForms()
Dim FormList As ArrayList = New ArrayList()
'Add all opened forms into a Collection.
For Each Frm As Form In Application.OpenForms
FormList.Add(Frm.Name)
Next
'Now Close the forms
For Each FormName As String In FormList
If FormName <> "frmMain" Then Application.OpenForms(FormName).Close()
Next
End Sub
How can I reference these windows so that I can close them on a schedule?
I have a button in form1 that opens form2. I do this using frm2.show(). It works totally fine for the first time that I open frm2, but when I close frm2 and click on the button in frm1 to open frm2 again, I get this error:
Can someone tell me how to solve it?
Edit: I have a module where I have my database connection and my declaration for the forms:
Public frmGame As New Game
Public frmPlay As New Play
Public frmFinish As New GameFinish
Public frmLogin As New Login
Public frmManage As New Manage
Public frmInsert As New Toevoegen
Where I open the form is just when I click on a button in form1.
Sounds to me like you are Close()ing frm2. Closing a form should dispose it and release its resources, so you can't simply Show() it again. Instead, you need to create a new instance of the object, like this:
frm2=new Form2()
frm2.Show()
If that doesn't work (perhaps because you don't want to re-initialize the form's data members), you could use Hide(), rather than Close() to temporarily hide the form during your program's execution.
If you need to prevent the form from being closed with the X button, you can do this with a few different methods:
The best way to go may be to hide or disable the close button. Read up on This post to get a better idea of how to do that.
You can use the FormClosing event, either from inside frm2 or from the main window. Set the Cancel property on the FormClosingEventArgs object that gets passed in. The problem here is that you will need to provide an additional code path to close the form when you actually want it to close. The CloseReason property of the FormClosingEventArgs object should give you a way to handle that properly. Needless to say, this is probably the riskiest way to do things, since you need this window to close when the application shuts down, but you're also intentionally block that from happening.
You could catch the FormClosed event in the the form that spawns frm2, then create a new instance of the window. Again, you'll need to provide a code path to allow the window to close when the application shuts down.
In all, method 1 is probably the safest. You can close the window with .Close() when the application shuts down, but the user can't close it with the X button.
I'm using vb.net 2013, and I have configured Shutdown mode to "When last form is closed".
On my main form, I have a menu item which has this code to close the application:
Application.Exit
Everything is working fine, except one case:
When I open a specific form, where a Combobox is created on runtime and I've used Addhandler to subscribe to several events.
The combobox is created when pressing a button.
When I open this form and I don't create the combobox, everything is working ok. If the combobox is created, when I close this form and try to close the application using the menu item, nothing happens. The application is not closed and no error message is displayed. (the same situation occurs when I try to close the main form with "x" button)
On the form's (where I have the combobox) close event , I tried to put a line of code:
MyCombobox.dispose()
But the situation is the same.
What can I do? Thank you!
What I do from my little experience is
1.) remove the MyCombobox from its parent control (I'm think this is in your combobox close event).
2.) set the MyCombobox to Nothing
3.) Dispose() it.
MyCombobox = Nothing
MyCombobox.Dispose()
It would be useful to see some part of your code for the close event so we can help you check. More power to you!
Update based on OP's comment:
I have read the following from MSDN: https://msdn.microsoft.com/en-us/library/system.windows.forms.form.closing(v=vs.110).aspx
From this, it is important to note that:
The Form.Closed and Form.Closing events are not raised when the Application.Exit method is called to exit your application. If you have validation code in either of these events that must be executed, you should call the Form.Close method for each open form individually before calling the Exit method.
I have a modal window popup so a user of my application can edit some stuff, then they save it and close the window. When they close the popup window, my parent (main) window gets sent to the back of all other applications on my desktop, and then it immediately gets sent back to the front.
Any idea why this would happen?
In your main form:
Dim frmDlg as New FormDialogToShow
frmDlg.ShowDialog(Me)
The main form should not get sent to the back. The child dialog will display on top of the parent. Without the owner reference, the mainform can sometimes get sent to the back. When you dont specify an owner form and that happens:
Dim frmDlg as New FormDialogToShow
frmDlg.ShowDialog()
Me.BringToFront
(the answer is the same as the first time)
Does your modal form somehow hide itself before ShowDialog line ends? This happened to me and was able to solve it by removing the Hide call from the modal form.
I think I read somewhere here in SO that this happens because Windows does not have an enabled window to send focus to in the active app so it sends focus to the next app instead.
This code seems to solve the problem:
' When closing the subform
' ------------------------
sub_form.close()
main.focus()
sub_form.dispose()
When doing this, my main form does not get sent to the back even when the sub form is modal window.
I was searching desperately to find the answer to a similar problem. I found this to be particularly useful:
Private Sub Frm_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing
Prompting = False
Frm = Nothing
FrmPrompt.Close()
FrmPrompt.Dispose()
FMain.Activate()
End Sub
Activate allowed my main form to not be sent behind anything else I had open.
I'm developing a WinForms app in VB.NET, that handles sets of style data, and when the user clicks on another set's label, it prompts through a dialog "You are leaving this style preset to edit another one. keep changes on this one? [Yes] [No]"
But, I'm facing the problem that, when the user clicks either option, and the dialog closes, everything has to be refreshed, and loading the form again seems a good option.
I've tried putting a public sub on a module, that does this:
Public Sub CloseOpenStyleDlg()
KeepOrDiscardPrompt.Close()
StylesDlg.Close()
StylesDlg.ShowDialog()
End Sub
But as soon as that sub is called from the prompt, it crashes the application. (doesn't show an error in debug, simply crashes) How should I, from a given dialog, close the dialog, it's parent, and re-open it's parent? (which triggers all the Dialog_Load() code of the parent)
Thanks in advance! :)
You need to instantiate the dialog again. If I take your code for example:
Public Sub CloseOpenStyleDlg()
KeepOrDiscardPrompt.Close()
StylesDlg.Close()
StylesDlg = new StylesDlg()
StylesDlg.ShowDialog()
End Sub
When a form is closed, all resources created within the object are closed and the form is disposed.
If you want to reuse the Window instance use StylesDialog.Hide() function instead.