NSString.m

产生两不迥频率的信号，并对两信号作复数FFT变换，找出频率为50Hz的信号对其进行能量计算(Two distant signal is not generated frequency, and two signals for complex FFT transform to identify the frequency of 50Hz signal to calculate its energy)

objective-c textfield 下拉菜单实现(objective-c textfield drop-down menu to achieve)

自定义风格的SegmentedControl，IOS编程学习源码，很好的参考资料。(A custom style SegmentedControl, learning IOS programming source code, a good reference.)

英文书Beginning Mac OS X Snow Leopard Programming的源码。(Source code of book "Beginning Mac OS X Snow Leopard Programming")

导航栏，精选ios编程学习源码，很好的参考资料。(The navigation bar, select learning IOS programming source code, a good reference.)

cocos 2d sample using simple tile operations.

二维码编码，QR码实现，Two-dimensional coding, QR code to achieve, Two-dimensional coding(Two-dimensional coding, QR code to achieve, Two-dimensional coding)

本书籍讲诉的是objective-C编程中的ARC规范，是高手的必看书籍。(This book stresses that the ARC specification of objective-C programming, is the master of the books.)

这是个图片显示的例子。帮助查看资料。资料的详细功要让或其他好源码(This is a picture display example. Help View information. For more information or to make a good power source)

iOS中自定义pagecontrol的DEMO，很适用很好(DEMO iOS custom pagecontrol, it applies very well)