I created a custom class which creates a PictureBox.
The Class looks like this:
Public Class Layer
Dim pb As New PictureBox
Public Sub New(ByVal parentPB As Panel, ByVal parentContex As ContextMenuStrip)
[Code]....
How do I add event handlers to this picture box?
is it allowed to use more than one Sub to handle the same event ? For example , may I have 2 separate subs to handle the Load event of a form ? Will they fight each other ?I have tested it and it seems to work fine , nevertheless I thought I'd ask you . In case you wonder , there is no great deal , I just want to copy the same lines of code in more forms so I am doing it just in favor of the looking aspect .
View 5 RepliesI have two forms, A and B. A shows B modally. B can exit normally, or can exit because of an exception. Therefore, I have this code in a method in A:
Dim nf as New B
Try
nf.ShowDialog
Catch ex as Exception
'Whatever
End Try
Now, B has some event handlers that handle an event that is raised when a certain value changes. I just found out that if B exits because of an exception, rather than a normal exit, the event handlers are still hooked up. To figure this out, I added a private string variable, and in the constructor of B I added a line to put a GUID.NewGuid.ToString into the variable. When I run this, I can pause in the event handlers I mentioned earlier, and look at the private variable to tell which instance of B is actually handling the event.
Under normal operations, there is only one instance of B. However, if B exits due to an exception, I find that the instance of B which died due to the exception, handles the event before the new instance of B is even created. At a slightly later date, the user presses a button that will cause the event, and, due to something hard to explain, the event gets raised six times, three each from the old, undead, instance of B, and three times from the new, visible, instance of B.
I think that the entire problem I am having is that the event handler is triggering things that cause the two instances to pinball events back and forth between the two of them in a complex recursion. My problem is how to get rid of that undead instance of B so that it stops handling the events that are raised. I tried putting nf.Dispose in the Catch handler of the above snippet, but that did nothing.
i want to automatically add all the events of the activeform under try catch block.i am using a simple code which puts the selected code of ActiveDocument under try catch ( using DTE.ActiveDocument.Selection )i have to manually select each event's code and apply the macro, which does not seems to be a very good idea.
View 1 RepliesWhen I utilize AddHandler in VB to add my own method to the Click event :
AddHandler Button.Click, AddressOf myButton_Click
I see that my code executes last - after other event handlers for the Button_Click event. Is there a way to insert my event handler in front of other events so that it executes first?
I would like to do something like the following:
Public Class Form1
Public Event Evt1(ByVal c As c1)
Public Event Evt2(ByVal c As c2)
[code]...
However, it seems to be invalid syntax, as the signature of OnEvt1OrEvt2 doesn't match that of Evt2.
Edit: The above code seems to work fine for everyone but me, but it doesn't compile for me in VS2005 SP1.The error message is something like:Error BC31029: The method 'Private Sub OnEvt1OrEvt2(c As WindowsApplication1.c1)' can not handle the event 'Public Event Evt2(c As WindowsApplication1.c2)' because the signatures do not match.
[code]....
event handlers need to exactly match the event signature?
View 2 RepliesI have a panel control on a win form, to which I dynamically add a custom control.The custom control inherits UserControls and in the New() sub, I assign the control a GUID.When a control is added to the form, a variable of type List(Of T) holds the details of where i put the control and the size of it.
Within the custom control class there is a delete method. When the method, which deletes the custom control, is run I want the details of that custom control removed.I think I need to use event handlers but I do not know how to handle these when the controls are added dynamically.
I want to set an event handler only if this is not set:
If GetHandlers(MyWindow.Closed, AddressOf MyWindow_Closed).Length = 0 Then
AddHandler MyWindow.Closed, AddressOf MyWindow_Closed
EndIf
I have a problem, in Winform or mobile developing, When I newed some buttons in my code(never drew on the form), how can I add the click events to them and use it?
View 5 RepliesHow do I create an event with many handlers. I use the followingo code but it failed. Am I missing something?
Protected Sub myhandler_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CrdCb1.CheckedChanged, CrdCb2.CheckedChanged
End Sub
[code].....
how many handlers are tied to an event?
View 2 RepliesI was editing my code and after deleting a button from a toolstrip vs locked up and trashed the designer.vb code. Now I have all my form code but many of the control objects (e.g. buttons, listviews ..etc) have been deleted. I've re-added the control but none of the events associated with the control (e.g. _click) work. If I delete the event handler code and add a new one the paste in the code it works fine
View 10 RepliesProblem: I have a document class which contains a list of objects. These objects raise events such as SolutionExpired, DisplayExpired etc. The document needs to respond to this.
Documents can sometimes exchange objects, but a single object should never be 'part' of more than one document.
My document class contains a bunch of methods which serve as event handlers. Whenever an object enters the document, I use AddHandler to set up the events, and whenever an object is removed from the document I use RemoveHandler to undo the damage. However, there are cases where it's difficult to make sure all the steps are properly taken and I might thus end up with rogue event handlers.
I am trying to do sum custom events in a Class. My class listens for a UDP Broadcast, I want to Raise and Event when a message is received to display the message from a windows form.
Here is my code.
Public Class UDP_Broadcast
Public Event NewMessage(ByVal Message As String)
Public Port As Integer = 2456
Public Sub Receiver_Load()
Dim t As New Threading.Thread(AddressOf listen)
[Code] .....
I have a form that is derived from a base class. When the form is created a behavior class is also generated that handles event management, bindings, etc...
I create a form instance(FormFoo). When the associated behavior class is created it has a method in it with a signature of: grid_EventA(....) Handles grid.eventA
I want to handle EventA in FormFoo instead of the behavior class so I remove the handler that was generated in the behavior class and add a handler that points to a method in FormFoo. This all works just peachy. The event is properly handled in FormFoo only.
