Creating Single Instance Form In MDI Application - Check Whether Form's Instance Created Or Not?
Feb 8, 2012creating single instance form in MDI Application. How to check whether form's instance created or not?
View 6 Repliescreating single instance form in MDI Application. How to check whether form's instance created or not?
View 6 RepliesI have a single instance VB 2010 application I know how to communicate with the next instances run through the StartupNextInstance application event. The usual way of working with this is parsing command line arguments of the new instance and continue execution of the old instance. What I would like to do is replace the running instance with the new one. Is there any way to do this other than disabling the single instance property ?
View 1 RepliesI have windows application and a form. If I open a form named "DetailForm" from main form named "Main1" by clicking the button, it should open only once. The problem I am having is, it is opening many instance of the form every time you click the button.
View 8 RepliesI then have an iteration (For Each loop) which lists all of the OUs on our site (set by the filter property). The issue here is within my treeview it lists everything without mimicing the AD structure we have.When searching on this it seems i have to change the search path to be one below the current OU and add it to my child node. I believe the search path is held in my RootDSE??, but when i look for the distinguishedName and try to pass that in i receive an
View 1 RepliesI have a mdicontainer form that summons forms. My problem is when the a user clicks again the menu for that form, it also make another instance of it.
What I did is declare a public class with a public variable on it ex: Boolean isFormOneOpen = false. Then every time formOne opens, it checks first the global variable I declared a while ago if it's false, if it is, instantiate an object of a formOne and then show it. Otherwise, do nothing. Very static, imagine if I have many forms, I have to declare a variable for each form to check if it's already open. Maybe a method that accepts a Form? Or any more clever way to do this.
I need my program to open just one instance of each form, and if the person clicks again on the button that opens a form that is already showing, the form should only be brought to front (probably with the "bringtofront" method). How do I do this?I tried checking if the form "is nothing" before showing it, but if I close it and then try to open it again it doesn't work.
View 4 RepliesI have a form with a button. I want the button to show a new instance of the same form but I don't know what to do. I'm working in vb.net 2010
View 3 RepliesNow I have created this order form but when I click on the ADD button nothing happens. I expect when I click on the item automatically the data is added to my database. i am using SQL Server 2005
View 1 RepliesNow I have created this order form but when I click on the ADD button nothing happens. I expect when I click on the item automatically the data is added to my database. i am using SQL Server 2005
View 5 RepliesI am looking for a way to make my app running in a single instance mode and showing the MainWindow of the first instance when another instance is launched.I do a quick search on the internet but I did'nt find anything to open the MainWindow of the first instance or it was for Windows Form not for WPF.
View 1 RepliesIf you want a instance of an object to be created when a form loads or another class is created, you have two options:
Public class example
private IAmAObject As IAmAObject
public sub new()
[CODE]...
Or like this:
public class example
private IAmAObject as new IAmAObject
public sub new()
[CODE]...
I always use the first one. It's more type work but I think it's neater. How about you people and is there any real difference between the two?
I'm trying to implement single instance application using mutex.the application can run only one instance from a given directory.i tried to implement it in Applicationsevents class but it's not working.I replicated it with a test harness with a single form.my ApplicationEvents.vb code:
Private Sub SingleInstanceCheck(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs) Handles Me.Startup
Dim strLoc As String = Assembly.GetExecutingAssembly().Location
[code]....
it runs multiple instances.Things I am not able change:
1.project setting has "Enable Application framework" ticked
2. ApplicationEvents.vb handles UnhandleException which means i cant have a module as startup.
I have a Parent form that loads a child form and I only want to allow one instance of the child form. I have this on the button to open the form. Stepping through the code with the debugger it "appears" to work OK when the form is open (I say appears because nothing changes) but when the form is closed it doesn't open as I would expect. What am I missing?
[Code]....
assume that i have two forms(form1 and form2)form1 code
Imports System.IO
Public Class Form1
Inherits System.Windows.Forms.Form
[Code]....
in vb 2008 express this option is available under application properties. does anyone know what is its function? does it make it so that it's impossible to open two instances at the same time?
View 3 RepliesIs there any way of restarting a single instance application, which is deployed via clickonce?
View 1 Repliesi am using "Animated Window Effects with "Toast" popup demo" code from the code bank created for jmcilhinney. I put a NotifyIcon control on it and check Make single instance application on the project properties windows. the problem is that every time that i launch the app it creates one instance on the system tray of the app. i can not figure out how to over come this attached is a copy of my project.
View 10 RepliesI have a VB .NET application set as single instance. When I try to launch the application the second time its window is restored to its normal windowed state instead of being maximized (like it was before attempting the second launch). How can I make the application window to preserve its last state?
View 1 RepliesI'm trying to build a single-instance application, but not in the traditional sence. Instead of a simple silent prevention of launching a second application, I want it to send a message to said application so it launches a second mainform in my original process.
(I want some read-only cache (language, style,...) shared, and a few sources like local settings shared, but other then that all resources reside in the mainforms and act as seperate applications.)
(I'm not looking for specific code, more for hints/tips and/or general directions, more specificaly on what parameters do you check process equality, and what method do you use to pass the message? Windows Messages? Sockets? ...)
