Taking that one step further, Hive Logic has a couple great posts showing off some truly gorgeous monospaced fonts.  Personally, I’m in love with Monofur, Droid Sans Mono, Inconsolata, and Anonymous Pro.

Check out the two related posts here for a total of 11 great monospaced fonts.

Top 10 Programming Fonts

Anonymous Pro: A programming font with style

I did this for the first few, but as it took about 3.5 hours per project, it was a pain to schedule, and there was a lot of wasted time at night that my MacBook could have been rendering, except that after the project finished, I couldn’t figure out how to get iDVD to start on a second one.

I started writing an AppleScript to automate this, and then decided to just Google for one as someone surely had thought of this before me.  Turns out there is a very nice script that allows allows you to choose the iDVD projects you want to burn, and where you want to save the disc images.  Then, away iDVD goes.

Very nice script to have.  Mac OS X Hints.com

Turns out that you can quickly enable this feature by copying a few files according to this tip from Mac OS X Hints.com.

% echo “source /usr/share/tcsh/examples/rc” > ~/.tcshrc
% echo “source /usr/share/tcsh/examples/login” > ~/.login
% echo “source /usr/share/tcsh/examples/logout” > ~/.logout

As far as I know, this doesn’t affect any of your settings, but I didn’t look through these provided sample shell configuration files to make sure. All I know is that I can now TAB to auto-complete and nothing else has been broken so far.

I’ve discussed why I absolutely love Cappuccino for web development.  It’s a modern, full featured language and API that makes writing interactive and complex web applications much simpler.  Up until this point, writing the UI for a Cappuccino application has entailed a lot of “stupid” code for layouts and positioning of controls.  This is acceptable for people coming from Windows programming, Linux, and even Java for the most part.  You have to write a good chunk of code for even the most basic button to be on the window.

Atlas changes that.

For developers familiar with Apple’s own Developer Tools, Atlas is Xcode and Interface Builder combined into a web application, itself built upon Cappuccino.  You edit your CIB file, which contains your menu bar, windows, models, views and controllers.  It acts very similar to Interface Builder, in that you can simply drag from a button to a controller to set an action, or drag from a model to a view to set an outlet.  The Inspector even has most of the normal Cocoa conveniences.

Atlas is not yet available, but has been demoed in Miami.  You can head on over to the Atlas website, from the 280 North team ( who brought us 280 Slides and Cappuccino) to register on the mailing list.

Theory

From Wikipedia:

A genetic algorithm (GA) is a search technique used in computing to find exact or approximate solutions to optimization and search problems. Genetic algorithms are categorized as global search heuristics. Genetic algorithms are a particular class of evolutionary algorithms (also known as evolutionary computation) that use techniques inspired by evolutionary biology such as inheritance, mutation, selection, and crossover (also called recombination).

I even took the liberty of including my paper on my findings with this project, just because there are so many parameters to test and creating the graphs can be rather time consuming. So take a look at the paper if you would like to read up on the relationships between the number of chromosomes and the average fitness of the population at any given generation, for example.

More uses of NSOperation and NSOperationQueue for multithreading in this project.

Download

Xcode Project (3.1 or later) | Leopard Only

Genetic Algorithm | Leopard Only

Biologically Inspired Computation Series

Theory

Essentially, we are running a network that we can train to recognize data, or solve a problem. We do this by giving the network sample data, and for each set of sample data, running the network through one time. We calculate the error of this run, adjust the weight of the connections between all the neurons in the entire network, and repeat. After running through all the sample data we have adjusted the weights to ‘recognize’ the data. Then, given another set of data, the network is trained to perform the same operation, such as classification (maybe determining forged vs authentic bank notes) or just solving a mathematical equation, such as we do in this particular example.

Code

This simulator is written in Cocoa, requires Xcode 3.1 or later, and is Leopard only. Subclasses NSOperation for multithreading, and have two subclassed NSViews for a ‘Safari Downloads’ style window, just showing the progress of each running experiment, with a cancel button beside it.

Download

Xcode Project (3.1 or later) | Leopard Only

Neural Net | Leopard Only

Biologically Inspired Computation Series

Back Propagation on Wikipedia

Activation/Inhibition Cellular Automaton

This is a simulator written in Cocoa for running a series of experiments and creating Excel files with the results.  Activation/Inhibition CAs are similar to how a cell on a zebra determines if it should be white or black.  There is no overall governing authority, yet patterns arise naturally.  Intermediate example of using Cocoa classes such as open/save panels, notifications and the file manager.  Excellent for examining how to code complex mathematical formulas and summations in C code.

