ObjC的Block中使用weakSelf/strongSelf @weakify/@strongify
首先要说说什么时候使用weakSelf和strongSelf。
下面引用一篇博客《到底什么时候才需要在ObjC的Block中使用weakSelf/strongSelf》的内容：
Objective C 的 Block 是一个很实用的语法，特别是与GCD结合使用，可以很方便地实现并发、异步任务。但是，如果使用不当，Block 也会引起一些循环引用问题(retain cycle)—— Block 会 retain ‘self’，而 ‘self‘ 又 retain 了 Block。因为在 ObjC 中，直接调用一个实例变量，会被编译器处理成 ‘self->theVar’，’self’ 是一个 strong 类型的变量，引用计数会加 1，于是，self retains queue， queue retains block，block retains self。
解决 retain circle
Apple 官方的建议是，传进 Block 之前，把 ‘self’ 转换成 weak automatic 的变量，这样在 Block 中就不会出现对 self 的强引用。如果在 Block 执行完成之前，self 被释放了，weakSelf 也会变为 nil。
示例代码：
__weak __typeof__(self) weakSelf = self;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, ), ^{
[weakSelf doSomething];
});
clang 的文档表示，在 doSomething 内，weakSelf 不会被释放。但，下面的情况除外：
__weak __typeof__(self) weakSelf = self;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, ), ^{
[weakSelf doSomething];
[weakSelf doOtherThing];
});
在 doSomething 中，weakSelf 不会变成 nil，不过在 doSomething 执行完成，调用第二个方法 doOtherThing 的时候，weakSelf 有可能被释放，于是，strongSelf 就派上用场了：
__weak __typeof__(self) weakSelf = self;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, ), ^{
__strong __typeof(self) strongSelf = weakSelf;
[strongSelf doSomething];
[strongSelf doOtherThing];
});
__strong 确保在 Block 内，strongSelf 不会被释放。
总结
- 在 Block 内如果需要访问 self 的方法、变量，建议使用 weakSelf。
- 如果在 Block 内需要多次 访问 self，则需要使用 strongSelf。
-------------------------------分割线---------------------------------------------
以上内容知道了我们为什么要用weakSelf和strongSelf， 为了简单实用一般会定义成宏weakify和strongify，如下：
#ifndef weakify
#if __has_feature(objc_arc) #define weakify( x ) \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Wshadow\"") \
autoreleasepool{} __weak __typeof__(x) __weak_##x##__ = x; \
_Pragma("clang diagnostic pop") #else #define weakify( x ) \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Wshadow\"") \
autoreleasepool{} __block __typeof__(x) __block_##x##__ = x; \
_Pragma("clang diagnostic pop") #endif
#endif #ifndef strongify
#if __has_feature(objc_arc) #define strongify( x ) \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Wshadow\"") \
try{} @finally{} __typeof__(x) x = __weak_##x##__; \
_Pragma("clang diagnostic pop") #else #define strongify( x ) \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Wshadow\"") \
try{} @finally{} __typeof__(x) x = __block_##x##__; \
_Pragma("clang diagnostic pop") #endif
#endif
使用过RAC的同学应该都知道@weakify和@strongify，这两个宏在RAC中是已经定义好的，可以直接用，属于比较牛逼的写法。这两个宏一定成对出现，先@weakify再@strongify.可以很好的管理Block内部对self的引用。可以一步步点开发现其实使用到了C语言中的组合运算符。
@weakify(self);
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, ), ^{
@strongify(self);
[self doSomething];
[self doOtherThing];
});
将其单独提出来如下：
#if DEBUG
#define rac_keywordify autoreleasepool {}
#else
#define rac_keywordify try {} @catch (...) {}
#endif #define rac_weakify_(INDEX, CONTEXT, VAR) \
CONTEXT __typeof__(VAR) metamacro_concat(VAR, _weak_) = (VAR); #define rac_strongify_(INDEX, VAR) \
__strong __typeof__(VAR) VAR = metamacro_concat(VAR, _weak_); #define weakify(...) \
rac_keywordify \
metamacro_foreach_cxt(rac_weakify_,, __weak, __VA_ARGS__) #define strongify(...) \
rac_keywordify \
_Pragma("clang diagnostic push") \
_Pragma("clang diagnostic ignored \"-Wshadow\"") \
metamacro_foreach(rac_strongify_,, __VA_ARGS__) \
_Pragma("clang diagnostic pop") /**
* Executes one or more expressions (which may have a void type, such as a call
* to a function that returns no value) and always returns true.