Next I instantiate a modal form(FormBar) via a button click in FormFoo. I then close FormBar. Now we have a problem.
When eventA fires it is now handled from the Event handler in FormFoo AND in the behavior class associated with form foo(bad).
Is the event handler in the behavior class(grid_EventA(....) Handles grid.eventA) getting resubscribed when the form gets focus again? I don't understand how that event is getting resubscribed.
Alright my goal is to test to see if the user has dragged a label over a button. I have add event handlers for MouseMove and ButtonEnter, the trick is that i dont want the buttonEnter sub to fire unless the user is actually dragging a label.Dim dragging As Boolean = False
[Code]...
I thought would work but because the user is dragging the label the mouse never actually enters the button field. I also tried doing lbl.location = button.location... but unless the label and the buttons are the exactly the same size in exactly the same location then the event wont trigger.
Isn't the a quick way to add event handlers to a program through the compiler? I'm trying to make a label change color when it's moused over.
View 5 RepliesI am making an interface that has a number of events defined in it. When I implement the interface in a class the events will show up. I want to force a class that implements my interface to also have to make the event handlers too. I don't care where the class raises the event, but I want them to have to define what happens once the event is raised. Is this possible and if so, how do I do it?
View 1 RepliesHow do I avoid an event from being handled twice (if is the same handler?)
Module Module1
Sub Main()
Dim item As New Item
[Code]....
I want the event manager to detect that this event is already handled by this handler and so it shouldn't rehandle (or readd) it.
I've started working with the backgroundworker class to try and keep the UI responsive while I make some expensive API calls. One of the API classes (details here[msdn.microsoft.com]) has its own event handler which I am using to update a progress bar in a small form that pops up. So I'm looking to use the PublishPackage command in a bgw thread and update a progress bar on the UI thread by using the ProgressHandler method.
[Code]...
in my project I create buttons dynamically
For i = 0 To btns.Count - 1
btns(i) = New Button()
btns(i).Text = names(i)
btns(i).Size = New Size(btns(i).Text.Length * 15, 25)
[code]....
I need to specify a handler for each button that retrieves the button text how can I do this?
Visual Studio 2010 I am trying to learn Caliburn Micro. The sample project is presented in C# only (and runs OK) I have tried several on-line C# to VB converters, without success. Well the conveersion runs without error - - - but the Visual Studio editor chokes on the results. The principal problem seems to be with (what looks to me like) a Lambda. Advanced code conversions are really tough in any case, - but when you do not know C# nearly impossible.
[Code]...
I need to be able to trigger events when a user clicks on a radio button that is generated within an control on my page.I've added an OnSelectedIndexChanged handler to the RadioButtonList and created a function in my code behind that should handle the selection of the RadioButtonList's ListItems, but I don't know how to pass a value to that function.Here's my code:
<asp:Repeater runat="server" ID="rptQuestions">
<HeaderTemplate><table width="100%"></HeaderTemplate>
<ItemTemplate>
[code].....
In VB .NET, when you call RaiseEvent X(), is the function that handles the event X processed asynchronously or synchronously. I was under the impression that RaiseEvent and the processing of the event were Synchronous unless created explictly on another thread. I've been told otherwise though.
View 2 RepliesI have a problem with running code in the right order. What I am trying to do is updating a session state variable when I press a button. When I run my code it always runs the event handler for the button after my page_load function.The reason why I need to run it after page_load is that, thatI add a line to the textList. Which the loadGui() should add to a table. The table has a remove button for all lines so the loadGui() function can not be added later becuase then the event handler of the remove buttons wont work.
User press the add button which add a row in the TempResponse Session(TempResponse) gets updated loadGui() runs and includes the newly added row
Sub Page_Load()
[code].....
I tried to use this code in the form:
AddHandler MyControl.MouseDown, AddressOf StartDrag
This wont give me an error, but it doesn't happen anything when I mouse down on the Control.
the same doesn't work if I put it in the user control.
Private Sub StartDrag(ByVal sender As Object, ByVal e As MouseEventArgs)
Dim Box = CType(sender, Control)
Box.Tag = New DragInfo(Form.MousePosition, Box.Location)
End Sub
I created a button in DatarGrid. Now I want to click that button and only when I click the button should the event be fired. Actually I want to Delete that particular row once the button is clicked. However, when I click the button, the Event: CellContentClick of the DataGrid gets fired. And that means if you click anywhere on the Datagrid, that even will be fired, and that makes no sense to put a Delete button. So I want to keep the Delete button and once the Delete button event gets fired, the record gets deleted.
View 3 RepliesI'm not seeing anything about event handlers for dynamically created controls.. and I could have sworn I had once before. I did see one post about the topic, but it was just replied by asking for some posted code, so as in a preemptive move..
Private Sub buttonCreate()
Dim newbutton As New Button
newbutton.Height = 39
[CODE]...
Here's what I'm trying...
Private Sub newButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles newButton.Click
End Sub
Here's the errors I recieve...QuoteHandles clause requires a WithEvents variable defined in the containing type or one of its base types
Is thier a way to sort the event handlers within a module/class/form Etc? The IDE add the next event handler and the end while I would like it to put it in place. For example I have already write some event handlers for a textbox named txtEmpname and I have another text box named txtphone. they are ordered in the module in the order created.(i.e. the txtempname_Gotfocus then the lostfocus, then txtphone_gotfocus) Now when I want to add a clcik event for the txtempname the IDE put it at the end while I would like it to put it just before the txtempname_gotfocus.
View 2 Replies
