xmlvm-users

[xmlvm-users] Implementing new class in Objective-C

[Tomas V. <tom...@gm...>]

Hi,

I'm doing a proof-of-concept implementation with XMLVM for my master's
thesis.

I have a mobile application which uses a in-house framework and my goal is
to make the program cross compile with XMLVM and do the framework components
either in Objective-C or in Java then cross compiling it to Objective-C. So,
I'm wondering how you do when you implement new classes in Objective-C. I
will need this for our classes and possibly for Cocoa classes that are not
implemented.

>From what I have understood you create stubs in Java and then use XMLVM to
generate Objective-C source files from these. Then you do the implementation
of each class manually. Is this correct?

If this is the case and I would like to implement a new class in
Objective-C, would I do my skeleton in Java, generate the Objective-C code
and do the implementation in Objective-C?

Best regards,
Tomas Vestelind

ps. I think https://sites.google.com/a/xmlvm.org/documentation/home should
be on www.xmlvm.org

-- 
Quand on veut un mouton, c'est la preuve qu'on existe

Re: [xmlvm-users] Implementing new class in Objective-C

[Arno P. <ar...@pu...>]

the preferred way is to do as much as possible in Java and then 
cross-compile to Objective-C. If you already have an Objective-C class 
that you want to expose in Java, you need to create a Java stub and then 
write some "glue" code in Objective-C that bridges the Java API to the 
Objective-C API. This is necessary because of the certain differences 
between the languages. E.g., we have to use name mangling when 
cross-compiling from Java to Objective-C and the "glue" code needs to do 
a mapping from the mangled version of a name to the original version. 
Here is an example taken from 
xmlvm/src/xmlvm2objc/compat-lib/objc/org_xmlvm_iphone_UIImage.m:

+ (org_xmlvm_iphone_UIImage*) imageWithContentsOfFile___java_lang_String 
:(java_lang_String*)path
{
     return [[UIImage alloc] initWithContentsOfFile:path];
}

The new C backend (once its done), can automate some of the boilerplate 
code that currently needs to be done manually in Objective-C. Here is 
the same example from the C backend:

JAVA_OBJECT 
org_xmlvm_iphone_UIImage_imageWithContentsOfFile___java_lang_String(JAVA_OBJECT 
n1)
{
     if (!__CLASS_org_xmlvm_iphone_UIImage.classInitialized)
         __INIT_org_xmlvm_iphone_UIImage();
 
//XMLVM_BEGIN_WRAPPER[org_xmlvm_iphone_UIImage_imageWithContentsOfFile___java_lang_String]
	
     NSString *nsStr = toNSString(n1);
     UIImage *named = [UIImage imageNamed:nsStr];
	
     org_xmlvm_iphone_UIImage *toRet = __NEW_org_xmlvm_iphone_UIImage();
     toRet->org_xmlvm_iphone_UIImage.ocImage = named;
     return toRet;
     //XMLVM_END_WRAPPER
}

Only the code between the //XMLVM_* comments was written by hand; the 
rest was generated by the C backend.

Arno



On 11/30/10 1:48 AM, Tomas Vestelind wrote:
> Hi,
>
> I'm doing a proof-of-concept implementation with XMLVM for my master's
> thesis.
>
> I have a mobile application which uses a in-house framework and my goal
> is to make the program cross compile with XMLVM and do the framework
> components either in Objective-C or in Java then cross compiling it to
> Objective-C. So, I'm wondering how you do when you implement new classes
> in Objective-C. I will need this for our classes and possibly for Cocoa
> classes that are not implemented.
>
>  From what I have understood you create stubs in Java and then use XMLVM
> to generate Objective-C source files from these. Then you do the
> implementation of each class manually. Is this correct?
>
> If this is the case and I would like to implement a new class in
> Objective-C, would I do my skeleton in Java, generate the Objective-C
> code and do the implementation in Objective-C?
>
> Best regards,
> Tomas Vestelind
>
> ps. I think
> https://sites.google.com/a/xmlvm.org/documentation/home should be on
> www.xmlvm.org <http://www.xmlvm.org>
>
> --
> Quand on veut un mouton, c'est la preuve qu'on existe
>
>
>
> ------------------------------------------------------------------------------
> Increase Visibility of Your 3D Game App&  Earn a Chance To Win $500!
> Tap into the largest installed PC base&  get more eyes on your game by
> optimizing for Intel(R) Graphics Technology. Get started today with the
> Intel(R) Software Partner Program. Five $500 cash prizes are up for grabs.
> http://p.sf.net/sfu/intelisp-dev2dev
>
>
>
> _______________________________________________
> xmlvm-users mailing list
> xml...@li...
> https://lists.sourceforge.net/lists/listinfo/xmlvm-users