*/
#define metamacro_exprify(...) \
((__VA_ARGS__), true) /**
* Returns a string representation of VALUE after full macro expansion.
*/
#define metamacro_stringify(VALUE) \
metamacro_stringify_(VALUE) /**
* Returns A and B concatenated after full macro expansion.
*/
#define metamacro_concat(A, B) \
metamacro_concat_(A, B) /**
* Returns the Nth variadic argument (starting from zero). At least
* N + 1 variadic arguments must be given. N must be between zero and twenty,
* inclusive.
*/
#define metamacro_at(N, ...) \
metamacro_concat(metamacro_at, N)(__VA_ARGS__) /**
* Returns the number of arguments (up to twenty) provided to the macro. At
* least one argument must be provided.
*
* Inspired by P99: http://p99.gforge.inria.fr
*/
#define metamacro_argcount(...) \
metamacro_at(, __VA_ARGS__, , , , , , , , , , , , , , , , , , , , ) /**
* Identical to #metamacro_foreach_cxt, except that no CONTEXT argument is
* given. Only the index and current argument will thus be passed to MACRO.
*/
#define metamacro_foreach(MACRO, SEP, ...) \
metamacro_foreach_cxt(metamacro_foreach_iter, SEP, MACRO, __VA_ARGS__) /**
* For each consecutive variadic argument (up to twenty), MACRO is passed the
* zero-based index of the current argument, CONTEXT, and then the argument
* itself. The results of adjoining invocations of MACRO are then separated by
* SEP.
*
* Inspired by P99: http://p99.gforge.inria.fr
*/
#define metamacro_foreach_cxt(MACRO, SEP, CONTEXT, ...) \
metamacro_concat(metamacro_foreach_cxt, metamacro_argcount(__VA_ARGS__))(MACRO, SEP, CONTEXT, __VA_ARGS__) /**
* Identical to #metamacro_foreach_cxt. This can be used when the former would
* fail due to recursive macro expansion.
*/
#define metamacro_foreach_cxt_recursive(MACRO, SEP, CONTEXT, ...) \
metamacro_concat(metamacro_foreach_cxt_recursive, metamacro_argcount(__VA_ARGS__))(MACRO, SEP, CONTEXT, __VA_ARGS__) /**
* In consecutive order, appends each variadic argument (up to twenty) onto
* BASE. The resulting concatenations are then separated by SEP.
*
* This is primarily useful to manipulate a list of macro invocations into instead
* invoking a different, possibly related macro.
*/
#define metamacro_foreach_concat(BASE, SEP, ...) \
metamacro_foreach_cxt(metamacro_foreach_concat_iter, SEP, BASE, __VA_ARGS__) /**
* Iterates COUNT times, each time invoking MACRO with the current index
* (starting at zero) and CONTEXT. The results of adjoining invocations of MACRO
* are then separated by SEP.
*
* COUNT must be an integer between zero and twenty, inclusive.
*/
#define metamacro_for_cxt(COUNT, MACRO, SEP, CONTEXT) \
metamacro_concat(metamacro_for_cxt, COUNT)(MACRO, SEP, CONTEXT) /**
* Returns the first argument given. At least one argument must be provided.
*
* This is useful when implementing a variadic macro, where you may have only
* one variadic argument, but no way to retrieve it (for example, because \c ...
* always needs to match at least one argument).
*
* @code #define varmacro(...) \
metamacro_head(__VA_ARGS__) * @endcode
*/
#define metamacro_head(...) \
metamacro_head_(__VA_ARGS__, ) /**
* Returns every argument except the first. At least two arguments must be
* provided.
*/
#define metamacro_tail(...) \
metamacro_tail_(__VA_ARGS__) /**
* Returns the first N (up to twenty) variadic arguments as a new argument list.
* At least N variadic arguments must be provided.
*/
#define metamacro_take(N, ...) \
metamacro_concat(metamacro_take, N)(__VA_ARGS__) /**
* Removes the first N (up to twenty) variadic arguments from the given argument
* list. At least N variadic arguments must be provided.
*/
#define metamacro_drop(N, ...) \
metamacro_concat(metamacro_drop, N)(__VA_ARGS__) /**
* Decrements VAL, which must be a number between zero and twenty, inclusive.