Hopfield Network

This is a simulator written in Cocoa to test the relationship between the number of stored patterns in a Hopfield Network and the accuracy with which they are remembered.  A very interesting exercise making use of NSOperation and NSOperationQueue for simple multithreading and general Cocoa design patterns such as using a delegate.

Back Propagation Neural Network

Another Cocoa simulator written to investigate the relationship between parameters for a network.  Given a set of data, can train the network to recognize that data.  Then from there, the network can ‘solve’ a problem.  In this simulation, there are two mathematical equations that are solved with this network.  Illustrates custom views, multithreading, and more.

Genetic Algorithms

The last Cocoa simulator in the series, written to investigate the relationship between input parameters for a given population of organisms over several generations.  Parameters include the probability of mutation in the offspring’s chromosomes, number of chromosomes per individual, how much sharing of chromosomes occurs when two individuals mate, and creating your own fitness function to quantify the ‘best fit’ individual based upon the DNA.  Multithreading and general Cocoa design patterns.

Going Further

I find this general area of computer science very interesting and would love to spend time researching and learning more about neural networks and genetic algorithms.  If you have any suggestions or comments about the code or projects in general, I’d love to hear from you, so drop me an email.

Theory

From Wikipedia:

  A Hopfield net is a form of recurrent artificial neural network invented by John Hopfield. Hopfield nets serve as content-addressable memory systems with binary threshold units. They are guaranteed to converge to a local minimum, but convergence to one of the stored patterns is not guaranteed.

Basically, you can fine tune the weights (connections between neurons) in the network so as to ‘store’ data in the network. Imagine a square area, not necessarily flat, with a few deep potholes in it. Now, we start the network anywhere on this grid, and as the network progresses, it moves towards the nearest pothole. At the bottom of this pothole is a stored pattern, which is ‘remembered’ by the network. So given a corrupt image, the network can ‘remember’ the real image as it works its way to the sinkhole.

This simulation investigates how many patterns a network can hold versus the accuracy with which the network can recall. For example, a network with only 5 neurons simply cannot accurately recall many patterns, and this simulator allows you to investigate this relationship.

There are two PDFs included with the Xcode project, a theoretical overview and a detailed implementation guide. The simulator produces comma separated value (CSV) files, which can be opened in Numbers or Excel for graphing.

Get Started Now

Of interest to Cocoa programmers, this project makes use of NSOperation and NSOperation queue for quick and efficient multithreading.

Xcode Project (3.1 or later) | Leopard Only

Hopfield Network | Leopard Only

Hopfield Network on Wikipedia

Biologically Inspired Computation Series

JSCocoa bridges Cocoa to JavascriptCore (WebKit’s JS engine). It allows you to call C code, ObjC code, use C structs, and build Javascript classes inheriting from ObjC classes.

Basically, JSCocoa allows you to use Cocoa classes and the runtime, only using Javascript. An important note for those following this blog closely, JSCocoa does not perform the same mission or tasks as the two other popular “javascript frameworks” aiming to bring Cocoa to the web today, Cappuccino and SproutCore. JSCocoa would allow a developer to write a full Cocoa application only using Javascript. I’m not really sure why anyone would do this, but it’s nice to have the capability.

JSCocoa Homepage

Version 0.5.5 includes over 60 fixes, and several key new features, including: New build tools, including:

• press
• Key-Value-Observing
• CPSplitView
• CPWebView
• CPDate
• Additional Editor Support
• Major performance gains

Full list of resolved bugs since 0.5.1.

Download the update directly: Starter, Tools.

If you’re not familiar with Cappuccino, I have an introductory article to look over.

The fact that I have had so many approach me, with almost the identical question raises a very valid point. Just where does one find the best documentation and sample code to get started in Cocoa development? With so many developers making the switch to iPhone and then the Mac (and hopefully Cappuccino for web), I think this post will only gain value as time goes on.

So I have compiled a list of extremely useful resources. If you spent enough time googling, you would certainly run across these sites yourself. However, I’m saving you something very precious: time. These vary in range of beginner programmer to advanced genius, so there is a little something for everyone. Keep in mind that as of writing this, official publications on Objective-C 2.0 are just barely in print, and anything for iPhone is still in the works, as the NDA keeping publishers from releasing books was just lifted a week ago.

