Is it possible to view the source of a mac app? - xcode

Would be usefull to see how things work but not sure on the legality of it

Most Mac apps are written using Cocoa in Objective-C; which, while it is a compiled language, means that there is a fair bit of information left over that could be used by a decompiler.
I'm not sure if there are a lot of decompilers out there that leverages this information, at least I haven't heard of any.
However, there are also another option; F-Script.
F-Script can be used to attach to an executable and explore its interfaces, while not as good as source, it can give you a pretty clear idea of how the executable is built, and how it operates.
As for the legality issue:
IANAL, but as far as I know, reverse-engineering for the purposes of compatibility is legal in many jurisdictions, and I can't imagine that decompiling an executable to look at its code is illegal, unless the specific EULA specifically prohibits it.
Edit: WRT Steam specifically, it is probably NOT written in Cocoa, but C# with some manner of .NET compatibility layer; and it's probably not a good place to start if you want to learn how to make applications for Mac OS X.

By far, the best Mac OS X disassembler I've used is Hopper available here:
http://www.hopperapp.com/
It will also convert the assembly to C pseudo code as best it can. It will generate code flow diagrams with blue lines (true blue, love it) for true and red for false paths.
It's The Mac OS reverse engineering tool. There are even Youtube videos that will show you how to use it.

If it's an open-source app, yes. Otherwise it's possible through decompilation but the output will be a real pain in the ass to look at. If you just want the protocols and the interfaces of categories and classes, have a look at class-dump.
I'm not aware of a nib decompiler.
Whether decompilation is legal: ask a lawyer. This may (and probably does) differ per jurisdiction.

Is it possible to view the source of a mac app?
Realistically, no. Sure, you might be a able to use a decompiler to get a peek, but the kind of output you'll get won't be easy to read. If you're asking this question, this route probably isn't going to be helpful to you.
Specifically interested in GUI and how the steam app for mac works
It's a good bet that it works about the same way that most other applications work. It might use custom controls to look different from a typical application that mostly uses the standard Cocoa controls. But underneath, just about any GUI application written for MacOS X will use the run loops, responder chain, and view hierarchy that Cocoa provide. The main exceptions would be applications that are built mostly using an alternate framework like OpenGL or WebKit.
Figure out what, specifically, the Steam application does that you'd like to do. Take a look at the tools that Cocoa provides to see if you can figure it out yourself; if not, ask about it here.

Related

Best Language for cross-platform screen recording and streaming?

So I'm looking to build an application that will be able to record the users screen and stream it at the same time. I would like the application to run on both Windows and OSX. I don't have a high level of programming experience in any language, just basic understanding in C, C++, JS, (funny how each class you take in college wants a different language). I'm also pretty well versed in HTML and CSS but that is kind of irrelevant for this topic.
I've been looking around and it looks like the best solution is going to be writing the core of the program in one language, and then developing the Interface side for each platform differently, using appropriate languages and bindings for the different platforms (Objective-C and Cocoa for OSX and so forth).
I'm open to all suggestions, this project doesn't have a deadline or anything, I'm really just intending it as a learning experience. I've never done anything with video capture and streaming before, so I'm looking for suggestions as to which road to go down language-wise for this project.
Thanks in advance :)
the simplest solution that comes to my mind is to use VLC.
this is obviously not a "language" but an application, but it supports screen-capture and streaming on all of your target platforms (and more).
if this is not an option (e.g. because you don't want a separate application), you could use VLC's C-api for acquiring screen capture and use whatever you like for streaming.
if you want to only rely on native functionality, i would use C/C++ for the application and write the OSX part in ObjC/ObjC++ and Cocoa.

Doing native GUI with Ruby

I'd like to develop a desktop app with Ruby. However, I'd like to have a native GUI on every platform (as opposed to a cross-platform GUI Toolkit that looks consistently awful across all platforms).
I expect to have to do different GUIs for each platform (as it's not just looks but also behaviors and idioms that are different), but I wonder what my options are? Especially wondering if there is a clean way to separate front and backend and bind the data properly?
Target Platforms are Windows (Vista & 7, XP is a Bonus), Mac OS X (Cocoa) and Linux (GTK? Qt? No idea).
The Ruby language has excellent Qt library bindings and your scripts will be cross-platform.
Two Kinds of Cross-Platform
It turns out there are two kinds of cross-platform UI toolkits.
One kind draws its own controls, and, like you said, looks equally bad on all platforms. Even worse: it looks out-of-place on all except one.
But there is another kind that just provides a harmonized interface to the native widgets. The best of example of this kind of toolkit is SWT1.. It looks, it is, approximately fully native on each platform, yet it has but a single API.
So you shouldn't simply rule-out all cross-platform toolkits, just rule out the ones that fake the native UI.
Develop the Wrapper Interface
There is a second way. If your program's interface with the user can be directed through a relatively narrow interface, you can simply develop to that interface and then implement the bottom part of it for each platform you want to support. Yes, you have to rewrite one module, but all the other modules stay exactly the same and you get native widgets. You also get the smallest possible executable without lots of bloat.
Perhaps most importantly, you don't have a complex and opaque software layer between your code and the native windowing system. You will probably save as much time debugging as you spend writing the extra module for your first port.
1. I know my Java examples won't help you much unless you are using jRuby, but SWT vs Swing is a really pure example of the right-vs-wrong (IMHO) UI toolkit divide.
The WxWidgets interface claims to use the native interface on Windows, OS X, Linux and UNIX through one API.
Coworkers who have used it in the past enjoyed it well enough, but I've not used it myself.

