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iOS Build a Blog Reader iPhone App Data Modeling Using a Custom Class

Posted by AbdelGhafour Mohie
AbdelGhafour Mohie
1,876 Points

In what cases should we use Designated & Convenience ?

Actually i have 2 questions:

1- So this app could perfectly run without the designated initialiser or the convenience constructor, ( i just tried it) So why did we use them? and if this app can run without them , are those methods ever be mandatory in any other case ?

2- Why did we save the data we grabbed from the blog in our system ? doesn't that just keep eating memory ?

2 Answers

P M
P M
7,320 Points
P M
P M
7,320 Points

  1. If you will use them (call them in your code), they are mandatory. If not - they are not. It's much cleaner to use them than to have lots of nested initialisers all over your code.

  2. If you have no data, how would you display it? Even the web page you're looking at now is saved in your computer's RAM first before it shows on the screen. Same with the data from the blog, first you grab it so you can manipulate it locally, then display it.

AbdelGhafour Mohie
AbdelGhafour Mohie
1,876 Points
AbdelGhafour Mohie
AbdelGhafour Mohie
1,876 Points

Thank You. so using them is just more of an organising thing.