• THE doc on the Cocoa language, from Apple, HTML or PDF
• http://developer.apple.com – Great place to start for tutorials, etc in general
• http://cocoablogs.com/ – List of all the top Cocoa developers blogs
• http://www.cocoadev.com/index.pl – THE Cocoa message boards
• http://forums.cocoaforge.com/index.php – Another great Cocoa forum, more advanced
• http://inexdo.com/CocoaNav – Wonderful little piece of software for viewing Cocoa headers (information on classes and heirachy)

The finale comes with “Cocoa Programming Mac OS X 3rd Edition“. It assumes very little programming knowledge and yet contains a good 80% of what you need to know when designing a full Cocoa programming. Key design concepts are explained in great detail and it is a wonderful resource.

If you have anything to add to this list, please leave a comment on this post or send me an email!

Theory

Imagine a single skin cell on a zebra. How does the cell know whether it should be white or black? Simply puts, the cell takes into account the value of the surrounding cells. If it’s surrounded by several black cells, then more than likely it should be black, right? Over time the cell keep looking at the cells around it, and the system changes. Eventually, the system will reach a pattern where it doesn’t change anymore. When this happens, the system has converged. Overall this is the basic theory behind pattern formation, on which the Activation/Inhibition Cellular Automaton is based.

This project is designed to investigate how varying parameters in the mathematical equation affects the pattern formation. For example, there is a parameter that influences how many cells away actually influence the current cell’s decision to be white or black. A larger number means that cells farther away are considered, while a smaller number means the converse. By varying a total of six parameters in the experiment, one can see the effect that these parameters have on the system.

Purpose

The Xcode project, aica, is written to perform a few different tasks. First off, you can quickly run a set of sample experiments that will produce some interesting converged systems. By interesting, I mean that the images representing the patterns are visually intriguing, as well as mathematically. AICA also allows a user to quickly run one experiment with a set of parameters, or run a larger set of experiments with different parameters from file.

In designing this application for my Biologically Inspired Computation course, I needed quantitative measurements describing what is happening in the system. These measurements are calculated once the system has converged and are not very pretty equations, involving lots of summations, logarithms and probability. I’m not going to delve into the mechanics and descriptions of these calculations, even though that was part of my report.

Design

I needed this to perform the basic tasks outlined above. In addition, I also wanted to have better statistics, so for each set of parameters ran (an experiment), I might want to run this several times and take the average of the calculated values describing the system. I classified each of these as a “trial”. So, the application structure is beginning to look something like this:

• Controller code for interacting with the interface and managing the experiments to be ran
• An experiment, which will run several trials and average the results, creating an Excel file with data
• A trial, which runs until convergence, writing image files for each step in the simulation

Feel free to look through project. There are two PDF files accompanying, containing the original project description and theory behind the simulation as well as a more technical document providing hints for writing the summations and mathematical equations as C code. This also contains some specific Cocoa programming techniques of interest to newbies, including using a NSProgressIndicator, Objective-C properties, NSNotifications, sheet programming, using NSSavePanel and NSOpenPanel, as well as creating directories and files using NSFileManager.

Get Started Now

Overall, if you have any comments or questions about the project, I’d love to hear from you. Even if you aren’t specifically interested, you should download the Application itself and give it a quick test run. Universal build, Leopard only. I also included some more sample files for systematically varying the parameters as I used in my project and used to draw conclusions about the behavior.

AICA Simulator (Leopard Only)

Source Code and Project Files

Biologically Inspired Computation Series

Cappuccino is a new web development platform that implements Cocoa for the web. The language, Objective-J is super similar to Objective-C and the Cocoa classes in AppKit and Foundation can be found in Cappuccino. For my first article on Cappuccino, read here.

Download now!

Check out this article from the Cappuccino blog for more information

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  <canvas id="example"></canvas>
  <script type="text/javascript">
     var g = new Bluff.Line('example', 400);
     g.theme_37signals();
     g.title = 'My Graph';
     g.data('Apples', [1, 2, 3, 4, 4, 3]);
     g.data('Oranges', [4, 8, 7, 9, 8, 9]);
     g.data('Watermelon', [2, 3, 1, 5, 6, 8]);
     g.data('Peaches', [9, 9, 10, 8, 7, 9]);
     g.labels = {0: '2003', 2: '2004', 4: '2005'};
     g.draw();
   </script>

Download Bluff Library

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for ( int i = 0, NSPoint p = [self updatingCell]; i < maxIterations && p.x > 0; i++, p = [self updatingCell] ) {
// Do something interesting with this NSPoint
}

I’ve used the above approach several times, letting me compact code when in loops. However, the next trick presented by Parmanoir, developer of CocoaNav, is one I never thought of and the article gives a wonderful explanation of the comma operator in C and family.

