I have declared a Sub that is meant to trigger when the listbox 'lstStudents' is double-clicked. However, it does not trigger when this happened. There can't be an error in the code itself as it is auto-generated. Why does the code not function as expected? The code is below:
Private Sub lstStudents_DoubleClick(sender As Object, e As EventArgs) Handles lstStudents.DoubleClick
Msgbox("test")
End Sub
The message box is only present for testing purposes.
Could You try to delete that previous "lstStudents" and add new one then apply the "ListBox1_DoubleClick" on it again to make sure it works.
Otherwise let us know what is going there because I think your code is normally and it should be working 100%.
Related
I have a datagridview in which I want to insert a button for removing the selected row. I created without any problems the AddRow Button and, following the same idea, I tried to create the RemoveRow button with the following code:
Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click
DataGridView2.Rows.Remove()
End Sub
When I start debugging I'm having BC30455 error, about not specified argument. What am I doing wrong? I tried to find out here in the forum but I've found only sth about C# and not VB.net
Best regards and thanks all are gonna answer me.
Newbie here :)
In order to achieve a transparency-type effect for pictureboxcharacter1 on the background, I have set pictureboxbackground1 as its parent.
this works fine.
For the second picturebox (on the same form) I tried the same thing and set pictureboxbackground2 as its parent so it would look transparent over pictureboxbackground2. However when I debug the application pictureboxcharacter2 disappears and only pictureboxbackground2 is visible.
the code I have is:
Private Sub Form2_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Me.pictureboxcharacter1.Parent = Me.pictureboxbackground1
Me.pictureboxcharacter2.Parent = Me.pictureboxbackground2
End Sub
Really strange: if I put pictureboxcharacter2 on pictureboxbackground1 in the designer tab, while debugging it shows up on picturebackground2 and transparent (like how I wanted it to be)??
Does anyone know what's going on at all?
Please I'm NEED any help I could get
Is pictureboxcharacter1 and pictureboxcharacter2 one over other ? If so try making the one be other's parent.
Have a play with bring to front option and see if that works.
I'm looking to call a pre-existing event handler subroutine from the form_Load event handler.
But the below doesn't work because control doesn't come back and I want to do more.
UPDATE:
I'm new to this so I don't know what the proper protocol is but...
The reason for the non-return was that a statement like the below ended the subroutines execution.
If aLabel.Tag = 1...
the fix was adding New to the declaration to create an instance of it, ie..
changing....
Dim aLabel As Label
... to ...
Dim aLabel As New Label
I'm surprised I didn't get a warning but instead they just abruptly stopped execution of the sub. That wasn't very helpful :)
Thanks again for your time guys...
(Maybe this question should be deleted now that it has served its purpose)
#konrad #karl
END OF UPDATE
What doesn't work is....
Private Sub Form1_Load...
button1_Click(sender, e) 'But Control doesn't come back.
end sub
Do I change the sender to something?
Thanks in advance
Dave
Invoking event handlers like this is a bad idea, because you are trying to simulate the event context by making sender and/or EventArgs be something else.
Instead, put the logic that you want to invoke into a Subroutine or Function and have your Form1_Load method call that; likewise if you really do have a real click event handler, then that handler code can call the method too, like this:
Private Sub Form1_Load()
DoSomeWork()
End Sub
Protected Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs)
DoSomeWork()
End Sub
Private Sub DoSomeWork()
' Put logic here that you want to do from form load and a button click
End Sub
This has the benefit of making the code cleaner, clearer and easier to maintain as you only need to change the logic in one place should you need to change the logic.
Note: Obviously, you can pass parameters to the DoSomeWork method, if need be, and change it to a Function if you need it to return something.
I am working with VB 2010 for an application which requires me to go back to a sub. After some digging, I found out GoSub is no longer supported. I tried using Goto but apparently you can't use it outside the sub the label is in. I tried calling the sub put the parameters were not known to me.
Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
I do not want to use the RunWorkerAsync because the worker will already be working. Please advise me on this matter.
It sounds like you are trying to solve a problem using procedural logic with an object-oriented tool.
If I understand you correctly, the sub is calling another section of code, and needs to return to the sub after it's finished. Make the called code itself a function or sub, and call it from the primary sub routine.
I have translated some code from C# to VB.net for the purpose of getting Folder Browser functionality. The link to the code is here.....
http://www.codeproject.com/KB/aspnet/DirectoryBrowsing.aspx
My issue is that I have not been able to correcly translate these two lines of code to VB.net.
TreeView1.TreeNodeExpanded +=new TreeNodeEventHandler(TreeView1_TreeNodeExpanded);
TreeView1.SelectedNodeChanged += new EventHandler(TreeView1_SelectedNodeChanged);
Every translator I have used has simply dropped the semicolon from the end of each line. But the editor still does not like them.
I could some help with this as it seems this effects the refresh of the selected folder in the tree view control.
I don't get to see the C drive folder unless I type the path in the text box, and the folder will still not expand.
thank you,
Use this:
AddHandler TreeView1.TreeNodeExpanded, AddressOf TreeView1_TreeNodeExpanded
AddHandler TreeView1.SelectedNodeChanged, AddressOf TreeView1_SelectedNodeChanged
Edit:
A different way to do this would be to apply it at the method level:
Protected Sub TreeView1_TreeNodeExpanded(ByVal sender as Object, ByVal e as TreeNodeEventArgs) Handles TreeView1.TreeNodeExpanded
' Some code
End Sub
Protected Sub TreeView1_SelectedNodeChanged(ByVal sender as Object, ByVal e as EventArgs) Handles TreeView1.SelectedNodeChanged
' Some code
End Sub
You should run this in debug to find out what exactly is going on. I find a lot of times when events of this nature are run in asp.net, you have a conflicting event that "resets" the controls you are attempting to change.