How to debug a non-working declare?

Targets macOS
1

Been working a while with the Chilkat lib for IMAP. Since my test application does what I want, today I integrated the code into my mail application. Now one of the declares doesn’t want to work. I can register the lib, logging into an IMAP account also works. But getting the mailboxes simply does nothing:

[code] declare function ListMailboxes lib ImapLibLocation selector “ListMailboxes:wildcardedMailbox:” _
(obj as Ptr, refname as CFStringRef, wildcard as CFStringRef) as Ptr

dim p as Ptr = ListMailboxes(self, “”, “*”)
if p <> nil then
dim theMailboxes as new MailboxesCko(p, False)
MailboxesOriginal = theMailboxes.getMailboxes
MailboxFlags = theMailboxes.getFlags
end[/code]

In the test app p is not nil. In the main app p is nil. The code uses MacOSlib. The super of the class of the code is NSObject.

How do I find out why the declare isn’t working? I can’t see a difference in the execution compared to the test app.

Mac OS 10.10. Xojo 2015r2.

2

Objective-C function calls return no error if object is nil.

Also why do you pass self here? Shouldn’t you pass a handle or object pointer?

3

self is used here because the super of the class is NSObject. At least that is what Thomas Tempelmann taught me about declares.

4

so he probably overloaded it with Operator_Convert?

Anyway, if this would return nil, the call will do nothing.

5

Is self really an instance of the same class as in your test application?

6

@Eli: yes, the codes lives in the same class in both apps. Actually, the class is the same external item.

But I had another idea: in the test app the code is executed directly. In the main app I have the usual mess of threads and timers. I dimly remember having problems with code in threads before. Will do some testing tomorrow.

7

The CkoImap class has a LastErrorText property (plus a LastResponse and a LastResponseCode). These will help you debugging.

So you could try this:

dim p as Ptr = ListMailboxes(self, "", "*") if p is nil then MsgBox self.LastErrorText else dim theMailboxes as new MailboxesCko(p, False) MailboxesOriginal = theMailboxes.getMailboxes MailboxFlags = theMailboxes.getFlags end