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// Log and return
if (error) return NSLog(@"MyFunction failed with error: %@", error), NO;

Still in beta, v1.5 introduces several new features including:

• Support for .pkg files
• Support for receiving demographic information from users
• Can update bundles, not restricted to just .app applications
• Minimum system version checking for users
• Garbage Collection
• Better version comparison algorithm
• DSA instead of less secure MD5
• Won’t update if app is running from a disk image

Andy has also taken the time to dramatically simplify the Sparkle site itself, and move the project over to Launchpad for easier development. Be sure to check out this new version to incorporate into your apps to gain the new features.

Sparkle Page

Sparkle on LaunchPad

For one, the SproutCore website is now back online after being Dugg a couple days ago. And not only that, there is a very good introduction to models, records (including saving and retrieving) and a brief introduction to the local database, called the Store. If you’re interested in developing more full-featured, Desktop like apps for the web, you need to check out the SproutCore framework.

Models Tutorial

SproutCore Site

My Introduction to SproutCore

Objective-J, Cappuccino, and 280Slides.com

My Introduction to Objective-J and Cappuccino

You can easily create a UITextField to handle text input. The interesting part comes into play because there is a keyboard associated with the UITextField, obviously for providing input. That keyboard can be specified what action to do when the return button is pressed, giving a way to process the text. The cool part is, it’s extremely easy for developers to use the many different types of keyboards present on the iPhone. For example, there is a numeric keyboard, the default keyboard, one for entering URLs, one for entering email addresses, and so on. Below is a quick code block, adapted from the “Hello World” example.

aTextField.borderStyle = UITextFieldBorderStyleRounded;
aTextField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
aTextField.placeholder = @”Your name”;
aTextField.keyboardType = UIKeyboardTypeEmailAddress;

Some other examples of keyboard types:

• UIKeyboardTypeDefault
• UIKeyboardTypeNamePhonePad
• UIKeyboardTypeNumberPad
• UIKeyboardTypeNumbersAndPunctuation
• UIKeyboardTypePhonePad
• UIKeyboardTypeURL

You can download a quick Automator Application that will copy the two files and place them on your Desktop, or use the steps below.

or, in the Finder, go to:

/System/Library/CoreServices/

One of the many items in that folder is the “Setup Assistant” application. Ctrl-click on that and choose “Show Package Contents”.

Now find:Contents/Resources/TransistionSection.bundle and ctrl-click on the bundle, choosing “Show Package Contents”.

“Contents/Resources/intro-sound.mp3″ is the music that goes along with “Contents/Resources/intro.mov”

You can copy those files to your Desktop and run them through some software (iMovie or Quicktime Pro) and get them in one file, and you have a finished result!

This has been verified to work with Snow Leopard, Mac OS 10.6 (modified on Aug 31, 2009)

Fast Enumeration

Cocoa now implements a foreach() type of loop, which cleans up code tremendously. Iterating over an array or dictionary is pretty common stuff and being able to condense code from:

NSEnumerator *e = [myArray objectEnumerator];
id item;
while ( item = [e nextObject] ) {
NSLog(@"%@", [item printSomething]);
}

to a more elegant:

id item;
for ( item in myArray ) {
NSlog(@"%@", [item printSomething]);
}

Properties

Properties are a wonderful addition to Cocoa and essentially eliminate writing basic accessor methods for your objects (setters and getters).

@interface Song : NSObject { 
NSString* title; 
Artist* artist; 
NSDate* dateAdded; 
} 
@property(readwrite, copy)NSString* title; 
@property(readwrite, copy)Artist* artist; 
@property(readwrite, copy)NSDate* dateAdded; 
@implementation Song @synthesize title, artist, dateAdded;

The ObjC 2.0 compiler gives you extreme flexibility with properties, beyond just the basic use of accessors here. You can specify a property to be readonly instead of readwrite, or to retain or assign instead of copy.

@dynamic title; -(NSString* )title { }

The above would require you to implement the method yourself, letting the compiler know you are handling that.

NSTreeNode

Not a feature of the ObjC language, but certainly a nice addition to help using NSTreeController. NSTreeNode is a wrapper object which aids in creating trees. Just create a NSTreeNode and add other NSTreeNode objects to the -mutableChildNodes array and you are on your way to a tree. Binding this tree to a NSTreeController is relatively simple as well. Of note, remember that if you are using NSOutlineView delegate methods, you receive a NSTreeNode object now, so you must use -representedObject on “id item”.

A further note, when using the “selection” controller key on a NSTreeController, the controller returns an array of NSTreeControllerProxyObjects. Either call -self on the NSTreeControllerProxyObject or when using bindings (binding a second NSTreeController to the “selection” of the first one) remember to use “selection” with model key path of “self”. I don’t believe this is documented anywhere, but using “self” clears up a whole world of heartache and gives you the actual NSTreeNode instead of the NSTreeControllerProxyObject.

