What the meaning of [NSBundle mainBundle] in iPhone?

Question

RootViewController *rvController = [[RootViewController alloc] initWithNibName:@"RootViewController" bundle:[NSBundle mainBundle]];

sometimes i see it use nil ,i dont know what exactly it use for?

Answer 1

Here is the exact explanation for that:

The bundle in which to search for the nib file. This method looks for the nib file in the bundle's language-specific project directories first, followed by the Resources directory. If nil, this method looks for the nib file in the main bundle.

I think [NSBundle mainBundle] doesn't do anything different than you put nil. However, if you want to do internationalization and localization, you can use them

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