Ensure Instances Of Class Finish Before Main Terminates?
Feb 14, 2012I have a MultiThreading issue and conceptual question using Visual Basic (but it applies to almost all languages). [code]...
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Multithreading - How To Ensure That A Code Is Running On Main Thread
Jan 21, 2012It's easy to do so in objective c but I do not know how to do so in vb.net update:I know about control.invoke. But control.invoke requires a control that may change from program to program. What would be the easier way?So yes program is winform. However I need a solution that does not depend on any specific control. If that's the case actually I do not need things to be run on main thread do I?
View 2 Replies.net - Closing Main Form Doesn't Finish Process In Windows 7?
Feb 23, 2011I have an MDI form as the app start object.I don't think is related, but in the Form closing event, I check for some condition, and if it's true, I ask for confirmation before closing:
Private Sub FormBackground_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
If (e.CloseReason = CloseReason.UserClosing) Then[code].....
So long, everything works fine in my development machine, which runs windows XP.However, when deploying the application in a windows 7 machine, the message box works correctly, showing itself whenever it should, but after the form is closed the application keeps running in the background. This happens whether the form closes directly or asks the user first.I have fixed it putting an End instruction in the FormBackground.FormClosed event, but it doesn't feel good.
Use A Progressbar To Show On Main Form And Then Finish When Next Form Is Loaded
May 12, 2009I am trying to use a progressbar to show on main form and then finish when next form is loaded, I have got this code.
1. When I click on button, it must open next form, but the next form must only open when the data in my list box has been loaded from Access Databse. When I run my program, it only shows the progressbar and don't open the next form.
Main form code:
Public Class Main
Dim PB As ProgressBar
Private Sub main_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
End Sub
[CODE]............................
Defining A Class For Multiple Child Class Instances?
Feb 10, 2011I have created a class for a Sports Facility. A facility has a Name, Status, Notes, etc as members of the class. This works well, I can create a new instance of an exisitng Sports Facility from the database, create a new instance, etc. All working well.What I am stuck on is accessing a list of Sports Facilities. I know I can create a new list by doing
Dim List As New List(Of Facility)
For Each fRow As DataRow In ds.Tables("Facilities").Rows
List.Add(New Facility(fRow.Item("FacilityID"))
Next
Multiple Instances Of Class?
Mar 29, 2010I have the following problem. (VB.Net 2008)I have created a class (myFirstClass). In this class there are a lot of calculations being made wich gets fired by events in that same class.Now i want that same class to be able to fire more instances of itself. However i noticed that each time i fire an event from a Sub the program waits till the event is finished before going to the next line of code. This is a problem since i want the event wich fires a new instance of the class to fire it and forget about it.
View 7 Replies.net - Allow Math To Occur On Instances Of Class?
Nov 27, 2010Is there some interface I can implement to allow basic comparisons and math to happen as it would an integer?
For example, let's say I have the following class:
Public Class Something
Public SomeBigNumber as UInt64
End Class
I would like to do something like this:
Dim SomethingA, SomethingB, SomethingC as New Something
....
If (SomethingA-SomethingB) > SomethingC Then
'Do stuff
End If
I was hoping to be able to implement some interface (if that is even the right term for it) that would return the UInt64 contained in the class for comparison and math, if possible.
Added To Each UserControl (different Instances Of The Same Class), A Little Map?
Apr 28, 2009I have a form whose purpose is to let the user to load map files.The form may manage a variable classes of maps, and each class have his own UserControl.To make it more user friendly, I added to each UserControl (different instances of the same class), a little map, showing a small picture of the map, and some data, as bound coordinates.
The problem is, that it looks really ugly. The maps are so big, compared with the rest of the UserControl (who contains just a button and a textbox to search for files).I wish to fix it, but I din not see an elegant way to include the pictures and info.I attach a form screen capture with two UserControl.I would like to get some tips for more experienced users. There are some guidelines?
Creating Instances Of Own Class At Runtime?
Sep 3, 2011info on creating instances of my own class at runtime. Simple project for family recipes but would like the option to add new recipes with new instances of my own food Item class at runtime. Creating my own class,no problem. Storing the data in an XML file, OK on that as well. My issue is creating new instances of different food item class as I use this program over time
View 13 RepliesMultiple Instances Of A Custom Class?
Feb 15, 2009I have a sub that runs on a button click which I want to create a new instance of a custom class and add it to a list of already created instances of this class. I want the result to be a List Of collection of all of my class instances.