Interface Builder

It took some getting used to, but recall that you have to drop a NSObject (blue cube) from the IB Library and set the custom class to initiate an object in IB 3. The old method of “Initiate Class” or whatever from the menu isn’t available. Also remember that IB Palettes don’t work with IB 3, you will need to find (or create) IB Plugins.

Core Animation

Recall that the -orderIn and -orderOut options in IB are for adding and removing subviews to the selected view in IB (-setWantsLayer:YES). So NSTabView will not magically transition views in and out unless you are programatically creating new tabs and such.

That was just a quick list of the headache I endured over the last few weeks adjusting to Leopard and mainly spending lots of time with trees in Cocoa.

I’d love to hear your thoughts about ObjC 2.0 additions, whether it’s garbage collection or something more minute!

What is interesting here is the little gem I found on the website in some sample code and open-source frameworks. The Bruji team released a framework allowing Cocoa developers to grab barcodes from an internal or external iSight or other firewire camera.

Download the source here.

What I’m trying to accomplish is a row of tabs, but the current selected one being a different color. There are all kinds of ways to accomplish this, but here is one developer’s beautiful solution for static pages. Just wrap each page in a different div. Example being, homepage has <div id=”home”>, the Help page has <div id=”help”> and so forth. On the links that make up the navigation, assign each link a class, such as “navigation-link”. Then in the stylesheet, just add something such as

#home .navigation-link, #help .navigation-link { //stuff to make it stand out }

That works wonders. However, in my case, I’m trying to accomplish the same thing on dynamic pages, created through a WordPress theme. I have a dirty solution written in Javascript, but I’m going to work on writing it in PHP if at all possible so that it doesn’t have that momentary lag that the page has right now. You can preview the work at http://www.macfanatic.net/testing/

Javascript Code for changing the class of a link to reflect it’s currently selected:

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<script type="text/javascript" src="mootools.js"></script>
<script type="text/javascript">
window.addEvent('domready', function() {
	var a_list = $$('#nav li a');    // Array of nav link elements
	var i = 0;
	while ( i &lt; a_list.length ) {
		if ( (window.location.pathname).search(a_list[i].getProperty('href')) != -1 ){
			//alert("Match found at location " + i +" with name " + a_list[i]);
			a_list[i].addClass('current');
		}
		i++;
	}
});
</script>

Also note that this uses the MooTools library, which you can download here.

1 week early I gave the guy the files and the site went live. Overall it was an awesome experience. Was my first time working with a client and working under a time restraint. I was given a featureset and I had to implement all that. In the end I was able to throw in a trick or two and get it done early, all of which pleased the guy to no end.

If you’re interested in taking a look at the work, you can check the site out over here. The site is for a new podcast with multiple shows, called MacLive. There is a teaser episode right now which you can listen to from the homepage. Be sure to read up a little on each episode and browse around.

NOTE: At the time of writing this, the site owner still hasn’t edited some text on a few pages or got the online store working yet. He wanted the site as it was to at least have something up and will edit the other pages as the information comes available. Just saving myself a little embarassment there.

I have a class called MBHand that contains a NSMutableArray as one of the key objects. So, on init, I need to set that array up to use. I thought I had that setup right. The error crept in with the following message:

-[NSCFArray addObject:]: mutating method sent to immutable object

Got to thinking and that leads back to my init method. I looked at my code and I had used the rather normal way of

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- (void)setArray:(NSMutableArray *)newArray {
	if ( array != newArray ) {
		[array release];
		array = [newArray copy];
	}
}

This method looked good, but I used array = [[NSMubableArray array] retain]; and it works fine. Therefore, it was in the setter method above. Yep, after looking at that, it hit me. I wasn’t making a mutable copy of the array passed it. Needs to have “array = [newArray mutableCopy]; ” and it works like a charm!

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- (void)setArray:(NSMutableArray *)newArray {
	if ( array != newArray ) {
		[array release];
		array = [newArray mutableCopy];
	}
}

Just a tip for all those newbies out there like me!

For those that aren’t comfortable using the Terminal, you won’t want to use this. However, for anyone else a little more technically inclined, you could very well use this program for its intended purpose. Basically, you have to provide a plain text file with a “.plist” extension ( I know this is reserved for preference files on Mac, but get over it – playlist is what it’s standing for here) that contains some basic info in a given order.

