You need to make your view controller the UITextField delegate, and implement the UITextField delegate method: – (BOOL)textFieldShouldReturn:(UITextField *)textField { if (textField == nameField) { [textField resignFirstResponder]; [emailField becomeFirstResponder]; } else if (textField == emailField) { // here you can define what happens // when user presses return on the email field } return YES; … Read more
NSArray *myArray = [NSArray arrayWithObjects:[NSNumber numberWithInt:1], [NSNumber numberWithInt:2], [NSNumber numberWithInt:3]]; Update for new Objective-C syntax: NSArray *myArray = @[@1, @2, @3]; Those two declarations are identical from the compiler’s perspective. if you’re just wanting to use an integer in a string for putting into a textbox or something: int myInteger = 5; NSString* myNewString = … Read more
You need to use NSStringFromCGRect which will convert the CG structs into NSString, Refer below:- NSLog(@”%@”, NSStringFromCGRect(frame)); Also below are the following other functions which can be used for NSLog CG Structs as well:- NSStringFromCGPoint NSStringFromCGSize NSStringFromCGRect NSStringFromCGAffineTransform NSStringFromUIEdgeInsets
To check for equality you can use, CGSizeEqualToSize function by Apple. CGSize firstSize = CGSizeMake(1.0,1.0); CGSize secondSize = CGSizeMake(5.0,3.0); if(CGSizeEqualToSize(firstSize, secondSize)) { //they are equal }else{ //they aren’t equal }
Simply checks for nil and if length of text length is greater than 0 – not empty if (textField.text && textField.text.length > 0) { /* not empty – do something */ } else { /* what ever */ }
If you have an existing color, you can return a new one with a specified alpha, like this: – (void)setBackgroundColor:(UIColor *)color { self.backgroundColor = [color colorWithAlphaComponent:0.3f]; }
I only use the next conditional and do not even need a category: if (!aString.length) { … } Using Objective-C theory, a message to NIL will return nil or zero, so basically you do not have to test for nil.
Checking if 2 printf() format strings are compatible is an exercise in format parsing. C, at least, has no standard run-time compare function such as: int format_cmp(const char *f1, const char *f2); // Does not exist Formats like “%d %f” and “%i %e” are obviously compatible in that both expect an int and float/double. Note: … Read more
I opened a bug regarding this. According to Apple, “Snapshots have been removed in Xcode 7. You can export existing snapshots in Xcode 7 but not create or restore them.” Hopefully they’ll restore them in a future release, but for now I recommend using git from the Source Control menu as suggested by Tim.
Sure, that works fine. Apple uses the same approach for example in the UIGestureRecognizer class. Subclasses have to import the additional UIGestureRecognizerSubclass.h file and override the methods that are declared in that file.