The easy way to achieve a static background image with a scrolling UITableView: – (void)viewDidLoad { [super viewDidLoad]; self.parentViewController.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"background.png"]]; self.tableView.backgroundColor = [UIColor clearColor]; }
I was using a UITableViewController that implemented the NSFetchedResultsControllerDelegate protocol. When navigating to this view, and then to another my application would crash with an error message something like: Terminating app due to uncaught exception ‘NSInvalidArgumentException’, reason: ‘-[__NSCFType controllerWillChangeContent:]: unrecognized selector sent to instance I finally tracked down the problem to be that I was [...]
You can use the following code to dismiss the keyboard when you tap the background or a tableview cell. The cell selection should still work as expected. – (void)viewDidLoad { // ……. UITapGestureRecognizer *gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(backgroundTap)]; gestureRecognizer.cancelsTouchesInView = NO; [self.tableView addGestureRecognizer:gestureRecognizer]; [gestureRecognizer release]; } – (void)backgroundTap { // resign the first [...]
To set a property on your application delegate from anywhere in you code: [(SomeAppDelegate *)[[UIApplication sharedApplication] delegate] setFoobar:aFoobar]; And to read back the property: NSString *myFooBar = [(SomeAppDelegate *)[[UIApplication sharedApplication] delegate] foobar];
These two static methods are useful for returning a formatted date string from an NSDate object. The first method takes both NSDate and your format NSString. The second calls the first method and passes in a default formatting string. + (NSString *)getFormattedDateString:(NSDate *)date:(NSString *)format { NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease]; [dateFormatter setDateFormat:format]; [...]
This static method will return a properly formatted UK currency string from the value of an NSNumber object. + (NSString *)getPriceFromNumber:(NSNumber *)value { NSNumberFormatter *formatter = [[[NSNumberFormatter alloc] init] autorelease]; [formatter setNumberStyle:NSNumberFormatterCurrencyStyle]; [formatter setCurrencySymbol:@"£"]; return [formatter stringFromNumber:value]; }
Use the following CSS rule to disable, or change the highlight colour when you tap on an element in safari running on the iOS platform. #element { -webkit-tap-highlight-color:rgba(0,0,0,0); }
Example of parsing a string that represents the UNIX timestamp into an NSDate object. In this case, the property of an array of JSON encoded objects. [NSDate dateWithTimeIntervalSince1970:[[[jsonArray objectAtIndex:i] objectForKey:@"timestamp"] intValue]];
The quick and simple way to log the value of most datatypes in objective-C. NSLog(@"%d", somenumber); The other options are: %@ Object %d, %i signed int %u unsigned int %f float/double %x, %X hexadecimal int %o octal int %zu size_t %p pointer %e float/double (in scientific notation) %g float/double (as %f or %e, depending [...]