Microsoft Word - iOSAppReverseEngineering.docx

+(id)composeButtonItem;

@end

Then open LongPressableButtonItem.h, and see whether it implements

_sendAction:withEvent:.

@interface LongPressableButtonItem : UIBarButtonItem

{

id _longPressTarget;

SEL _longPressAction;

}

• (void)_attachGestureRecognizerToView:(id)arg1;


• (id)createViewForNavigationItem:(id)arg1;


• (id)createViewForToolbar:(id)arg1;


• (void)longPressGestureRecognized:(id)arg1;


• (void)setLongPressTarget:(id)arg1 action:(SEL)arg2;

@end

It doesn’t implement this method either, so let’s proceed to its super class. Open

UIBarButtonItem.h:

@interface UIBarButtonItem : UIBarItem <NSCoding>

......

• (void)_sendAction:(id)arg1 withEvent:(id)arg2;
  ......
  @end

UIBarButtonItem does implement this method, so it’s UIKit that we should analyze. Drag

and drop the binary into IDA, since UIKit is big in size, it takes a rather long time to be analyzed.

During waiting time, how about dropping in http://bbs.iosre.com for a chat?

After the initial analysis of UIKit, let’s go to the implementation of [UIBarButtonItem

_sendAction:withEvent:], as shown in figure 6-19.

Figure 6-19 [UIBarButtonItem _sendAction:withEvent:]

The first function to be called is objc_msgSend. Its official documentation is:

“When it encounters a method call, the compiler generates a call to one of the functions

objc_msgSend, objc_msgSend_stret, objc_msgSendSuper, or objc_msgSendSuper_stret.

Messages sent to an object’s superclass (using the super keyword) are sent using