Custom UITableViewCells

I've decided to write a blog post about the best way to create a custom UITableViewCell using a xib. I haven't been able to find a tutorial that covers all the steps, and since this is a very common thing, I'm going to outline them here.

To start, I'm going to assume you have a project set up, and you have a view controller that contains a UITableView.

First thing you are going to do is create the cell.

1) Go File > New > File... > Cocoa Touch > Objective-C class.

2) In the "Subclass of" field, type UITableViewCell. In the "Class" field, type the name of your custom cell. Click next, and make sure to include it in your target.

3) Once the class file has been added, you can add the .xib. Go File > New > File... > User Interface > View. Make sure to name the view the same as your custom cell's class name (for organization purposes).

4) In the .xib, click on the view, and delete it. Then, from the Object Library (on the bottom right), drag a UITableViewCell onto the canvas.

5) Click on the cell in the document tree, then in the Identity Inspector (top right), type your custom cell's class name in the class field. It should autocomplete to the name.

6) In the .xib, click on "File's Owner". In the Identity Inspector, set the class to be your View Controller that contains the UITableView.

7) Now, In Assistant Editor mode, switch the second view to your ViewController.m class. It should be located under Automatic in the file tree. If you don't see it there, try clicking on "File's Owner" (the yellow cube on the left), and try again.

8) Connect the UITableViewCell in the .xib to your viewController class as an IBOutlet (control+drag from the cell to your .m file). Make sure to also import your CustomCell.h in ViewController.m.

9) Customize the UITableViewCell with UILabels, UIImageViews, etc, and make sure to connect everything to CustomCell.h, not the View Controller class. Make sure to add a custom identifier in the Identifier field in the Attributes Inspector. Also, make sure to name your views uniquely. If you were to name your UIImageView "imageView", the results are unexpected since UITableViewCell already has this property.

10) Now, we're going to make a UINib property to hold on to the nib so that we don't have to load it for every cell.

11) Now we're going to implement the two required UITableViewDataSource methods. They should look like this.

Run your app, and you should get something similar to the image below:

Sneak Peek at my new Music app

I'm working on a new music app that runs on iOS 7. Here's a few sneak peek screenshots of the app. 

FacePic now in the App Store!

The premise of the app is combining pictures from the back and front cameras on your device to create a single image, which can be shared on multiple social networks.

The app has a very simple interface, and responds quite quickly. Look for it in the App Store here.

AirBoard 2.0 Update

I've completed the 2.0 version of AirBoard. Key features include a new UI, more logic for the second screen display, and support for creating brackets. It's available in the AppStore right now: FULL or FREE.

The bracket creator works by setting up matches, and only advancing the tournament once all the matches have been completed. As you go through each match, completing it, the second screen scrolls to the next unplayed match. Eliminated contestants are stored at the bottom of the tableview.

Here's some screenshots of the app in action:

AirBoard update coming soon

I've got an update for my scoreboard app AirBoard coming out soon. This new version supports better rankings, and the ability to turn a leader board into a single elimination bracket. I'm currently working on updating the assets, and once that's done I'll be submitting.

Hundreds - Next Riddle (59)

From my sources online, I determined that this riddle was a Vigenère cipher. Vigenère ciphers are similar to Caesar ciphers, except instead of the contacts 3 character shift, it has a shift that is based on a keyword. The keyword is repeated until it is the same length as the text to encode.  i.e. If LEMON was the keyword, you would repeat it like so

LEMONLEMONLEMONLEMON

for a message like

THISISASECRETMESSAGE

Then, you take the location of each letter in the alphabet and add them together to get the new letter (it's explained more complexly on wikipedia, but this is what it boils down to). This would produce the following secret message:

ELUGVDEESPCIFARDWMUR

Thus, to decode one of these, you simply need a keyword, and subtract the keyword's letters from the encoded message's. This is the ruby script I wrote to do this:

file = File.new("vigenere.txt", "r")

cypher = file.gets

file.close

$key = {}

keyword = ARGV[0]

$letterArray = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"]

string = ""

count = 0

cypher.each_byte { |i|

   if(i.chr == " ")

      string = string + " "

   else

      keywordLetter = keyword.split('')[count%keyword.length]

      offset = $letterArray.index(keywordLetter)

      index = $letterArray.index(i.chr)

      string = string + $letterArray[(index-offset)%26]

      count+=1

   end

}

puts "\n"+string+"\n\n"

The script takes a single argument, which is the keyword, and tries to decode the message. With that taken care of, all that was left was to guess the keyword. Judging by the previous messages, the keyword had something to do with a harp or a chord or something. I tried pretty much everything I could think of, and then tried RADIUS after looking at the cipher's achievements page. The secret message:

Being part of a bad riddle that nobody cares about.