My problem is that each time I run the sub, it simply 'overwrites' the first instance of the class and adds a copy of it to the list instead of writing a new instance. My code is along these lines
dim objFixture as new clsFixture
For n As Integer = 1 To intNoOfChannels
objFixture.SetChannelAddress(n, intCurrentChannelTotal + 1)
intCurrentChannelTotal += 1
next
lstFixtures.Add(objFixture)
Passing Variables Between Instances Of A Class
Jun 17, 2009I created a program a while back, in the traditional VB.NET way by drawing a bunch of forms. I have started playing around with creating the forms at runtime using classes. I have a placeholder form called frmStartup which merely calls the CreateLogin() sub from the CreateFormClass. The CreateLogin() sub creates a new blank form, then calls the grpbxLogin(), btnSave() and btnExit() subs from the FormElementClass which adds all the buttons and textboxes to the form. Within the FormElementClass, I have associated btnSave and btnExit with event handlers. These even handlers call subs from the DataProcessingClass. The event handler for Exit works just fine.I am having a problem with the Save event handler. Precisely, I don't know how to pass either the username or password from the Login form to the btnLogin_Click() sub in the DataProcessingForm. I have tried using Me. and frmLogin., but the program doesn't see either of those. If the Login form is an instance that is disposed of once another Sub is called, then it won't exist later on to call from. I have tried declaring variables and passing those along to btnLogin_Click, but no matter where I put it, the program doesn't see txtbxUsername.Text or txtbxPassword.Text. Not even from within FormElementsClass, which is were the boxes are created.Any ideas on how to pass variables in this case? I am not even sure what you would call this such as passing between classes, or passing between instances.[code]
View 9 RepliesRepor Declaring Class Instances?
Oct 20, 2008I've decided to forget the d@mned custom code because everything I do with comes up with errors I don't know how to fix and it seems no one else does either. Or they do and they're keeping to themselves.
I put the functions that I needed to use in a class called MsgBoxOperations. The file name is MsgBoxOperations.vb In the report, up on the standard bar where file, edit, view, and all the other stuff is, is one that says report. You click that and go to report properties and it brings up where you can name the report and put in custom code...(hate custom code right now...) and where you can put references and class instances. Clicking on the Reference tab brings up wher you put in your references and classes.
In the classes area it asks for the Class Name, which I put in MsgBoxOperations, and the instance name of that class, this case mbo. I get that far and put in those two things and save it. Then I go to the textboxes where the values need to be. I put in the text box: =Code.mbo.GetStartDate
I've already tried taking the Code. part out and it screams that mbo isn't declared. So it does have to be there. I go to run the code and comes up with this error: QuoteError in class instance declaration for class MsgBoxOperations: [BC30002] Type 'MsgBoxOperations' is not defined.
I've posted before and still have received no help or someone tried to help but then stopped when their suggestion failed and then no one else wanted to help. I've googled this problem to the point where every link that it comes up with I have already clicked and found their information useless. I've got a freaking migraine because of this issue and have been in tears over it more than once.
Alphabetize An Array Of Objects That Are Instances Of A Class?
Nov 1, 2011I have an array of objects 2000 that are instances of a class. I want to alphebatise these objects by a detail of the class.
View 1 RepliesC# - Respond To Events From A List Of Class Instances?
Jan 21, 2011I have a .NET class, InstrumentConnector, that has an event, StatusChanged. I want to create several instances of this class (each class handles a separate file) and respond when the StatusChanged event is raised any instance. How would I do this in .NET? Do I want to create a List(Of InstrumentConnector) or a similar IEnumerable? How do I write the event handler to respond to a particular instance's StatusChanged event?
Here is the InstrumentConnector class and the module with the StatusChanged handler:
Public Class InstrumentConnector
Private _inProcessDir As String
Private _doneDir As String
[Code].....
Creating Instances Of A Class That Has Several Readonly Properties?
May 24, 2011What is an elegant way to create and initialise instances of a class that has several readonly properties? Passing all values in a constructor would not be very convenient.
The purpose is that instances are immutable after initialisation. However if the constructor is not used for initialising all the property values, then how can the readonly properties be changed from another class?
VS 2010 'Infinite' Public Instances Of A Class?
Jan 24, 2012I'm a little out of my comfort zone here having programmed in VB6 quite a few years ago things have changed a lot since then.My issue is I have a class that I've built which works with no issues but I would like to be able to keep a 'handle' of some description on this class so I can also make adjustments to it's parameters when the user changes something. My problem is that I need to do this for an unknown quantity of these class instances.
In the VB.Net language how would I create an instance of this class that could be accessed by any Sub within the application and each instance created can be individually accessed by specifying some sort of identifier?
Creating An Array Of Instances Where Instance Could Be Base Or Sub Class?
Oct 31, 2011I have a class structure and am attempting to create an array of object instances from the class some instances are parents and some are children Code snippets,
Parent Class object
Option Strict On
Option Explicit On
Public Class cTransportItem
[code]....
Class Has Been Create By Main Class Only?
Feb 27, 2011I'm try to create a class has been create by main class only by protect sub New but how do I create it ?
Public MustInherit Class Rune
Protected MustOverride Function Create() As Rune
Public Shared Function Factory(Of T As Rune)() As T
'I can't use "T As {Rune, New}" because Sub New isn't Public
'Return (New T).Create
End Function
End Class
[Code]...
MovablePictureBox - Set The Flags In All Other Existing Instances Of The Class, When It Is Set To True In The Selected PictureBox?