Re: [xmlvm-users] Implementing new class in Objective-C

[Panayotis K. <pan...@pa...>]

On Nov 30, 2010, at 8:18 PM, Arno Puder wrote:

> 
> the preferred way is to do as much as possible in Java and then 
> cross-compile to Objective-C. If you already have an Objective-C class 
> that you want to expose in Java, you need to create a Java stub and then 
> write some "glue" code in Objective-C that bridges the Java API to the 
> Objective-C API. This is necessary because of the certain differences 
> between the languages. E.g., we have to use name mangling when 
> cross-compiling from Java to Objective-C and the "glue" code needs to do 
> a mapping from the mangled version of a name to the original version. 

You can also take advantage of the "plugin" mechanism.
To see a demo of this convenient way, have a look at the directory
demo/iphome/plugins/Zip

Re: [xmlvm-users] Implementing new class in Objective-C

[Tomas V. <tom...@gm...>]

Hi,

Arno:
Yes, that's what I thought. So right now I'm trying to do a demo using only
Java and cross compiling it to Obj-C code. I'm also trying to implement
missing classes (now UITextViewDelegate) by first writing the stub in Java,
cc:ing it to Obj-C and filling in the methods.

Personally I found the C backend code much harder to understand but I
haven't done a lot of C or Obj-C coding. How exactly is supposed to be used?

Panayotis:
Thank you, that is a perfect example. I'm currently trying to implement
everything in Java but I think I will try something similar to the Zip
plugin after to evaluate the options.


If I implement classes on my own I would of course like to contribute and
upload them. What worries me is that as I haven't done any Obj-C before, I'm
currently reading about it and how it works so I'm not completely lost. When
I'm implementing a new class I'm also looking at other similar classes that
are implemented. But I can't be 100% sure that it's correct, how should I
proceed then?

Best regards,
Tomas Vestelind

On 30 November 2010 19:37, Panayotis Katsaloulis <pan...@pa...>wrote:

>
> On Nov 30, 2010, at 8:18 PM, Arno Puder wrote:
>
> >
> > the preferred way is to do as much as possible in Java and then
> > cross-compile to Objective-C. If you already have an Objective-C class
> > that you want to expose in Java, you need to create a Java stub and then
> > write some "glue" code in Objective-C that bridges the Java API to the
> > Objective-C API. This is necessary because of the certain differences
> > between the languages. E.g., we have to use name mangling when
> > cross-compiling from Java to Objective-C and the "glue" code needs to do
> > a mapping from the mangled version of a name to the original version.
>
> You can also take advantage of the "plugin" mechanism.
> To see a demo of this convenient way, have a look at the directory
> demo/iphome/plugins/Zip
>
>
>
>
> ------------------------------------------------------------------------------
> Increase Visibility of Your 3D Game App & Earn a Chance To Win $500!
> Tap into the largest installed PC base & get more eyes on your game by
> optimizing for Intel(R) Graphics Technology. Get started today with the
> Intel(R) Software Partner Program. Five $500 cash prizes are up for grabs.
> http://p.sf.net/sfu/intelisp-dev2dev
> _______________________________________________
> xmlvm-users mailing list
> xml...@li...
> https://lists.sourceforge.net/lists/listinfo/xmlvm-users
>



-- 
Quand on veut un mouton, c'est la preuve qu'on existe