menus

  • Thread starter Thread starter Guest
  • Start date Start date
G

Guest

Hi all,

I am creating an application that has menu options, with a 'Navigation' menu
that will re-direct the user to the appropriate form when clicked. I have a
Case structure in a class file for the application to access because there
are about 12 different forms to choose from. When the appropriate selection
is clicked, it will call a method in the aforementioned class file, and pass
a global variable to the method. Is the menu index based? I tried to start
the Case at:

Case = 0
show form a
Case = 1
show form b
etc.

This doesn't work. Any suggestions are appreciated.

Thanks!
 
Dave, I assume from your question that your using the same Click event
hhandler for all items in your Navigation menu, eg

this.menuItem1.Click += new System.EventHandler(this.menuItem_Click);
this.menuItem2.Click += new System.EventHandler(this.menuItem_Click);
this.menuItem3.Click += new System.EventHandler(this.menuItem_Click);

where all click events go to menuItem_Click.

If that's the case can you use the Index property of the clicked menu
to work out it's 0-bssed index in its parent menu, thus:

private void menuItem_Click(object sender, System.EventArgs e)
{
MenuItem menuItem = sender as MenuItem;
switch (menuItem.Index)
{
case 0:
//show form a
break;
case 1:
//show form b
break;

}

}
 
Jason Hales said:
Dave, I assume from your question that your using the same Click event
hhandler for all items in your Navigation menu, eg

this.menuItem1.Click += new System.EventHandler(this.menuItem_Click);
this.menuItem2.Click += new System.EventHandler(this.menuItem_Click);
this.menuItem3.Click += new System.EventHandler(this.menuItem_Click);

where all click events go to menuItem_Click.

If that's the case can you use the Index property of the clicked menu
to work out it's 0-bssed index in its parent menu, thus:

private void menuItem_Click(object sender, System.EventArgs e)
{
MenuItem menuItem = sender as MenuItem;
switch (menuItem.Index)
{
case 0:
//show form a
break;
case 1:
//show form b
break;

}

}

Jason,
Click to expand...

Thanks for the reply. I tried what you suggested, with this sub for the
click event:

Private Sub menuNavigation_FromTheGround_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
menuNavigation_FromTheGround.Click
Methods.ShowForms(g_intAction)

End Sub

The others are similar in form, just a different navigational name. I have
it set up as a Shared Sub so it can be accessed by multiple other subs.
Anyways, I attempted what you suggested, but VS didn't like it very much.
Here is what I did:

I imported these lines at the top of the class file:
Imports System.Object
Imports System.Windows.Forms.MenuItem

Here is the code I added, as per your suggestion:
{ (it didn't like any curly brace added)
ShowForms showForms = sender as ShowForms;
Switch(ShowForms.index)
{
Select Case g_intAction

Case 0 'frmFromTheGround is selected
frmFromTheGround.Show()
with 11 other case structures of similar layout

The following errors resulted:
showForms-Argument not specified for parameter 'g_intAction' of 'Public
Shared Sub ShowForms(g_intAction as integer)
sender-sender is not declared
as-Comma, ')' or a valid expression continuation expected
switch(ShowForms.index)-same as the showForms error, above.

I must admit I am new to menu navigation, with the user being re-directed to
different forms within an application. I know that I can add a line that
will say:
frma.show,
but I want to reduce the code substantially and only make changes to one
block, if needed.

Thanks for your help,

Dave
 
Hi Dave,

Jason's solution was in C-sharp, therefore it had curly brackets and
stuff. You are coding in VB.NET, so you will have to make syntactical
changes as necessary. You cannot just remove the curly brackets and
expect it to work. In other words, the Switch structure is C# specific
and when using VB.NET, you should use the Select Case structure.

Here is a VB.NET version of the code that Jason supplied (Thank you
Jason !)

---------------------------------
Private Sub menuItem_Click(ByVal sender As Object, ByVal e As
System.EventArgs)
Dim menuItem As MenuItem = sender as MenuItem
Select Case menuItem.Index
Case 0
'show form a
Exit Sub
Case 1
'show form b
Exit Sub
End Select
End Sub
---------------------------------

Note that this method is not wired up the click events of your menus
yet. This would be done by using the

"this.menuItem1.Click += new System.EventHandler(this.menuItem_Click);"
statement if this were C#. But in VB, we have two ways of doing this :

a) Either add the following after the menuItem_Click method above
"Handles MenuItem1.Click, MenuItem2.Click, MenuItem3.Click..." (Here
you should add click events for each of the menuItems that you need to
catch)

b) Use the AddHandler statement in your Sub New procedure of the form,
after InitializeComponent()

AddHandler MenuItem1.Click, AddressOf menuItem_Click
AddHandler MenuItem2.Click, AddressOf menuItem_Click
AddHandler MenuItem3.Click, AddressOf menuItem_Click
:
:
and so on for all your menuItems.

So, my suggestion is that there is no need to use a separate class for
your menu navigation. It can be easily handled within the Main form
itself, as mentioned. This is also what Jason was suggesting.

HTH,

Regards,

Cerebrus.
 
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