ContextMenu with different callers

[ultraman]

Hi there !

 

I'm totally new to VB.NET, but I works with VB6 for a few years now. So there's a lot of adjustment to do ;-)

 

My first question concerns the use of a single ContextMenu for differents controls. How can I retreive the name of the control that called the popup ? I tryed with the System.Object or the System.EventArgs passed as argument in the MyMenu_Click() event, but I can't make it work ?

 

I could declare a flag variable that would be set before the ContextMenu.Show method is called, so I can now who was the caler, but there must be an easier way ?

 

Thanx in advance !

 

Ultraman

[divil]

There doesn't appear to be a way to do this using the arguments passed to the Popup event of the context menu, so I guess you'll have to set a flag.

 

I guess MS didn't think of people wanting to use the same context menu on different controls.

 

I guess on some controls, you could check their .Focused property and that might be a way to tell if the user just clicked on them.

[ultraman]

Ok, thanx a lot Divil !

 

I used the flag for a test and it works just fine, I think I'll use this solution.

 

 

 

 

 

 

 

 

Ultraman

[Libertarian]

Sorry to resurrect an old thread, but I found it in searching for solutions to the same problem.

 

There really are instances where multiple callers to a context menu is convenient � for example, if you have a list of customer names and you want to right-click a node to perform context-sensitive operations on the data in that particular node.

 

The ContextMenu class has a method called "SourceControl" that identifies the control that launched the context menu. You can then use the object that SourceControl returns to respond to the appropriate caller, something like this:

 

txtPath.Text = DirectCast(cxtMenu.SourceControl, TreeNode).FullPath

[mhsueh001]

Question Regarding Libertarian's Method

 

I followed your example and must use sender.parent.sourcecontrol to get this to work. However I must turn Option Strict Off.

 

Is there any way to use the same context menu for multiple controls and leave option strict on?

[Volte]

If you use DirectCast to cast Sender.Parent to a ContextMenu object, it should work.

[mhsueh001]

Hi Voltface

 

Thanks for the help, but it still doesn't seem to work. I have to turn Option Strict Off. If I leave it on it says that It can't do late binding with option strict on.

 

I was using Ctype, is DirectCast better?

 

Oh, I did try DirectCast, but Sender.Parent is still underlined in blue with that error of last binding not allowed with option strict on.

 

I'm attaching the context menu to a label which is an e-mail address. If the label is right clicked, it takes the mouse click event and calls ContactEmailClickHandler.

 

So I've got this line in a sub after displaying the label:

 

AddHandler lblEmail.MouseUp, AddressOf ContactEmailClickHandler

 

    Public Sub ContactEmailClickHandler(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs)

        If e.Button = MouseButtons.Left Then

            'Sends the email address to the email system

            MessageBox.Show("You have clicked the Email " & CType(ContEmails.Item(CType(CType(sender, System.Windows.Forms.Label).Tag, Integer)).ContactEmailKey, String))

        ElseIf e.Button = MouseButtons.Right Then

            'Display a context menu

            Dim cMenu As ContextMenu

            Dim Menus(2) As MenuItem

            Dim intKey As Integer



            Menus(0) = New MenuItem("&New", AddressOf AddNewEmail)

            Menus(1) = New MenuItem("&Edit", AddressOf EditEmail)

            Menus(2) = New MenuItem("&Delete", AddressOf DeleteEmail)



            cMenu = New ContextMenu(Menus)

            cMenu.Show(CType(sender, Label), New Point(e.X, e.Y))



        End If

    End Sub







Private Sub AddNewEmail(ByVal Sender As System.Object, ByVal e As System.EventArgs)

        Dim l As Label

        l = DirectCast(Sender.Parent, ContextMenu).SourceControl





'***** I STILL GET Sender.Parent underlined saying option strict must be off *****

    End Sub

[/Code]

Edited October 3, 2003 by mhsueh001

[divil]

You're casting the wrong thing. You want to cast sender, not sender.Parent.

[mhsueh001]

To: divil

 

Hi Divil,

 

That doesn't work!

 

Sender is of type MenuItem

Sender.Parent is of type ContextMenu

Sender.Parent.SourceControl is the label that has the information that I want.

 

The label has the .text property which contains the e-mail address. It also has a .tag property that stores the Primary key of the SQL table.

 

So if

Sender = Edit, I want to be able to grab the Sender.Parent.SourceControl.Tag so I can edit the appropriate item in the email table using the primary key.

Sender = Delete, I can grab the Sender.Parent.SourceControl.Tag and delete the item using the primary key.

 

Maybe my coding is wrong. Like I said the only way I can get it to run is by turning Option Strict Off. Any help is much appreciated.

 

 

:confused:

[dynamic_sysop]

try changing this bit slightly...

Private Sub AddNewEmail(ByVal Sender As System.Object, ByVal e As System.EventArgs)

Dim l As Label

l = DirectCast(Sender.Parent, ContextMenu).SourceControl

to something like this...

Private Sub AddNewEmail(ByVal Sender As System.Object, ByVal e As System.EventArgs)
Dim mnu As MenuItem = DirectCast(Sender,MenuItem)

Dim l As Label = DirectCast(mnu.Parent.SourceControl,Label)

hope it helps.

[mhsueh001]

Re: dynamic_sysop

 

Hi, that didn't exactly solve the problem either, but you got me on the right track and I got it to work! Thanks. :D

 

From your suggestion:

This line works, and it casts sender to a menu item.

The parent

Dim mnu As MenuItem = DirectCast(Sender,MenuItem)

 

However, this line has mnu.Parent.SourceControl underlined saying that SourceControl is not a member of 'System.Windows.Forms.Menu'

Dim l As Label = DirectCast(mnu.Parent.SourceControl,Label)

 

 

So for those of you referencing this thread in the future. I needed to do this and I could keep option strict on:

 

'This line casts as a Menu Item

Dim mnu As MenuItem = DirectCast(Sender,MenuItem)

 

'This casts to a Context Menu.

Dim cMnu As ContextMenu = DirectCast(mnu.Parent, ContextMenu)

 

'This casts to the original label!

Dim l As Label = DirectCast(cMnu.SourceControl, Label)

 

Thanks to all those that responded!!