??????????????? NSURLConnection ??????URL request?? AFNetworking????????????????????????tip????????е?networking???????

??????????????????HTTP caching?? NSURLCache?? NSURLConnection???????????????????????()

????????????????????????HTTP Request??????????????NSCache??

????NSCache??NSDictionary???????????????????????????????????????????? Mattt Thompson??????????????????￡?:http://nshipster.com/nscache/

??????????HTTP????????????Google????? best-practices document on HTTP caching??

????11. ??????????

??????iOS?п????к???????????????????????????????????????С??????uozhe??????CALayer?? CoreGraphics????OpenGL?????????

????????????????????????в????????????????????????Apple UIKit team?е???Andy Matuschak?????????????graphic??????????????????

????????????????????????????????Щ???????????iOS????????????????????????????????????????????????????????????????????????app??bundle???棬????????????? – ??????????С?????????????: ????????Щ??????????????????????????(???簴?)????????????

?????????????????ζ???????????????????????????????????????鯔??????????????????????????????????????????????Ч???????????????Щ????仯??????????????bundle??С?????????

?????????????????????????????????????????????bundle?????????С??

????12. ??????澯??

????????????????iOS??????????????app?????????????????????:

??????????app???????澯?棬????????????????????檔?????????????棬??object???????Щ???????????objects??strong references.

????????????UIKit??????????????澯??????:

??????app delegate?????`applicationDidReceiveMemoryWarning:` ?????

??????????????UIViewController??????(subclass)?и???`didReceiveMemoryWarning`

??????????? UIApplicationDidReceiveMemoryWarningNotification ????

???????????????????????????κβ???????????á?

???????磬UIViewController??????????????Щ???????view?? ?????Щ?????????????????????????Щ????????????????????????app?????????????????????????

????????????澯??????????????????????????app???????????

????????????????????????????object??????????????????????檔???????????????????е????????????????????

????13. ???????????

 ?????Щobjects????????????????NSDateFormatter??NSCalendar??????????????????????????????????JSON????XML?н????????

?????????????????????????????????????????????????????????class?????????????????????

???????????????????????????????????app?????????????????У??????(singleton)???????

??????????????????????????????????????date formatter. ????ε??????????????μ?????????????????????????????????
 
// in your .h or inside a class extension
@property (nonatomic?? strong) NSDateFormatter *formatter;
 
// inside the implementation (.m)
// When you need?? just use self.formatter
- (NSDateFormatter *)formatter {
    if (! _formatter) {
        _formatter = [[NSDateFormatter alloc] init];
        _formatter.dateFormat = @"EEE MMM dd HH:mm:ss Z yyyy"; // twitter date format
    }
    return _formatter;
}