At the moment I’m working on the user interface and the user interactions, and have already implemented the configuration files’ parser.

The new version will implement some cool features, useful for testing and working with MySQL on a single machine:

• user preferences will implement:
  • MySQL configuration file paths;
  • configurations for servers that aren’t configured in any configuration file (so you can create server instances on the fly);
  • capability to set the main window display (if you have more than one display);
  • many other little preferences like the update frequency and the alerts options;
• multi server management for pre-configured servers and instant servers;
• testing area for querying the servers;
• report area;
• user area.

So, what I need is a little help in creating a test environment on my Mac. It is very important  for me, because it means knowing how to parse the configuration files (I’ve implemented a way yet, but I don’t know if it is right). Then it will help me in understanding what’s the most efficient way to monitor the servers and so on..

I need also someone to test the application. It is very important, because there are so many versions of MySQL server community and there are infinity ways to configure it. I’d like to realize a Universal application, something that works with any configuration.

Before you say it: I don’t want to use MySQL sandbox, because I want to recreate a real working environment.

I will appreciate any help from you all =)

Thank you!

Here it is: http://www.pietrop.com/wordpress/dev-area/tutorials/manage-nscollectionview-and-nsarraycontroller-selection-using-observers/

It’s well known that a MacBook Pro has several cooling problems and because of I have a November 2007 MBP, I ask myself:

Will my MacBook Pro survive to Snow Leopard?

If you’ve ever used a MBP, you surely noticed a consistent overheating while doing heavy operations such as video conversions, math computing, 3D rendering, etc… OpenCL will improve the computation velocity using the GPU unused power; this won’t leave CPU in an idle state! So if we consider that when CPU is at its maximum activity it rises 100°C, how about GPU? How will the MBP take care about the heat?

Time ago I took a screenshot of my MBP temperatures: I was using BoincManager and the CPU was at its maximum (my MBP mounts an Intel Core 2 Duo). Stunning!

MacBook Pro 3.1 15" temperatures - CPU is at 100% usage and GPU is idle.

Some weeks ago Apple released an update of the cooling system firmware; now even if the fans begin raising their speed at low temperatures than before and with a major speed, I haven’t noticed big improvements. And if you look at the Snow Leopard tec specifications you can see that the following video cards are supported by OpenCL:

OpenCL

• NVIDIA Geforce 8600M GT, GeForce 8800 GT, GeForce 8800 GTS, Geforce 9400M, GeForce 9600M GT, GeForce GT 120, GeForce GT 130.
• ATI Radeon 4850, Radeon 4870

This means I’m able to run Snow Leopard and to use OpenCL with my video card because I have a Geforce 8600M GT mounted on my MBP, but probably I’ll get overheating problems… who knows?!

MySQL Launcher 1.3 comes with many changes inside and outside the code. I solved many problems related to the dynamic loading of the official MySQL libraries. Now, MySQL Launcher is compatible with i386 and x86_64 architectures and is indipendent from the MySQL version installed on your system.

I’ve added many features:

• display real time information about the running server;
• execute any kind of query and display the result in a dynamic table;
• coloured dolphin in the status bar, that changes colour exactly as the application icon in the dock if the server is running or is stopped;
• display a history list of all the executed queries available from the main window and in the status menu.

For more details go to MySQL Launcher 1.3 official page.

• displaying real time information about the running server;
• an option that sets the update frequency (I’m not sure I’ll implement this);
• the capability to execute queries and to display the output in a dynamic table;
• a chronological list of the executed queries;
• an improved management of memory and object releases, with an improvement in speed and stability;
• status bar icon changing color if the server is running or is stopped.

There are also other requested features, but probably I’ll implement them in the future, not now:

• the capability to hide/show the icon application in the Dock;
• a preference pane or something similar.

If you have requests or suggestions please let me know! =)

For more details go to MySQL Launcher 1.2 official page.

MySQL Launcher 1.2

Stay tuned!

• Italian version at http://www.pietrop.com/wordpress/?page_id=415
• English version at http://www.pietrop.com/wordpress/?page_id=415#english

Icon Badge

• Italian version at http://www.pietrop.com/wordpress/?page_id=404
• English version at http://www.pietrop.com/wordpress/?page_id=404#english

WebOn is a Cocoa application that gives you the capability to take trace of web page changes and to subscribe to RSS feeds.

It uses the BWToolkit to get a cool look.

More info here.

• Italian version: (http://www.pietrop.com/wordpress/?page_id=258)
  
• English version: (http://www.pietrop.com/wordpress/?page_id=258#english)

For suggestions or corrections, please add comments in the tutorial’s page.

