Test your basic knowledge |

iOS 5 App Development 2

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Instance methods start with a ______ and class methods start with a ______.
option-click; option-double-click
Dash - Plus sign.
A collection of collections in graph form. Can include NSArray - NSDictionary - NSNumber - NSString - NSData - and NSData.
NSData

2. Objects in an array: are the pointed to strongly or weakly?
Strongly.
Center of the frame - which is in the superview's coordinate system
A framework.
Two floats - for width and height

3. All classes should have a __________________ to be called by subclasses.
The runtime system asks the object what its class is.
Designated initializer.
Right-click on view - or even a subview like a button.
Creating objects - or finding information relative to the class. The name of the class is the first thing in the square brackets.

4. In the initializer methods of objects I create - add what line of code? Why?
self.view
NSObject
self
self = [super init] {if init is the designated initializer of the superclass}. If the superclass init routine fails - I will know to return nil from my init routine.

5. What is an example of a reason to write a getter?
Lazy instantiation.
NSSet; no - it's immutable
constant NSString
[Class respondsToSelector:@selector(aMethod)]

6. A _______ goes from the Controller to the View. A ________ goes from the view to the controller.
One; zero to many
Yes. The controller knows everything about the model.
Outlet; Action
self = [super init] {if init is the designated initializer of the superclass}. If the superclass init routine fails - I will know to return nil from my init routine.

7. Classes cannot have _________ or ___________.
internal origin and size. Use this inside a view
NO is zero; YES is anything else.
id; an object pointer
Properties; instance variables

8. The view is...

9. How about the model talking to the controller?

10. When is it OK to call drawRect: directly?
Never!
NSLog; %@; %d and other formatters
[Object isKindOfClass:[Classname class]]
NO is zero; YES is anything else.

11. The decision on what method to call is made when?
Yes. The controller knows everything about the model.
@interface JGEmailLoginEmailViewController(){ NSMutableData _receivedData; }@property (weak -nonatomic) JGAppDelegate appDelegate;@property (weak - nonatomic) IBOutlet UITextField *txtfldEmailAddress;@end
At runtime.
NSNumber. For example numberWithDouble: and doubleValue:

12. What is the iOS term for a library?
A CGPoint and and a CGSize
Wrap it in NSValue. And remember that NSValue immutable.
internal origin and size. Use this inside a view
A framework.

13. What does 'strong' mean?

14. A property is just the combination of _______.
line up the colons!
id
create a model
Getter and setter methods.

15. Why are properties good?
(1) We can validate (e.g. bounds-check) any sets done by a subclass. (2) We can lazily instantiate - so things only get created if and when they are needed.
NSObject
[[UIView alloc] initWithFrame]
Strongly.

16. All properties are initialized to _____
UIViewController.
At runtime.
Never!
zero/nil

17. What is a property list?
A collection of collections in graph form. Can include NSArray - NSDictionary - NSNumber - NSString - NSData - and NSData.
Instance method; class method.
[Class respondsToSelector:@selector(aMethod)]
No. It's fine.

18. When happens when you send a message to nil?
Cocoa Touch - Media - Core Services - Core OS
Nothing happens - and nil is returned.
option-click; option-double-click
Call setNeedsDisplay:

19. If a method starts with a dash - it's a ___________. If it starts with a plus sign - it's a ______________.
Properties; instance variables
Instance method; class method.
[Object isMemberOfClass:[Classname class]]
Dash - Plus sign.

20. What is the bounds property of a UIView?
(1) We can validate (e.g. bounds-check) any sets done by a subclass. (2) We can lazily instantiate - so things only get created if and when they are needed.
UIWindow
Yes. The controller knows everything about the model.
internal origin and size. Use this inside a view

21. What about the model and the view talking to one another?
The runtime system asks the object what its class is.
No. It's fine.
Properties; instance variables
Never!

22. Instead of 'include' statements - in Objective-C we use _______ which does ________
No. It's fine.
In the getter! This is called lazy instantiation.
Import / handle multiple inclusion.
Other MVC trios.

23. What does 'weak' mean?

24. What is used in lieu of pixels? And why?
Points - to achieve device-independence
NSSet; no - it's immutable
One; zero to many
Two floats - for width and height

25. What is the word for checking/verifying the type of an object?

26. What is the center property of a UIView?

27. The controller is always a subclass of...?
id; an object pointer
Yes. As much as it wants.
Lazy instantiation.
UIViewController.