I have set the "Make single instance application" check box.And when my application version is 1.0.0.0 for example, it is OK and won't load multiple instances.But when I create a new version, for example 1.0.0.1, then I can run 2 instances of my application, when the 1st instance is 1.0.0.0 and the second instance is 1.0.0.1.What should I do to prevent this?
View 2 RepliesHas anyone using VB.NET 2010 been able to create a single instance application? I've followed the MSDN sample but it does not have an Application.xaml file. Converting any C# samples to VB doesn't work as I cannot override the Main sub in Application.xaml (C# calls it App.xaml).
View 2 RepliesI'm writing vb.net code with MS Visual Studio 2005.When running my application I get "foo.exe is already running on this machine".(Even though I'm running faa.exe instead
View 14 RepliesI wish to turn on the Single Instance Application choice in Visual Studio 2008 properties. To do so, I must choose "Enable Application Framework". When I do that, my ONLY choice is to choose a Startup Form, not a Startup object. This makes no sense to me. I have a tray application, and I check to see which form I should load, a logon form, or the main form. But since I am forced to choose a startup form, I MUST load the logon or main form to begin with. But I don't want to. I want startup code to determine which one to load first. So then I am playing with making the OTHER form invisible, even if the startup form, but that is a mess.
View 4 RepliesI'm having this problem with my code and cannot seem to get past it although it was working fine before. The error is "An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object." The code is:
CODE:
I am trying to get information to be pulled out of a database and show in text boxes on another form (frmviewsdets). The error occurs when it gets to the line frmviewsdets.txtsnumber.Text = rdr("StudentNumber") and even when a breakpoint is applied there it just moves on to the next and so on.
I have tried to show frmviewsdets before I pull the data out of the database beut I get the same message.
In my VB .Net code, I am trying to create to launch MS Project Application. Dim prjApp As Microsoft.Office.Interop.MSProject.Application = New Microsoft.Office.Interop.MSProject.Application
But I am getting the exception as follows:
"Creating an instance of the COM component with CSSID {36D27C48-A1E8-11D3-BA55-00C04F72F325} from the
IClassFactory failed due to the following error: 80010001".Note: This exception happens in 64 bit Windows 7 German OS. But the same code runs successfully in 32 bit Win XP (German and English) and 64 bit Windows 7 English OS.I have even tried the following steps in German 64 bit Win 7
1. Running the application in Administrator mode
2. Setting UAC to low.
3. Re-installing MS Project in German 64 bit Win 7.
My problem is when i try to call Application.Run() in a application without a form i get "Object reference not set to an instance of an object." when i run it outside VS. but if ran in debug or release mode it works just fine. i may just be forgetting to setup application right, but ive done it before in this same manor and it worked fine.
Sub main() 'this runs first.
AddHandler Application.ApplicationExit, AddressOf ExitEventHandler
dbg_f("handle added")
[CODE]...
Commented out init_timer and init_ready, and now it causes the same error for the myName line. there seems to be something wrong with class Application. btw theres seems to be something wrong with the forum code formatting.
I'm not sure if "Simpleton Technique" is the term used to call "opening a single instance of a form", so please, by all means, correct me if I'm wrong.I opened a child form using the simpleton technique. The situation is like this:
I have three forms (frmUserProfileManager, frmUserInfo, and frmUAC), and all are child forms of the MDI form, MDIMain.You first access frmUserProfileManager using the menu bar. It opens the form using the simpleton technique:
[Code]...
I think maybe it has something to do with the event (MDIMain_Load)? I feel as if the program is only making a child instance of the frmUserInfo once (since the program only loads MDIMain once). And after I close it (frmUserInfo), it loads outside the MDI. Another thing, how do you kill forms that were hidden using .hide()? Is .dispose() applicable?
I have been making a webbrowser for a while now, everything works well, except i am unable to make the 'open in a new window' button work right. So far i have managed to get a new instance of my form to open with the right url, but i am unable to keep that new form open when the orginal parent form closes.
Code:
Private Sub WebBrowser1_NewWindow(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles WebBrowser1.NewWindow
e.Cancel = True
Dim Href As String
[code]....
I'm trying to figure out the best way to reference a control on a form from within a module. Unfortunately the form is just an instance, so it's not as easy as calling form.control...
Dim ChildForm As New frmSearch
' Make it a child of this MDI form before showing it. '
ChildForm.MdiParent = Me
ChildForm.Show()
That form has an option for printing, which calls another form where certain options are chosen. The print form in turn calls a function in a module, which tries to reference back to the origional form.
childform as new frmSearch -> frmPrintForm -> sub okToPrint (in module Print)
okToPrint tries to reference a listview on frmSearch, but can't find it.
For Each itmX In frmSearch.lstResults.Items
So the solutions I can think of off the top of my head are:
1. Somehow divine which form is the caller of frmPrintForm
2. Pass ChildForm to the frmPrintForm as a variable to be passed on to module Print..
3. Use frmSearch directly instead of using an instance of it.
Number 1 would be my preference, as I don't want to have to pass forms around like that.
WTF, here's my code...
Public Class Form1
Dim BIT01 As Integer = BIT_01.Text
Dim Value As Integer = TB_OutPut.Text
[code].....