For more details go to MySQL Launcher 1.1 official page.

MySQL Launcher 1.1

Italiano

Ecco a voi un altro estratto dal manuale Cocoa programming for Mac OS X, terza edizione, di Aaron Hillegass. La citazione riguarda il paragrafo sul messagging, ovvero quel che accade quando viene chiamato un metodo di una classe figlia di NSObject.

Come menzionato prima, un oggetto è simile a una struttura del C. NSObject dichiara una variabile d’istanza detta isa e, siccome NSObject è la radice dell’intero albero gerarchico della classe, ogni oggetto ha un puntatore isa alla struttura della classe che ha creato l’oggetto.

Figura 3.15 Ogni oggetto ha un puntatore alla sua classe

La struttura della classe include sia il nome e i tipi delle variabili d’istanza per quella classe, che l’implementazione dei metodi della classe stessa. Tale struttura ha un puntatore alla struttura della classe della superclasse.

I metodi sono indicizzati da un selettore di tipo SEL ma, nonostante SEL sia definito come char *, è più intuitivo pensare ad esso come a un intero. Il nome di ogni metodo viene quindi associato (mappato) ad un numero intero univoco (un integer). Per esempio, il nome del metodo addObject: potrebbe essere associato al numero 12, così quando utilizzerai dei metodi, userai il selettore e non la stringa @”addObject:”.

Esiste quindi una tabella, parte delle strutture dati dell’Objective-C, che mappa i nomi dei metodi ai corrispettivi selettori, come mostrato in figura 3.16.

Figura 3.16 La tabella dei selettori

Durante la compilazione, ogni volta che il compilatore riceve una chiamata a messaggio, consulta tale tabella. Ad esempio, la seguente chiamata:

[myObject addObject:yourObject];

diventa (posto che il selettore per addObject: sia 12)

objc_msgSend(myObject, 12, yourObject);

objc_msgSend() valuta il puntatore isa di myObject per arrivare alla struttura della sua classe e cerca il metodo associato al numero 12. Se non lo trova, segue il puntatore alla sua superclasse, e se anche la superclasse non ha il metodo associato al numero 12, allora continua a cercare ripercorrendo l’albero gerarchico. Se raggiunge la cima senza trovare alcun metodo, la funzione restituisce un’eccezione.

Questo è chiaramente un modo molto dinamico di maneggiare e gestire i messaggi. Le strutture delle classi possono essere modificate durante l’esecuzione utilizzando, ad esempio, la classe NSBundle, che rende rende relativamente semplice l’aggiunta di classi e metodi al programma mentre è in esecuzione. Questa potente tecnica è stata utilizzata per creare aplicazioni che possono essere estese da altri sviluppatori.

English

Here’s another extract from Cocoa programming for Mac OS X, third edition, wrote by Aaron Hillegass. Here’s an explanation about messaging between Cocoa classes.

As mentioned earlier, an object is like a C struct. NSObject declares an instance variable called isa. Because NSObject is the root of the entire class-inheritance tree, every object has an isa pointer to the class structure that created the object.

Figure 3.15 Each object has a pointer to its class

The class structure includes the names and types of the instance variables for the class, as well as the implementation of the class’s methods. The class structure has a pointer to the class structure for its superclass.

The methods are indexed by the selector. The selector is of type SEL. Although SEL is defined to be char *, it is most useful to think of it as an int. Each method name is mapped to a unique int. For example, the method name addObject: might map to the number 12. When you look up methods, you will use the selector, not the string @”addObject:”.

As part of the Objective-C data structures, a table maps the names of methods to their selectors. Figure 3.16 shows an example.

Figure 3.16 The selector table

At compile time, the compiler looks up the selectors wherever it sees a message send. Thus,

[myObject addObject:yourObject];

becomes (assuming that the selector for addObject: is 12)

objc_msgSend(myObject, 12, yourObject);

Here, objc_msgSend() looks at myObject’s isa pointer to get to its class structure and looks for the method associated with 12. If it does not find the method, it follows the pointer to the superclass. If the superclass does not have a method for 12, it continues searching up the tree. If it reaches the top of the tree without finding a method, the function throws an exception.

Clearly, this is a very dynamic way of handling messages. These class structures can be changed at runtime. In particular, using the NSBundle class makes it relatively easy to add classes and methods to your program while it is running. This very powerful techniques has been used to create applications that can be extended by other developers.

The story of Cocoa starts with a delightful bit of history. Once upon a time, two guys named Steve started a company called Apple Computer in their garage.

