System Variables Not global? 2 line function

[mbmonk]

I put this line of code in the Button1:OnPush event:

ui_msg_box(A_FORM_CURRENT, A_FORM_CURRENT)



when this executes I get gibberish for the A_FORM_CURRENT value. Its a mix of number and letters... clues why?

[Tom Cone Jr]

RE: System Variables Not global? 2 line function

Wierd.

With a bit of experimentation I found this combination that works just as expected:

curr_form = a_form_current
curr_db = a_db_current
ui_msg_box(curr_db,curr_form)

-- tom

[mbmonk]

RE: System Variables Not global? 2 line function

Thank you tom.

The problem was the form and the table were named the same so A5 couldnt tell which was being referenced.

Thankfully I copied and pasted your code and saw the problem so if you wouldnt have included the code you got to work. i would still be struggling with this.

Thank you kind sir.

[mbmonk]

RE: System Variables Not global? 2 line function

The above mentioned code by Tom does work and work properly.

This code does not:
curr_db = a_db_current
trace.WriteLn(curr_db)

ui_msg_box(curr_db,A_FORM_CURRENT)


A_FORM_CURRENT still spits jibberish.


Anyone one know what data type A_FORM_CURRENT is?
The System Variables help page says it returns the NAME of the current for. So I am assuming its a Character.

I still have no clue why a System Variable doesnt work in the button event. I again make an assumption that System Variables are of the Global Scope.

So either I have the data type wrong, the scope wrong, I have a fudemental misunderstanding, or its a bug.


Any help.

[AaronBBrown]

RE: System Variables Not global? 2 line function

Define "gibberish"

If you want the name of the current form, use topparent.name()

[mbmonk]

RE: System Variables Not global? 2 line function

gibberish = $$$06c2e728.TMP

[AaronBBrown]

RE: System Variables Not global? 2 line function

That occurs because you are toggling back and forth between design and view mode. When the form is opened from the control panel or with form.view(), that shouldn't occur.

What is it you are doing that requires you to know the name of the form?

[mbmonk]

RE: System Variables Not global? 2 line function

Wow. I am impressed you know that :).

I am just making a function that you call and it moves the focus to the next tab on the tabbed object.

FUNCTION NextTab AS V (tab_Object AS P )
'Description: Function simply moves to the next tab in a tabbed object

Dim page as N
page = tab_Object.tab_get()
tab_Object.tab_set(page + 1)

END FUNCTION

When i was originally writing that function I was trying to use the form name for an object reference. But I wanted it to work on any form so that is why I was trying to use the A_FROM_CURRENT variable.

I figured the function out but not being able to use the A_FROM_CURRENT was boggling my mind.

[AaronBBrown]

RE: System Variables Not global? 2 line function

The approach you just posted is the correct way to go about this. You should never depend on the *name* of a form to write code, otherwise if the form gets renamed, your code breaks. Whenever possible, pass object pointers, as you did above.

[mbmonk]

RE: System Variables Not global? 2 line function

Exactly, that is why I was trying to use the system variable, A_FORM_CURRENT, and not the explicit name of the form.

How can you findout the number of tabs a tabbed object has?

I looked through the properties and methods and failed to find anything that returns the number of tabs. I would like to do this so I could write 1 function that handles tab navigation.

'This would check to see if the user is on the last tab
'if so then they would be navigated to the first tab
'just cycling them
Dim page as N
page = tab_object.get_tab()
if( page +1 " tab_object.number_of_tabs)
tab_object.set_tab(1)
Else
tab_object.set_tab( page +1)
End If


Is it possible to add such a property to the tabbed object myself?

[AaronBBrown]

RE: System Variables Not global? 2 line function

What I'm trying to say is, there is no need to use the name of the form at all! You can you topparent.this to get a *pointer* to the form, rather than hard-coding the name. I'd have to see exactly what you are doing, but I doubt you need to use the name for anything.

Regardless, topparent.name() will return an appropriately normalized name of the form.

There is no built in method to determine the number of pages on the tab control, but this will work:

pTabControl.Tabs.Sheet.Size()

[mbmonk]

RE: System Variables Not global? 2 line function

At that time, I did not know how to get a pointer to an object. So I was trying to use :A_FORM_CURRENT:tabbed1 .

Now I know how to get pointers to objects, obj(), and I will use that from now on. Just like I did in the working function I posted.

Thanks for the topparent and tab size. That is useful.

As you can tell I am trying to learn Xbasic and it's standards. So I am just struggling through the basics and it can be frustrating at times trying to learn a new language.

[AaronBBrown]

RE: System Variables Not global? 2 line function

You do not need obj() to get a pointer to the current form, all you need is

pForm = topparent.this


To get a pointer to the tabbed object,

pTab = topparent.Tabbed1.this
or
pTab = pForm.Tabbed1.this

[AaronBBrown]

RE: System Variables Not global? 2 line function

" At that time, I did not know how to get a pointer to an
" object. So I was trying to use :A_FORM_CURRENT:tabbed1 .

A_FORM_CURRENT wouldn't work like that anyhow for several reasons. First, it would be looking for a form NAMED "A_FORM_CURRENT". To use a variable (like A_form_current) to get a pointer to a form, you need to use eval() or obj().

On top of that, A_form_current returns the literal name of the form, including spaces and special characters. To get a pointer to a form by name, you need to use the normalized (variable friendly) name of the form, which is stored in topparent.name().

This would work

pForm = eval(topparent.name()+".this")
as would
pForm = obj(topparent.name())
or
pForm = obj(a_form_current)

but these would not work
pForm = :a_form_current.this
pForm = eval(a_form_current+".this")



a_form_current works with obj() only because obj() is specifically designed to deal with the friendly form name.

[AaronBBrown]

RE: System Variables Not global? 2 line function

Incidentally, that "gibberish" stored in a_form_current is actually correct, and is the current "name" of the form. While toggling back and forth between design and view modes, the name gets turned into a temporary name.