Apr 17, 2010if I have several of these movable PictureBoxes added to a Form (Form1) and want to display a selection rectangle only on that PictureBox, that is just selected,then I think I should use a flag to mark whether a PictureBox is selected or not. The flag could be used in paint event to decide,whether the selection rectangle is to be drawn or no .To add a flag property to the new class is no problem. But how can I set the flags in all other existing instances of the class, when it is set to True in the selected PictureBox?
Object Oreinted Random Failure - Define Two Instances Of Class And Configure ?
Oct 27, 2009I am having a problem with a and OOP class i made that contains a sub that creates random integers.
Problem is if i define two instances of this class and configure them(name in this case) then they both display different names but the random integers are ALWAY the same. in this case having the integers the same kinda kills the idea of the program.
Is it possible that the random part only every works for one class, but if .NET is fully OOP then this should not be possible... right?
Some of my Code (broken down to something smaller) i will display for obvious reasons.
Code:
VS 2010 Sorting A Listbox (after Trying To Copy Class Instances Properties To A Temp List)
Jan 25, 2012I'm trying to figure out a way to sort the entries of a listbox... but in a different way instead of the obvious one (sorted property). First of all, I need to explain how the items are populated at first:
[Code]...
VS 2008 Program Terminates Itself
Apr 19, 2012I have an application which I wrote in vb.net. When the application starts it connects to mysql database online to get some data and once done it proceeds. The problem is at times it gets stuck in the mysql thing, I mean after requesting nothing happens and this causes my program to lock up. Is there a way the program can determine that x seconds has elapsed and it has not got data, so self terminate it.
I tried using timer to perform this action but as the program requests for data, it gets stuck, I mean it locks up and thus timer also locks up and only after task is done everything resumes. I wanted that when the program is about to start request, I can start a timer and determine that x seconds has elapsed, so now terminate the application.
[Code]...
How To Call A Class From A Main Form
Mar 5, 2010How would you call a class from a main form? In VB6 you would call a module by just simply calling the module name.
View 2 RepliesHow To Refer To Main Window Class
Sep 6, 2011I created a modal dialog as a WPF window that changes some settings in the main window application. How can I refer to a member of the main window?
View 2 RepliesIDE :: Program Terminates Without Exception Details?
Nov 17, 2009After dealing with the pain-in-the-____ error "The path is not on a legal form" witch only occured after dragging a file system watcher onto the form, by creating the file watcher in the code. When an event is raised, i have to tell the user what happened. I can do this using messageboxes, without any problem. But, when I wanted the output to be displayed in a textbox, the program terminates without any warning. Here is what my code looks like:
Public Class Form1
Public watchfolder As FileSystemWatcher
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code]....
Class Not Registered While Loading Main Form
Apr 1, 2009We have a Dell laptop used to run an in-house VB.NET program. It got a virus. We had to wipe the hard drive and reinstall Windows from scratch. We use Windows XP Pro, which is what was installed on it before. But now our VB program won't run. After trying and despairing of getting remote debugging to work, I actually installed Visual Studio 2005 on the machine, just long enough to get information about what was making the program fail. And the failure was most peculiar. It isn't in our code. It's in the VB setup code that loads the main form. And it says, "Error loading form: class not registered."The gory details are given below. Now here's the strange thing. Not every VB.net program fails on this computer. And the program that fails, fails only on this computer; it has run successfully on several other Windows XP systems with .NET Framework 2.0 installed.[code]
View 3 RepliesMain Difference Between A Class And A Type And A ValueType
Dec 17, 2009what's the main difference between a Class and a Type and a ValueType.and is a Delegate a Type? or an eventhandler/event (the actual event itself)is every object a type? or is it only true in VB
View 3 RepliesSet And Get A Value From A Class Property Within The Main Event Of A Module?
Jul 8, 2011the project uses a submain as startup object which is located in a module, thy so the application will be started in tray. Within the main() event i need to deserialize a xml file and with it set the properties of a class and then set what the application will do.The problem is, after I deserialize it and put set the property values I try to get them in the same event(main) but when it gets the value it returns as nothing(if string) or 0(if integer) but in the debugging i saw it setting the values.Is there a way to do that, within the main() event of a module to set the properties of a class and then get them without being nothing/0 ?
View 6 RepliesUse The Update In The Main Class To Access The List?
Jan 15, 2012i need to use the update in the main class to access the list in the footballadmin and then display each in a list box but i cant get it to work.
Imports Football
Public Class FootballAdmin
Private fTeam As List(Of FootballTeams)
[Code]......
VS 2008 Can Call A Class From Main Form
Dec 14, 2011As of the moment I have 24 buttons that are keys to a piano.24 of the button codes have a call method that calls the note to be played.24 of the private subs that are called have an .wav audio playback command within them. I was hoping I could move the .wav private subs into a separate class, and just call them from my main form, therefore cleaning up the lines of code I have at the moment. [code]That example only counts for one Button "The Key of C", and the audio file that is called with it. Multiply that by 24 and you get a big mess of repetitive junk.Can I move the audio subs into a class and call them from my main form?
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