Relative date to now

In my current project, I needed to know if a given NSDate was today, yesterday or earlier. Simple task, I thought. Until I looked at the documentation for NSCalendar, NSDateComponents and NSDate. While these are extremely powerful, I am not proud of the code I’ve written. It should be easier.

Anyway, the code below will take a date and return a formatted version relative from today:

  • Today, 11h35
  • Yesterday, 8h27
  • January 12, 22h27

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Redirect NSLog to a file on the iPhone

If you need to debug your app when disconnected from your Mac (and from the console), redirect all your NSLog calls to a file so you can later read it.

The method below will create a file name “console.log” in the Documents folder of your application so you can later read it.

Just call this method in your program:

- (void) redirectConsoleLogToDocumentFolder
  NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, 
                                                       NSUserDomainMask, YES);
  NSString *documentsDirectory = [paths objectAtIndex:0];
  NSString *logPath = [documentsDirectory 
  freopen([logPath cStringUsingEncoding:NSASCIIStringEncoding],"a+",stderr);

The log will never be erased, so use with caution.

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Macros for Xcode

These are some of the macros I use with Xcode:

CMLog: I use this macro to replace NSLog:

#define CMLog(format, ...) NSLog(@"%s:%@", __PRETTY_FUNCTION__,[NSString stringWithFormat:format, ## __VA_ARGS__]);

When you use this macro, it outputs text to the console, including the class and method from where it was called. So, if you call this macro from the class MyAppDelegate and the method applicationDidFinishLaunching,

CMLog(@"My iPhone is an %@, v %@", [[UIDevice currentDevice] model], [[UIDevice currentDevice] systemVersion]);

you get this in the console:
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HowTo fit text inside a UIWebView

If, like me, you want to make sure your text will fit inside your UIWebView (without scrolling), you can implement the following javascript:

    <script language='javascript' type="text/javascript">
    function adjustHeight(maxHeight) {
      elem = document.getElementById("sign");
      height = elem.offsetHeight;
      current_size ='px','')/1;
      while ((current_size-- > 10) && (height > maxHeight)){ = current_size + 'px';
        height = elem.offsetHeight;

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