PROG1385-Assignment 6 Ultimate Car Radio Solved

•        Create a new class called PioneerAM. This class will inherit from PioneerCarRadio.  o       PioneerAM behaves like PioneerCarRadio except that it operates in the AM band only! o           There is no ability to change to the FM band – they shouldn’t even display the FM band o          Do this by overriding the appropriate methods that are in the parent class or grandparent class. 

•        Create a new class called PioneerWorld. This class will inherit from PioneerAM. 

o   PioneerWorld behaves like PioneerAM 

▪  Except that the AM band range is 531 kHz to 1602 kHz

▪  And the interval between frequencies is 9 kHz, not 10 kHz

▪  So scanning up from 531 would bring you to 540, then 549, etc. Wrapping from 1602 brings you to 531. 

o   Do this by overriding the appropriate methods that are in the parent class or grandparent class. 

New/Delete and Exceptions
•        Create a new  testHarness (i.e. your main())  and put it in a file called ultimateRadio.cpp.  In this main o         Change your PioneerCarRadio variable to be a pointer

o   Give it an initial value of NULL o       Call this variable pRadio. 

•        When your program starts o      You will need to create and call a function named createRadio()  that takes a string (or char pointer … your choice) to determine which type of radio you want to start with and returns a pointer to that radio back to main() and into the pRadio pointer. 

▪  Your program will need to get this string (or char pointer) from the command line arguments of the program

▪  This means you needs to take in and parse command-line arguments

▪  This function will exist in the ultimateRadio.cpp file and when passed the string (or char pointer) will …

▪  If the program is started with the runtime switch of –car then instantiate a new PioneerCarRadio object and return it to assign it to pRadio. 

▪  If the program is started with the runtime switch of –am then instantiate a new PioneerAM object and return it to assign it to pRadio. 

▪  If the program is started with the runtime switch of –world then instantiate a new PioneerWorld object and return it to assign it to pRadio. 

▪  Otherwise, throw an exception. 

▪  Remember you will need to write this createRadio() function

o   Since it will be throwing exception(s), remember to put the call to createRadio() in a try block o           Remember that you will initially be getting this function’s parameter from a command line argument  o   In the catch clause, print an error message and quit the program o        Make sure to instantiate each radio in an off state

•        Whenever you use new, use the principles discussed in class to handle this correctly.  o      You are required to use the “new” new in this assignment o Use exception handling to detect out-of-memory situations 

Virtual Functions
•        In order to implement these 2 new children classes, you will once again need to override some methods

•        Make any overridden methods  virtual in the parent class o        Recommendations: ToggleFrequency(), ScanUp(), ScanDown(). 

•        Since we are using virtual functions, remember best practices and make all destructors virtual

Switching Radios and Quitting the Program  
•        Each specialized radio class needs to tell the user who they are … o The PioneerCarRadio already does with the Pioneer XS440 that appears in its output o Make the PioneerAM  class say   Pioneer XS440-AM

o   And the PioneerWorld class say                               Pioneer XS440-WRLD

•        Create a destructor for each new class o            In each destructor, simply print a message stating which radio is being destroyed 

▪   e.g. "Destroying Pioneer XS440-WRLD Radio" o The only message that should be seen from any destructor is the one from the actual data-type of the instance being destroyed

•        The output from PioneerCarRadio, PioneerAM and PioneerWorld is somewhat the same … except for the difference in its name (i.e. the first line of output) and the presence/absence of the FM band … o    Try to think of a clever way to implement this “radio name” idea …

o   Perhaps by adding a data member to one of the classes to hold the name … hmmm…

•        Each radio instance that is created, will run until the 'x' key is pressed within that instance o     This means that each of the “Pioneer” classes shares the same input processing

▪  As developed in Assign-05 o      Once an ‘x’ key is pressed, the radio object is destroyed in the ultimateRadio.cpp source o        And do nothing until the user presses one of the following keys

▪  c  -- to create and run a new PioneerCarRadio radio 

▪  a  -- to create and run a new PioneerAM radio 

▪  w  -- to create and run a new PioneerWorld radio 

▪  x  -  to quit the program 

▪  Note that these keystrokes will need to be captured and processed within your testHarness

(where the new radio would be created)

In Case It Makes Things Easier
•     You can create mutators and accessors for whatever private data members you need to from the AmFmRadio class

What Not To Do
        •      Don't put excessive amounts of the parent class's functionality (PioneerCarRadio) in the child classes

(PioneerAM, PioneerWorld) unnecessarily o This is duplicating functionality and code – a definite no-no