Visual Programming MCQs with Answers
Practice important Visual Programming MCQs with answers and explanations.
Chapter: 41
Q741:
How do you create a new Possession instance with specific values for its properties?
A. Possession *p = [[Possession alloc] initWithPossessionName:name valueInDollars:value serialNumber:snumber];
B. Possession *p = [[Possession alloc] init]; [p setPossessionName:name]; [p setValueInDollars:value]; [p setSerialNumber:snumber];
C. Possession *p = [[Possession alloc] initWithName:name value:value serialNumber:snumber];
D. Possession *p = [[Possession alloc] initWithName:name value:value serialNumber:snumber];
Correct Answer:
A
Chapter: 41
Q742:
How does Objective-C handle dynamically typed objects?
A. Uses runtime type checking to handle unknown methods
B. Uses a static type system to manage all objects
C. Automatically converts objects to the correct type during compilation
D. Uses typecasting to manage object types
Correct Answer:
A
Chapter: 41
Q743:
How do you define a property with a specific memory management policy in Objective-C?
A. @property (nonatomic, strong) NSString *propertyName;
B. @property (atomic, weak) NSString *propertyName;
C. @property (nonatomic, copy) NSString *propertyName;
D. @property (atomic, retain) NSString *propertyName;
Correct Answer:
C
Chapter: 41
Q744:
What does @synthesize do in Objective-C?
A. Automatically generates getter and setter methods for properties
B. Defines the initial value of properties
C. Creates a class method for the properties
D. Implements default values for properties
Correct Answer:
A
Chapter: 41
Q745:
What is the function of the initWithPossessionName:valueInDollars:serialNumber: initializer method?
A. Initializes a Possession object with given parameters and returns it
B. Allocates memory for the Possession object without initializing it
C. Creates a new instance of Possession without setting its properties
D. Allocates and initializes a Possession object with default values
Correct Answer:
A
Chapter: 41
Q746:
What is the result of calling [array addObject:[NSNull null]] on an NSArray?
A. Throws an exception
B. Adds a nil value to the array
C. Adds a placeholder object to the array
D. Appends a new object to the array
Correct Answer:
A
Chapter: 41
Q747:
How do you override a method in Objective-C?
A. Use the - symbol followed by the method name and implementation
B. Use the + symbol followed by the method name and implementation
C. Define a new method with the same name in the subclass
D. Use the override keyword followed by the method name and implementation
Correct Answer:
C
Chapter: 41
Q748:
How do you log a formatted string with variables in Objective-C?
A. NSLog(@"Format: %@", variable);
B. NSLog(@"%@ %d", format, variable);
C. NSLog(@"Format: %d", variable);
D. NSLog(@"%@ - %@", variable1, variable2);
Correct Answer:
A
Chapter: 41
Q749:
What does @interface do in Objective-C?
A. Declares the public interface of a class
B. Defines the private implementation details of a class
C. Sets up the memory management for a class
D. Specifies the class methods available to other classes
Correct Answer:
A
Chapter: 42
Q750:
What is the purpose of the autorelease method in Objective-C?
A. To manually manage the memory of an object
B. To add an object to the autorelease pool and release it later
C. To initialize an object with default values
D. To directly release an object immediately
Correct Answer:
B
Chapter: 42
Q751:
What does the dealloc method do in Objective-C?
A. Initializes an object
B. Sets the retain count of an object
C. Releases the object's retained references and cleans up
D. Creates a new instance of an object
Correct Answer:
C
Chapter: 42
Q752:
What is the correct way to implement a description method that autoreleases the string object?
A. return [descriptionString autorelease];
B. return [[NSString alloc] initWithFormat:@"..."];
C. return [NSString stringWithFormat:@"..."];
D. return [descriptionString release];
Correct Answer:
A
Chapter: 42
Q753:
How do you correctly release an object that you no longer need?
A. Call [object release]
B. Call [object retain]
C. Call [object autorelease]
D. Do nothing
Correct Answer:
A
Chapter: 42
Q754:
What is the purpose of the retain method in Objective-C?
A. To create a new instance of an object
B. To increase the reference count of an object
C. To decrease the reference count of an object
D. To initialize an object with default values
Correct Answer:
B
Chapter: 42
Q755:
How do you handle memory management when returning an object from a method?
A. Always retain the object
B. Always autorelease the object
C. Release the object before returning it
D. Use autorelease if you do not want to take ownership
Correct Answer:
D
Chapter: 42
Q756:
What is the purpose of the @interface keyword in Objective-C?
A. Declares the public interface of a class
B. Defines the private implementation details of a class
C. Specifies the class methods available to other classes
D. Initializes an object and sets its properties
Correct Answer:
A
Chapter: 42
Q757:
What is the purpose of the @property keyword in Objective-C?
A. Declares an instance variable
B. Automatically generates getter and setter methods
C. Creates a class method for the property
D. Defines a static variable
Correct Answer:
B
Chapter: 42
Q758:
What does the iboutlet keyword signify in an Objective-C class?
A. It designates a property that can be connected to a user interface element in Interface Builder
B. It specifies a method that will be triggered by a user interface element
C. It declares a private method only accessible within the class
D. It initializes the user interface elements
Correct Answer:
A
Chapter: 42
Q759:
How do you connect a user interface element to a property in Interface Builder?
A. Control-drag from the interface element to the code file
B. Directly type the connection name in the code file
C. Use the connect method in the code file
D. Create a manual reference in the code file
Correct Answer:
A
Chapter: 42
Q760:
How is the showQuestion method implemented to handle the case when the last question is reached?
A. It resets currentQuestionIndex to zero and displays the first question
B. It logs an error and exits the application
C. It hides the question and displays a message
D. It loops through the questions and displays a random question
Correct Answer:
A