I want to have a collection of a class which inherits picturebox, with a couple of extra properties, so essentially the same. Only I get an error at runtime saying : 'An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object.' Here Is my code, I know that the error occurs here :
I have a windows application which raises a particular event.I need to create a COM callable class whic will allow VB 6.0 to subscribe to this event.I have done a fair amount of research on this and am confused as hell.
can I call shared events contained in one class from another class?
for example:
logonclass.vb : handles login logic and authenticates against database logonmanager.vb: hold current user reference and some logon and timeout events Logon.vb: A form with a submit button.
I would like to do something like this but I can't get the compiler to agree with it
If VerifyEntries() Then Try privLvl = LoginClass.AttemptLogin(txtUserName.Text, txtPassword.Text)[code].....
If this isn't the proper way to wire things together let me know so I can learn to structure differently. In my planning it seemed like I was raising a lot of extra duplicate events from my logonclass to my loginmanager class. Then the loginmanager had to raise it again for the main form to see the change event. It got me thinking that if I publicly shared the events and could raise them from wherever then it would cut down on the amount of events I needed in code and the amount of them flying around at runtime.
I am currently trying to make a calendar project it has 2 user controls one is the calendar and the other is the calender day control. When the month changes in the calender control I need to raise an event in daycontrol to update any holidays. In the calendar control I have the following code for the event:
Friend Event MonthChanged() Public Sub New() ' This call is required by the Windows Form Designer.
I have a TAPI program that is very similar to [URL] I have a delegate ...
Delegate Sub TapiEventCallback(ByVal dwMessage As TapiEvent, ByVal dwParam1
[code].....
From my program TAPI will call the number. My problem is that its not raising any events. I really need CallStateChange. I raised it from address and moved it up to my TAPI Manager. I put break points everywhere and I can not get anything to raise.
My windows application needs to raise an event in a COM callable assembly so unmanaged code can pick up on the event.I am sick of this. All the crazy tags required for COM callable is doing my head in.
I'm creating macrobutton fields in Word by .NET to add fields. I need someway to figure out when a field is copied and pasted. Is there a kind of event which will be reased within Word to .NET?
This is the code to generate the fields:
[Code].....
General I need to add a field to Word with a given name and a guid and when it's clicked, moved, copied or pasted. I need an event to do something with it.
My application has 1 main form and three other forms which raise events to my main form. I noticed that the memory starts at 77,000 K and increases substationally over a few hours maby be to 250,000k and ever increases.The main form has a dataset and a bound datagridview which gets refreshed with data. Basically it's a taxi booking application. The booking form raises an event to the main form and the main form refreshes the jobs and displays them on the dgv.
I'm trying to write a wrapper to a service, which will be used by an existing VB6 project. I've got most of the basic framework working, except for one important aspect: I can reference the wrapper in a VB6 project and subs/function calls etc. work as expected, but events do not. The events are visible in the VB6 app, but they never fire.
VB.NET Code:
Public Event Action_Response(ByVal Status as String) Public Function TestEvent() RaiseEvent Action_Response("Test Done")
[Code]....
So, the cmdTest button code prints 'Done' as expected, but the Action_Response event doesn't fire. Is there something else do I need to do to get the event to fire?
I am running a class(gamepad handler) that uses many child threads to check for key input and the like then it raises events to my form to sort out the needed reaction, Is there a way to make the event raises on the same thread as the class itself.
the question is really what is the correct convention (style) for raising and handling events. When a button is clicked it is generally handled by this method. [Code]
I have recently been trying to follow this convention by creating my own EventArgs class and inheriting the system.eventargs, Then adding my own properties. The problem is as my projects get bigger/complex I seem to be writing multiple eventarg classes. I then decide to try and create a generic eventarg class but this then seemed pointless thinking it would be easier just to pass the object directly instead of wrapping it up in "someEventArg" i have created.
I have a custom (inherited) TabControl which adds Drag/Drop functionality to it, so that one can drag the tabs around, either within the same control (to re-order them) or to and from other TabControls. I've noticed some time ago that my TabControl however was not raising its MouseClick and MouseUp events (or actually: it is not calling its OnMouseClick and OnMouseUp methods, which comes down to the same thing). I've been struggling with this problem for a long while and I finally figured out what is happening. I'm no closer to figuring out what to do about it though... The problem seems related to the drag drop functionality. I have this code in the OnMouseDown method (which is raised as usual):
Problem that you may have when dealing with two objects that are raising some events. Here, to make it obvious, I am closing the form, but the problem can be experienced with any other 2 classes event. First, what is the problem !