The company grew rapidly, so they hired an experienced executive named John Sculley to be its CEO. After a few conflicts, John Sculley moved Steve Jobs to a position in which he had no control over the company at all. Steve Jobs left to form another computer company, called NeXT Computer.

NeXT hired a small team of brilliant engineers. This small team developed a computer, an operating system, a printer, a factory, and a set of development tools. Each piece was years ahead of competing technologies, and the masses were excited and amazed. Unfortunately, the excited masses did no buy either the computer or the printer. In 1993, the factory was closed, and NeXT Computer, Inc., became NeXT Software, Inc.

The operating system and the development tools continued to sell under the name NeXTSTEP. Although the average computer user had never heard of NEXTSTEP, it was very popular with scientists, investment banks, and intelligence agencies. These were people who developed new applications every week, and they found that NeXTSTEP enabled them to implement their ideas more quickly than any other technology did.

What was this operating system? NeXT decided to use Unix as the core of NeXTSTEP, relying on the source code for BSD Unix from the University of California at Berkeley. Whi Unix? Unix crashe much less frequently than Microsoft Windows or Mac OS and came with powerful, reliable networking capabilities.

Apple has made the source code to the Unix part of Mac OS X available under the name Darwin. A community of developers continues to work to improve Darwin. You can learn more about Darwin at http://macosforge.org/.

NeXT then wrote a window server for the operating system. A windows server takes events from the user and forwards them to the applications. The application then sends drawing commands back to the windows server to update what the user sees. One of the nifty things about the NeXT window server is that the drawing code that goes to the window server is the same drawing code that would be sent to the printer. Thus, a programmer has to write the drawing code only once, and it  can the be used for display on the screen or printing. In the NeXTSTEP days, programmers were writing code that generated PostScript. Whit Mac OS X, programmers are writing code that uses the CoreGraphics framework (also known as Quartz). Quartz can composite those graphics onto the screen, send them to the printer, or generate PDF data. The Portable Document Format is an open standard created by the Adobe Corporation for vector graphics.

[...]

NeXTSTEP came with a set of libraries and tools to enable programmers to deal with the windows manager in a elegant manner. The libraries were called frameworks. In 1993, the frameworks and tools were revised and renamed OpenStep, which was itself later renamed Cocoa.

[...]

Programming with the frameworks is done in a language called Objective-C. Like C++, Objective-C is an extension to the C programming language, making it object oriented. Unlike C++, Objective-C is weakly typed and extremely powerful.
With power comes responsibility: Objective-C allows programmers to make ridiculous errors. Objective-C is a very simple addition to C, and you will find it very easy to learn.

Programmers loved OpenStep. It enabled them to experiment more easily with new ideas. In fact, Tim Berners-Lee developed the first Web browser and the first Web server on NeXTSTEP. Securities analysts could code and test new financial models much more quickly. Colleges could develop the applications that made their research possibile. I don’t know what the intelligence community was using it for, but intelligence aggencies bought thousands of copies of OpenStep. Because they were so useful, the OpenStep development tools were ported to Solaris, Windows NT, and the NeXTSTEP operating system was ported to most of the popular CPUs of the day: Intel, Motorola, Hewlett-Packard’s PA-RISC, and SPARC. (Oddly enough, OpenStep didn’t run on a Mac untile the first version of Mac OS X Server, known as Rhapsody, shipped in 1999.)

For many years, Apple Computer had been working to develop an operating system with many of the features of NeXTSTEP. This effort was knows as Copland. Project Copland gradually spun out of control, and Apple finally decided to pull the plug and buy the next version of Mac OS from another company. After surveying the existing operating systems, Apple selected NeXTSTEP. Because NeXT was small, Apple simply bought the whole company in December 1996.

Where do I fit into this story? I was writing code for NeXT computers on Wall Street until NeXT hired me to teach OpenStep programming to other developers. I was an employee at NeXT when it merged with Apple, and I taught many of the Apple engineers how to write applications for Mac OS X. No longer an Apple employee, I now teach Cocoa programming for Big Nerd Ranch, Inc.

NeXTSTEP became Mac OS X. It is Unix underneath, and you can get all the standard Unix programs, such as the Apache Web server, on Mac OS X, which is more stable than Windows and Mac OS 9. The user interface is spectacular. You, the developer, are going to love Mac OS X because Cococa will enable you to write full-featured applications in a radically more efficient and elegant manner.

I hope it will let you know what makes Mac OS X applications look so beautiful and useful.

It’s wonderful programming using Cocoa, and if you want to enter the Cocoa’s world I suggest you this good manual.