Hundreds - Next Riddle (45)

This riddle looked more like the third riddle, where letter substitution was necessary. With my handy script, I began substituting letters for short words until they made sense. Pretty soon the solution popped out: "What do persistence and a golden harp have in common". Looks like the riddles are related somehow...

Hundreds - Next Riddle (31)

The next riddle wasn't too difficult. I simply went through all the letters one by one and filtered them into columns. Turns out 4 columns is the magic number. Reading down the columns revealed the answer.

Hundreds

Hundreds is a neat new game for iOS where you touch floating circles in an effort to bring their total up to 100. throughout the gameplay, random messages will appear on the screen. These messages are riddles and cyphers which you're expected to solve for the prize of achievements in Game Center. The first one is the only one that's immediately readable: "A mouse has one snout but a hand has five". After touching the screen with 5 fingers, the first riddle was solved. Easy enough. The rest of them, however, aren't even readable.

The second riddle mixed up the letters in each word, so each word had to be unscrambled. There were a few 9 letter words which took a while, but it was eventually solved. "Persistence without patience is a golden harp missing its chord". So these are probably going to require a bit of patience from here on out.

The third riddle (the furthest I've gotten so far) looked like a cypher. Letters looked grouped together alright, but the proper letters were not contained in each word. Being the programmer that I am, I set off  writing a script to help me.

I started off with two arrays of letters; one for the keys and one for the values. As I made a guess at a letter key pair, I would remove them from their respective lists, and then randomize the rest of the pairings every second, printing the potential sentence to the screen.

As you can see, this wasn't going anywhere very fast. But, subbing x for a, o for r, and l for o got me the first four words. Slowly over time, I kept making letter substitutions that seemed logical. The script started to become quite useful in seeing the currently deciphered letters, and possibilities for other letters. Eventually, I reached the end:

No idea what it means, but it works. Only when I went to input the letters into the game did I realize that the cypher was simply the current letter plus 3. So the script was kind of overkill. But it worked!

Below is the next riddle. I will make another post when I solve that one, but it might take me a bit longer...

Here's the ruby script I wrote quickly. Feel free to use it to make or break cyphers.


file = File.new("cypher.txt", "r")
cypher = file.gets
file.close

$key = {}

def randomizeKey()
  keyLetters = ["d","g","h","n","s","t""v","w","y"]
  letters = ["b","j","g","k","q","v","w","y","z"]
 
  $key["x"] = "a"
  $key["k"] = "n"
  $key["q"] = "t"
  $key["e"] = "h"
  $key["b"] = "e"
  $key["o"] = "r"
  $key["l"] = "o"
  $key["f"] = "i"
  $key["c"] = "f"
  $key["r"] = "u"
  $key["z"] = "c"
  $key["m"] = "p"
  $key["p"] = "s"
  $key["i"] = "l"
  $key["j"] = "m"
  $key["u"] = "x"
  $key["a"] = "d"
  $key[""] = ""
 
  while(letters.length > 0)
    keyIndex = rand(keyLetters.length)
    valueIndex = rand(letters.length)
    keyLetter = keyLetters[keyIndex]
    valueLetter = letters[valueIndex]

    $key[keyLetter] = valueLetter

    keyLetters.delete_at(keyIndex)
    letters.delete_at(valueIndex)
  end

end

randomizeKey()

while
  string = ""
  cypher.each_byte { |i|
    if(i.chr == " ")
      string = string + " "
    else
      string = string + $key[i.chr]
    end
  }
  puts string
  randomizeKey()
  sleep(1)
end