There is more information available in the PDF I’ve attached to this post, as it’s the same thing I had to write the program from. This program would be great for anyone interested in learning a bit more about data organization. The code is heavily documented showing how to use doubly-linked lists, red-black trees, hashing, and much more. And if you’re motivated, you could always read the program description and code one yourself, them compare with my code and executable. Sample input files are included.

Program description and prompt ( PDF )

Source Code (XCode Project)

Basically, the images in the “Hall of Fame” (that’s what the div container is called, for the stylesheet people out there) now move around a bit, so I can show a lot more articles and let the content grow more. It’s an easy way to see what I’ve been working on and I’ll try to keep it trimmed down, so you don’t have to sit and stare at the images for a whole minute to see all of the entries. It looks pretty cool and I’ve tested it in a few different Mac browsers, so I feel like I have all the bugs out and everything should run pretty smoothly. If you do encounter a bug or have a suggestion, feel free to email me or talk with me on iChat.

You can grab the code, with nice comments, here. Great start for those unsure of JavaScript. Uses arrays, element IDs, custom objects, and setInterval().

This app has been in “beta” testing for the last few months to some people that I know online. They have used it and provided useful feedback and expressed an interest in it. Now that the list of users has grown somewhat, I have taken up the courage to release it to the public. Let me start off by saying that this is a controversial piece of software if there ever was one. It will surely offend several of you for various moral reasons and because of that I don’t wish to discuss it anymore on the main page. If your interest is intrigued, and you are not easily offended or won’t take me hostage and call me dirty names, you can read more about the application, the license agreement, and download a copy with source at the link below.

Read more about Viewer here.

Read on to see some snippets of code with an explanation and download a sample project.

In this first bit, we are filtering out only keys pressed that are part of the numeric keypad.
Arrow keys fall into this category. The string is a string of keys pressed.

Now we have a char that represents the key pressed, an arrow key still

The above deals with the user hitting the up arrow key and the below deals with user hitting the down arrow key

Essentially, I set a NSTextField’s custom class to my StepperTextField. Then I set the outlet from the text field to a NSStepper I already have configured in the interface, correct with maxValue and minValue set for the NSStepper in IB. Of note, I use the keyUp: method because the keyDown: method is being captured by the field editor inside the NSTextField, so I never catch those events. This seemed like the simplest approach to me. Now when the user hits a down arrow, the number will decrement by one. An up arrow increments it by one. If the value will be over the maxValue, it gets set to 1. If it will be less than 1, it gets set to the maxValue.

Download a sample project with plenty of comments here.

The thing is I needed to bind a NSTextField to some values from an array controller. Not that big of a deal setting them up in code, but then I decided that to simplify my life, I would need to bind them with the “displayPatternValueX” option, instead of just binding to :@”value”. So, without further ado, here is a snippet of code that produces a single textfield on the window bound to my controller with a sorta label before the actual bound value. It’s almost magic!

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/* Rating */
NSTextField *ratingField = [[NSTextField alloc] initWithFrame:NSMakeRect(10+20, y_position – 20 – 50, windowSize.width-(2*(10+20)), textHeight+5)];
 
[[window contentView] addSubview:ratingField];
[ratingField setEditable:NO];
[ratingField setSelectable:NO];
[ratingField setFont:[NSFont systemFontOfSize:textHeight]];
[ratingField setTextColor:[NSColor whiteColor]];
 
[ratingField setDrawsBackground:NO];
[ratingField setBordered:NO];
[ratingField setStringValue:@"%{value}@ Bookmarks"];
[ratingField bind:@"displayPatternValue1" toObject: [parent BookmarksController] withKeyPath:@”selection.rating” options:[NSDictionary dictionaryWithObject: [NSString stringWithString:@"Rating: %{value1}@ "] forKey:@”NSDisplayPattern”]];

Just need to keep in mind that the magic code does what you can easily do in IB. Just to clarify, this is in a separate NIB and I’m essentially using File’s Owner as my binding object, except I used [parent BookmarksController] to access this. In IB I would have bound to File’s Owner with a modelKeyPath of @”BookmarksController.selection.bookmarkName” to get the same result. Tricky part was getting the NSDictionary setup using the constant @”NSDisplayPattern” to get the pattern to work.

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[ratingField bind:@"displayPatternValue1" toObject: [parent BookmarksController] withKeyPath:@"selection.rating" options:[NSDictionary dictionaryWithObject: [NSString stringWithString:@"Rating: %{value1}@ "] forKey:@"NSDisplayPattern"]];

Hope that all helps someone since I can’t find any documentation on the subject online. There’s plenty to explain it for IB, but there aren’t any examples of doing it by hand. Thought I would throw that out there.