GUI library for elderly people?

I'm trying to develop a simple program in python (but this is not a requirement, I can switch to another language if worthwhile) and I'd like to make it very usable by elderly people, is there some GUI library already available?
Well, which OS platform are we standing in? If you are in linux or windows and using C# take a look at MonoDevelop. If in linux, I would stick with QT LAF and there's also GTK too.
Now, if I was in your position I would start making prototypes of the program and presenting them to the ederly, survey them through the process and make best of their inputs. It's not an easy task but it will do the work at the end of the process. Keep it simple and don't try to clutter up the ui design.
if your making a seperate GUI for elderly people it's probably best you make it yourself from whatever existing code/libraries you have.
Like increasing the element and text sizes, and increasing the contrast. But not too much that you make the majority feel patronised.
Most GUI libs support some kind of widgets that can be used for people that have some problem with their eyes or such. However, i don't think that there is a library that is particularly targetted to that. Hence, i would use GTK or Qt. In the end, it comes down to how you design your GUI.

Is there any cross-platform GUI Toolkit which does not follow the one source to rule them all concept?

After a long evaluation period of mainstream toolkits Qt, WxWidget, GTK i came to the conclusion that it does not make sense to religiously equalize the different platform. Now more then ever before.
In the days before Java portability meant, that platform dependent code was located in known places and should be small but not none. No write once, run everywhere marketing.
Is there any GUI tookit - experimental or commerical (even outdated or dead projects) - that is going this way. It would need to give me native widgets of course. I would like to have a look at them before i start my own toolkit
If you think this is a stupid idea tell me why (cause everybody else is doing it differently there may be a reason i don't see)
As someone who zealously believes that GUIs should be drawn with native widgets, I must say I've been very impressed with wxWidgets, although you mention that at the beginning.
As far as I know, wxWidgets uses native widgets whenever possible, and indeed it does also include platform-specific features that are neither possible nor relevant on other platforms. A good example of this is how you can use the native Mac OS X menu, while on other systems it won't do squat. There are other and better examples.
I must mention wxPython in particular, in case you either don't want to or just don't have the time to write a C++ program. wxPython astonished me when I tried it out first, and I even managed to make a stand-alone .exe file from it that worked on a fresh install of Windows 2000 without any updates or particular runtime environments.
If wxWidgets doesn't suit your needs, I wonder what would. :) Hurray for wxWidgets!
AFAIK, wxWidgets uses the platform's native widgets whenever possible.
Have a look at SWT, it tries to use the widgets of the underlying platform as much as possible.

How to decide GUI Framework for desktop application project

I am working on a new small utility desktop application but I am not really able to choose the GUI framework to use. I have worked on both JAVA,C# and C++, so language is not really a constraint. My criteria are:-
A very well designed architecture, something like QT. It's better if it follows typical C++ design methodologies.
Layout management should be easy, intuitive and not really cumbersome. I hate adjusting pixels on screen.
Its license should be open.
It should look good :)
Mentioned QT seems to comply to all your requirements. QT has "deploy everywhere" attribute, whilst Java needs no deploying at all (it depends on what is use of your utility).
Ad. 2 QT has really convenient GUI designer.
Ad. 3 LGPL. Usually it is enough.
Ad. 4 It is always matter of taste. IMO QT4 looks awesome under linux, but it's windows look'n'feel is correct at best. It's strong point is, that without additional tweaks it almost everywhere looks native.
I've been using Swing, and it works fine. NetBeans (a decent IDE by itself) even supports graphical GUI building.
It's well designed (basically
everything is done with listeners,
functions that are registered for a
certain event). It has bindings, so
you don't have to write code to set
up a value in a text field or read
it out
Layout is not perfect, but
acceptable within NetBeans. It's
WYSIWYG (almost). Look-and-feel can
be changed on the fly.
License is free. Source-code is not
available, I think.
Looks fine on Windows and Linux,
less so on OSX.
You could always try SWT. The advantages of Java with the standard L&F of supported operating systems.
Well designed. Lots of
documentation, and very easy to
develop with. (If you know Swing,
you can pick up SWT in no time.)
I believe layout managers do exist
that support SWT. I'm not positive
about this though, as I typically
don't use layout managers too much.
Uses the Eclipse Public
License. Should meet most of
your requirements.
From Wikipedia on SWT:
SWT is written in Java. To display GUI elements, the SWT implementation accesses the native GUI libraries of the operating system using JNI (Java Native Interface) in a manner that is similar to those programs written using operating system-specific APIs. Programs that call SWT are portable, but the implementation of the toolkit, despite the fact that it is written in Java, is unique for each platform.
Hope that helps you.
I'd suggest wxWidgets if you want to program in C++ or wxPython (the python language binding of wxWidgets if you know or don't mind learning Python.
Architecture is similar to QT I think.
Layout using sizers. Quite easy once you get the hang of it.
Liberal open source license.
Widgets are native on all platforms (Windows, Mac OS X, Linux).

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