Let suppose that by pressing a button, you want to raise a custom event, then execute a method and then close the form
In that case, you may use a code similar to this
Event BeepIt()
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click RaiseEvent BeepIt()
long story short, I have created a ListView type control, using UserControls for the parent control and the ListViewItems. Most the of the control is written and works fine, right up to the point where I tried to replicate the 'Control.SelectedItems(0).Index' property and the 'SelectedIndexChanged' event.
Each child object knows its index value, and could pass this value via the SelectedIndexChanged event (assuming this is how it works in a normal ListView control -- user clicks on an item, and that item fires an event updating the selected index value in the parent object).
How does the child object raise an event in the parent object? I have a feeling this could be done with Delegates, but I'm still learning about their usage.
figured out a different way to code it that _should_ work around the problems people pointed out before.... but one problem is still the same, the examples I find to code pieces of this are all for old versions of visual basic, and don't workI'm a firefox extension developer. I wrote an extension to allow both private and normal browsing windows simultaneously by having two firefox processes. I figured out a way on the Mac to raise the private browsing process when appropriate... it looks like visual basic is the way to do it on Windows... so I'd like firefox to run a visual basic program that does the following:Look through the process table for all firefox.exe processesFind out the process id of the process that called the visual basic scriptThrow out the process ID of the parent process... now we should just be left with the "private browsing" firefox process
I'm trying to use mockling with VB10(VS2010) to improve my unittesting. I have a C# lamda expression example but I don't know how to implement this in a VB lamda expression? v => v.Load += null The full Moq to raise the load event would be view.Raise(v => v.Load += null, EventArgs.Empty) .Net Developer
I am developing a form application in VB .Net with a main thread and two other threads that reading values from two serial ports, do some work and raising events to return values when each thread ends.The handlers for the events are in my main thread.Is there any possibility the two threads to raise events the same time or some other event (button click event for example) raised the same time with a thread finished event? What happened then? Is there a way to make asynchronous event raising?
I am using Visual Basic 2005 Express and have 8 PictureBoxes on the Form.. When the user Double-clicks any of the Picture Boxes, the path of the image needs to be passed to a Subroutine..As of now, I have a different event for each of the PictureBoxes.. I was wondering if there is a way such that I can use a common event. i.e. if a user double-clicks on any of the picture boxes, the same event is raised ?
I am using following code to raise UAC window. It works fine but my form that contains button to raise this window is shown twice. I mean if I put it in CopyFiile Button, when I click this button, it raises UAC windows, copies file, gives success message and then opens another instance of the same form that contains copyfile button.
Dim proc As New ProcessStartInfo proc.UseShellExecute = True proc.WorkingDirectory = Environment.CurrentDirectory
I'm writing a custom textblock control thats populate hyperlinks and raises event when clicked to hyperlink.
I wrote this code but I got stucked.
My code is :
Imports System.Text.RegularExpressions Public Class CustomTextBlock Inherits TextBlock
[Code]....
This code gives error at RaiseEvent Klik(sender, EventArgs.Empty)
Error is : Cannot refer to an instance member of a class from within a shared method or shared member initializer without an expliticit instance of the class.
Is it good practice to store sub-collections of item X inside a parent collection of item X for caching 'filter-queries' which are performed on the parent collection? (They won't be used together (as in color AND type).) Or is it also ok to just Loop over the collection and return the correct entities in a temporary collection?
I'm trying to use certificates to sign documents. The first time that I sign, the OS prompts a dialog for user to set the PIN, but the next times it doesn't. For security reasons, I need that every time that I sign, the OS asks the PIN to the user.
This is the code:
''// create ContentInfo Dim content As New ContentInfo(bytesContenido) ''// create a signer
I am trying to get a progress bar to update on my Form while waiting for a process to complete but could not get my progressbar control to update.
First of, I have tried to fix the problem for a day and a half now looking at various codes and examples in the forums but I'm afraid I probably do not have the necessary VB skills yet to troubleshoot my own code. I believe I will be able to eventually fix this after I am done with my VB book
I've attached the relevant part of my code below and the problem is that I can see my DoWork event firing off and changing the time and percentage that I want to pass on to ReportProgress() and the ProgressChanged handler. However, the ProgressChanged handler is not raised until after my Do Loop is done.
Imports System.ComponentModel . . . Public Class Form1 Private WithEvents TestWorker As System.ComponentModel.BackgroundWorker
[Code]....
Again, I can see the ProgressChange fire but only after my work (diagnostics) is complete so my progress bar is either 0% or 100%. In Dowork, I can verify that the progtimepercentage variable is indeed changing and ReportProgress is called but ProgressChanged is not being raised until after the job I wanted is done.