Conceptually, the user will enter a search string in the search box, something like “Jo”. Now, you will need to find every object in your table that has “jo” in it. You get to choose the amount of control, as a programmer, you put into this. If you want to be very kind, you can add a drop-down menu that the user clicks to search for “Jo” just in the name field, for example. However, I feel that most people are comfortable enough with just filtering (ie, not full-scale searching), we will simply search every item in our object to find matches. Still with me?

For example (‘Por Exemplo’ comes to mind..) :

Imagine we are creating an address book-like app (hint-hint) and each person in our address book has four pieces of data each. Each person has a name, a screen name, an url, and an image associated with them. We certainly can’t filter the images, but we would like to search through the names, screen names, and urls. So, let’s figure out what we’re going to do.

First, you’re going to setup your interface in IB. I’m not going to take the time to go through all of this, but you drop a NSSearchField onto your window and hook up the bindings with the “predicate” option farther down the Inspector window. I have an array controller of “Person” objects, so I want to set my bindings as “PeopleController” as my source (same as the data source for my tableview), filterPredicate, and the model key as “personName” (the string that holds the name in a Person object, doesn’t really matter, but you must fill in a valid KVC value here).

I have also subclassed out the standard NSArrayController to provide filtering support. I connect my “search” IBAction to my NSSearchField, to actually implement the searching. I also like the instant filtering style, so I select the “Sends Search String Immediately” attribute in IB for my NSSearchField.

That ties up the interface stuff, now we need to actually figure out how we are going so sort. The concept behind this is we go through every object in the original array (that supplies the table) and see if it matches our search criteria. If it does match, we’ll throw it into a new array. When we’ve searched everything, we’ll return this array to the table so it can display it as the search results. When the user is done searching, we release that array and return the table back to the original array that holds all of our data. Let’s start searching!

Code for the filtering Array Controller

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- (void)search:(id)sender {
	[self setSearchString:[sender stringValue]];
	[self rearrangeObjects];
}
 
- (NSArray *)arrangeObjects:(NSArray *)objects {
 
	if ( searchString == nil || [searchString isEqualToString:@""] ) {
		newObject = nil;
		return [super arrangeObjects:objects];
	}
 
	/*
		Create array of objects that match search string.
		Also add any newly-created object unconditionally:
		(a) You’ll get an error if a newly-added object isn’t added to arrangedObjects.
		(b) The user will see newly-added objects even if they don’t match the search term.
	*/
 
	NSMutableArray* matchedObjects = [NSMutableArray arrayWithCapacity:[objects count]];
 
	// case-insensitive search
	NSString *lowerSearch = [searchString lowercaseString];
 
	NSEnumerator *oEnum = [objects objectEnumerator];
	id item;
 
	while (item = [oEnum nextObject]) {
 
		// if the item has just been created, add it unconditionally
		if (item == newObject) {
			[matchedObjects addObject:item];
			newObject = nil;
		} else {
 
			NSString *lowerName = [[item valueForKeyPath:@"personName"] lowercaseString];
			NSString *lowerScreenName = [[item valueForKeyPath:@"personScreenName"] lowercaseString];
			NSString *lowerUrl = [[item valueForKeyPath:@"personUrl"] lowercaseString];
 
			if ( lowerName != NULL && [lowerName rangeOfString:lowerSearch].location != NSNotFound) {
				[matchedObjects addObject:item];
			} else if ( lowerScreenName != NULL && [lowerScreenName rangeOfString:lowerSearch].location != NSNotFound ) {
				[matchedObjects addObject:item];
			} else if ( lowerUrl != NULL && [lowerUrl rangeOfString:lowerSearch].location != NSNotFound ) {
				[matchedObjects addObject:item];
			}
		}
	}
	return [super arrangeObjects:matchedObjects];
}

The code above goes through each object in the array and pulls out a string for the name, url, and screen name. It compares the entered search string to each of those strings, and if it matches, adds it to the array we return that has the matchedObjects. Of note here is that we check for a NULL string from the object because if we don’t, the object will show up in the results even though it shouldn’t.

I think that was enough of an intro to searching. Let me know if you would like to hear more about implementing the ‘Recent Search Items’ list, or searching by category. Comments are welcome. If you’re interested in a working XCode project with the code, let me know and I might throw one together and post it online.

UPDATE: I didn’t originally provide enough information about this controller, so here are a few links and documentation. Apple has documentation on this subject with almost the identical sample code that is published by mmalc below. You can read the documentation here.

