iOS后向兼容：如何发现过期接口

来源：未知责任编辑：责任编辑发表时间:2014-01-20 07:51　点击:次

以4.3以下兼容性为例，在项目预编译头文件（xx.pch）中加入如下代码：

 #import <Availability.h> 
#define __AVAILABILITY_INTERNAL__IPHONE_3_2 __AVAILABILITY_INTERNAL_DEPRECATED 
#define __AVAILABILITY_INTERNAL__IPHONE_4_0 __AVAILABILITY_INTERNAL_DEPRECATED 
#define __AVAILABILITY_INTERNAL__IPHONE_4_1 __AVAILABILITY_INTERNAL_DEPRECATED 
#define __AVAILABILITY_INTERNAL__IPHONE_4_2 __AVAILABILITY_INTERNAL_DEPRECATED 
#define __AVAILABILITY_INTERNAL__IPHONE_4_3 __AVAILABILITY_INTERNAL_DEPRECATED 

#import <Availability.h>
#define __AVAILABILITY_INTERNAL__IPHONE_3_2 __AVAILABILITY_INTERNAL_DEPRECATED
#define __AVAILABILITY_INTERNAL__IPHONE_4_0 __AVAILABILITY_INTERNAL_DEPRECATED
#define __AVAILABILITY_INTERNAL__IPHONE_4_1 __AVAILABILITY_INTERNAL_DEPRECATED
#define __AVAILABILITY_INTERNAL__IPHONE_4_2 __AVAILABILITY_INTERNAL_DEPRECATED
#define __AVAILABILITY_INTERNAL__IPHONE_4_3 __AVAILABILITY_INTERNAL_DEPRECATED

然后，编译程序，在warning中会列出不再支持的方法，逐个检查，在可能引起程序crash的地方，加入 if ( [xx respondToSelector:(deprecatedMethod)] ) { ... } 判断。

也可以加入如下代码将warning变成error：

 #import <Availability.h> 
#define __AVAILABILITY_INTERNAL__IPHONE_3_2 __AVAILABILITY_INTERNAL_UNAVAILABLE 
#define __AVAILABILITY_INTERNAL__IPHONE_4_0 __AVAILABILITY_INTERNAL_UNAVAILABLE 
#define __AVAILABILITY_INTERNAL__IPHONE_4_1 __AVAILABILITY_INTERNAL_UNAVAILABLE 
#define __AVAILABILITY_INTERNAL__IPHONE_4_2 __AVAILABILITY_INTERNAL_UNAVAILABLE 
#define __AVAILABILITY_INTERNAL__IPHONE_4_3 __AVAILABILITY_INTERNAL_UNAVAILABLE 

#import <Availability.h>
#define __AVAILABILITY_INTERNAL__IPHONE_3_2 __AVAILABILITY_INTERNAL_UNAVAILABLE
#define __AVAILABILITY_INTERNAL__IPHONE_4_0 __AVAILABILITY_INTERNAL_UNAVAILABLE
#define __AVAILABILITY_INTERNAL__IPHONE_4_1 __AVAILABILITY_INTERNAL_UNAVAILABLE
#define __AVAILABILITY_INTERNAL__IPHONE_4_2 __AVAILABILITY_INTERNAL_UNAVAILABLE
#define __AVAILABILITY_INTERNAL__IPHONE_4_3 __AVAILABILITY_INTERNAL_UNAVAILABLE

不兼容的方法会以编译错误列出。