28. There is no difference between _____ and _______ at runtime.
Right-click on view - or even a subview like a button.
Import / handle multiple inclusion.
Argument validation.
id; an object pointer

29. What is the makeup of a CGPoint?
Call setNeedsDisplay:
Two CGFloats for x and y
Getter and setter methods.
Points - to achieve device-independence

30. Show a private interface section.
[Object isMemberOfClass:[Classname class]]
Center of the frame - which is in the superview's coordinate system
@interface JGEmailLoginEmailViewController(){ NSMutableData _receivedData; }@property (weak -nonatomic) JGAppDelegate appDelegate;@property (weak - nonatomic) IBOutlet UITextField *txtfldEmailAddress;@end
Class XX = [Object class]

31. How to tell if an object is of a particular class? (Write a line of code)
NSDictionary; no - it's immutable.
A rectangular area
[Object isMemberOfClass:[Classname class]]
Argument validation.

32. What do I use for a bag of bits?
NSData
To zero; so pointers are nil.
Nothing happens - and nil is returned.
Dash - Plus sign.

33. What do I use for an unordered collection - e.g. test for membership? And is it mutable?

34. How are local variables initialized in iOS 5?
If it's in the header file - it's public. To make some private variables - you can put a private interface section at the top of an implementation file.
To zero; so pointers are nil.
A framework.
UIWindow

35. What do I use for a hash table/associative array? And is it mutable?

36. Dot notation does what?
@interface JGEmailLoginEmailViewController(){ NSMutableData _receivedData; }@property (weak -nonatomic) JGAppDelegate appDelegate;@property (weak - nonatomic) IBOutlet UITextField *txtfldEmailAddress;@end
create a model
On left side - is calling the setter - and on the right side - is calling the getter.
'Keep this in the heap until I don't point to anymore.' I won't point to it anymore if I set my pointer to nil - or if I am removed from the heap because no one points strongly to me.

37. How to see all actions - outlets - incoming/outgoing segues on a view?
Right-click on view - or even a subview like a button.
NO is zero; YES is anything else.
[Class respondsToSelector:@selector(aMethod)]
[[UIView alloc] initWithFrame]

38. Is NSString mutable or not?
Immutable. But there are many methods that take an NSString and returned a modified one. This is fast and preferable to using NSMutableString.
Points - to achieve device-independence
UIViewController.
Nothing happens - and nil is returned.

39. ______ is a pointer
[Object isMemberOfClass:[Classname class]]
The compiler adds code to count references.
self
Creating objects - or finding information relative to the class. The name of the class is the first thing in the square brackets.

40. What does the controller do?
A collection of collections in graph form. Can include NSArray - NSDictionary - NSNumber - NSString - NSData - and NSData.
Argument validation.
Other MVC trios.
Controls how the model is presented onscreen.

41. What do I use for an ordered collection of objects? And is it mutable?

42. A _______ is how a view notifies the controller of something - for example - a button press.
Action
On left side - is calling the setter - and on the right side - is calling the getter.
(1) We can validate (e.g. bounds-check) any sets done by a subclass. (2) We can lazily instantiate - so things only get created if and when they are needed.
Properties; instance variables

43. You can send a message to a...
id; an object pointer
constant NSString
An outlet.
UIViewController.

44. What is the fundamental design pattern of iOS development?
Interface; Implementation
for...in; don't change things inside the loop.
No. Use NSMutableArray - which is a subclass of NSArray.
MVC - for model-view-controller

45. What about the view talking to the controller?

46. Remember that it's cool to...
Points - to achieve device-independence
line up the colons!
1.) Ask another object to do it - e.g. with mutableCopy. 2.) Call a class method - 3.) [[Classname alloc] init];
No. Use NSMutableArray - which is a subclass of NSArray.

47. ________ implements the getter and setter. But we can always__________
MVC - for model-view-controller
@synthesize; write our own getter and/or setter.
To zero; so pointers are nil.
for...in; don't change things inside the loop.

48. Some controllers have ____________ as their views.
self
Two floats - for width and height
Other MVC trios.
NSData

49. How to tell whether an object is of a class or class that inherits from that class? (Write a line of code)
NSArray; no - it's immutable.
internal origin and size. Use this inside a view
[Object isKindOfClass:[Classname class]]
Two floats - for width and height

50. In synthesize: @synthesize foo = _foo; The __foo_ is the ____________ or also known as the ___________________.