ios - What to do on -init, -viewdidload, -viewdidappear, -viewdiddisapper -

I realized that such questions have been asked before, most of them are for the older versions of iOS and have changed Do not give full answers to the issues from the edition.

To get the best performance, what kind of objects should be set up in these visual modes in a visual controller?

I should declare a detailed answer such as:
The int variable on the X is good because y and so on.
I will give explanations for NSString, NSInteger, UIImage, UI elements, graphics, network call, coredata calls

If we are all called together in a complete reply, then it will be useful for everyone.

What kind of things are we encouraged to get rid of?

Edit:

The answer to the bad question is good, but is not included in it and its features and views do not flawless

Question and answer left out viewdidappear and disappear

The old, uses nibs.

I do not agree with the answer, some have been changed since 2009.

Int:

Instant any objects that you will use to class . Do not add them to see them if they are subviews, after seeing this you will have to look in DDLOD.

ViewDidLoad:

At this point all the ideas have been fixed so you can make any modifications, add subviews, etc.

ViewedPaper:

What does this mean if you ever want to change the 5-second background picture, then I will start the timer here because you know that the viewer is watching the user Are there.

ViewDidDisappear:

No visual is currently being displayed - there is nothing that you do not need.

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