[fpc-devel] Creating a Cocoa Application

[Jonas Maebe]

On 06 Jan 2008, at 19:03, Felipe Monteiro de Carvalho wrote:

> I translated enougth headers to call NSApplicationLoad and
> NSRunAlertPanel, but I got stuck at the @"string" syntax. I tryed to
> just define PNSString as a generic pointer and pass a PChar to it, but
> it doesn't work, the application crashes with messages that the
> autorelease pool isn't installed:

@"string" is indeed a shorthand for a constant NSString. Compiler  
magic is required to construct these properly (similar to how you  
can't just fake a constant ansistring by using a pchar on a compiler  
which doesn't support ansistrings). E.g. @"This is the title" is  
translated into this:

	.cstring
LC3:
	.ascii "This is the title\0"
	.section __DATA, __cfstring
	.align 2
LC4:
	.long	___CFConstantStringClassReference
	.long	1992
	.long	LC3
	.long	17
	.text


Without this supportyou must create the NSString at run time from a  
regular constant string. Regarding when you need an autorelease pool  
and when not (and how to create it), see e.g. http://www.otierney.net/objective-c.html#autorelease


Jonas