Download mmalc’s source (pretty much what is in the documenation) here.  This is a sample project, so it’s nice to look at as well.  Of note, if you want the iTunes, Spotlight-like behavior of instant results (a true “filtering” action, vs searching), go into Interface Builder, select the NSSearchField and for it’s attributes, check the box with “Sends search string immediately”.  A nice example. Check out his website with lots of other good bindings related examples is here.

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<?php if ( !is_page() ) : ?>
	<span class="date"><?php the_time('F jS, Y') ?></span> &bull; <span class="postmetadata">Tags: <?php the_category(', ') ?>
<?php endif; ?><?php edit_post_link('Edit','<strong>|</strong> ',"); ?></span>
 
<div id="entry">
 
	<?php the_content('Read the rest of this entry;'); ?>
 
	<!– Checks to see if this is a post page. If it is, then we don't want to display the comments link. If not, we want to display it (main page basically) –>
	<?php if (!is_single() && !is_page()) : ?>
		<p><div id = “main-comments">There are <?php comments_popup_link('No Comments', '1 Comment', '% Comments'); ?> for 'lt;?php the_title(); ?>'</div></p>
	<?php endif; ?>
 
</div>

The problem I was trying to fix was simple. When you are on the main page of the site with all the posts, you want to be able to see the area under the post that displays information like “There are (some #) comments for (post name)”. You don’t need to see that when you are on the actual post’s page to read the full post and look at comments. You also don’t need to see a date and tag info for pages in WordPress, such as the new About and Downloads pages. Just of note, I have left Rapidweaver for this site. It’s on a sad note since Rapidweaver is what spawned this site almost a year ago this week. It’s been a great year and I’ll more about that later, but I’m no longer using Rapidweaver on the site.

To put it simply, the issue I was having was with the PHP if() statement, by trying to have the HTML code on the page only if it met that condition. The solution my my problem came with the realization of a colon operator in PHP that allowed me to write the above code. Just out there for anyone else that might be having issues as well.

I’m sure there are some seasoned Cocoa programmers out there wondering about my confusion over this class, but it was kinda scary. I’m very comfortable writing plain C and feel very powerful because I know what is going on and if I get a little stumped, I can always hack something homemade together. That’s not really the way it is a lot of times with Cocoa, there is so much already available you don’t have to hack it together and it would be better if you didn’t. So back to NSNumbers.

Just to get your brains working this morning, here was a preview if() statement I had in my code, just checking to see if the number that the user entered in an NSTextField was of appropriate range.

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if ( [startingValue intValue] >= 300 || startingValueInt <= 0) {
	// Do something
}

This doesn’t seem too bad at all to me. I need the value to be between 1 and 300. However, I decided to get a bit more specific with my code and created an NSArray of NSNumbers holding the upper limits to check against in each specific case. This was used to add that in the Category object itself and then you come up with the following if statement, if you will:

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// This was just a very lengthy way of using NSNumbers to make sure that the entered value was in proper range
if ( [[NSNumber numberWithInt:startingValueInt] compare: [[categories objectAtIndex: [CategoriesController selectionIndex]] categoryMaxValue]] == NSOrderedDescending || startingValueInt <= 0) {
	// Do something
}

Now granted, you could still use a regular “>=” operator here by calling the “- intValue” method on the NSNumbers I’m using. However, I thought that I would go all out and even use an NSComparisonResult as well. Just goes to show you that you can look smart and your code do nothing at all. Another snippet of code is below for those that wondered about getting all of my NSNumbers into my Category array.

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// Setup another array with just the ranges for each category — This is the max array, all mins are zero
// Note that I have setup similar arrays holding the names and urls that I’m sticking into each Category ‘c’
 
NSArray* maxes = [NSArray arrayWithObjects:[NSNumber numberWithInt:445], [NSNumber numberWithInt: 265],
	[NSNumber numberWithInt:221], [NSNumber numberWithInt:106], [NSNumber numberWithInt:69],
	[NSNumber numberWithInt:21], [NSNumber numberWithInt:229], [NSNumber numberWithInt:69],
	[NSNumber numberWithInt:322], [NSNumber numberWithInt:266], [NSNumber numberWithInt:138],
	[NSNumber numberWithInt:320], [NSNumber numberWithInt:107], [NSNumber numberWithInt:99],
	[NSNumber numberWithInt:313], nil];
 
// Now need to create the categories, using each piece to make one, and insert it into the categories array
for (NSInteger i = 0; i < [names count]; i++) {
	c = [Category new];
	[c setCategoryUrl: [urls objectAtIndex:i]];
	[c setCategoryName:[names objectAtIndex:i]];
	[c setCategoryMaxValue:[maxes objectAtIndex:i]];
	[categories insertObject: c atIndex: i];
}

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