*
* This is primarily useful when dealing with indexes and counts in
* metaprogramming.
*/
#define metamacro_dec(VAL) \
metamacro_at(VAL, -, , , , , , , , , , , , , , , , , , , , ) /**
* Increments VAL, which must be a number between zero and twenty, inclusive.
*
* This is primarily useful when dealing with indexes and counts in
* metaprogramming.
*/
#define metamacro_inc(VAL) \
metamacro_at(VAL, , , , , , , , , , , , , , , , , , , , , ) /**
* If A is equal to B, the next argument list is expanded; otherwise, the
* argument list after that is expanded. A and B must be numbers between zero
* and twenty, inclusive. Additionally, B must be greater than or equal to A.
*
* @code // expands to true
metamacro_if_eq(0, 0)(true)(false) // expands to false
metamacro_if_eq(0, 1)(true)(false) * @endcode
*
* This is primarily useful when dealing with indexes and counts in
* metaprogramming.
*/
#define metamacro_if_eq(A, B) \
metamacro_concat(metamacro_if_eq, A)(B) /**
* Identical to #metamacro_if_eq. This can be used when the former would fail
* due to recursive macro expansion.
*/
#define metamacro_if_eq_recursive(A, B) \
metamacro_concat(metamacro_if_eq_recursive, A)(B) /**
* Returns 1 if N is an even number, or 0 otherwise. N must be between zero and
* twenty, inclusive.
*
* For the purposes of this test, zero is considered even.
*/
#define metamacro_is_even(N) \
metamacro_at(N, , , , , , , , , , , , , , , , , , , , , ) /**
* Returns the logical NOT of B, which must be the number zero or one.
*/
#define metamacro_not(B) \
metamacro_at(B, , ) // IMPLEMENTATION DETAILS FOLLOW!
// Do not write code that depends on anything below this line.
#define metamacro_stringify_(VALUE) # VALUE
#define metamacro_concat_(A, B) A ## B
#define metamacro_foreach_iter(INDEX, MACRO, ARG) MACRO(INDEX, ARG)
#define metamacro_head_(FIRST, ...) FIRST
#define metamacro_tail_(FIRST, ...) __VA_ARGS__
#define metamacro_consume_(...)
#define metamacro_expand_(...) __VA_ARGS__ // implemented from scratch so that metamacro_concat() doesn't end up nesting
#define metamacro_foreach_concat_iter(INDEX, BASE, ARG) metamacro_foreach_concat_iter_(BASE, ARG)
#define metamacro_foreach_concat_iter_(BASE, ARG) BASE ## ARG // metamacro_at expansions
#define metamacro_at0(...) metamacro_head(__VA_ARGS__)
#define metamacro_at1(_0, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at2(_0, _1, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at3(_0, _1, _2, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at4(_0, _1, _2, _3, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at5(_0, _1, _2, _3, _4, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at6(_0, _1, _2, _3, _4, _5, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at7(_0, _1, _2, _3, _4, _5, _6, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at8(_0, _1, _2, _3, _4, _5, _6, _7, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at9(_0, _1, _2, _3, _4, _5, _6, _7, _8, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at10(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at11(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at12(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at13(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at14(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at15(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at16(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at17(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at18(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at19(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, ...) metamacro_head(__VA_ARGS__)
#define metamacro_at20(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, ...) metamacro_head(__VA_ARGS__) // metamacro_foreach_cxt expansions
#define metamacro_foreach_cxt0(MACRO, SEP, CONTEXT)
#define metamacro_foreach_cxt1(MACRO, SEP, CONTEXT, _0) MACRO(0, CONTEXT, _0) #define metamacro_foreach_cxt2(MACRO, SEP, CONTEXT, _0, _1) \
metamacro_foreach_cxt1(MACRO, SEP, CONTEXT, _0) \
SEP \
MACRO(, CONTEXT, _1) #define metamacro_foreach_cxt3(MACRO, SEP, CONTEXT, _0, _1, _2) \
metamacro_foreach_cxt2(MACRO, SEP, CONTEXT, _0, _1) \
SEP \
MACRO(, CONTEXT, _2) #define metamacro_foreach_cxt4(MACRO, SEP, CONTEXT, _0, _1, _2, _3) \
metamacro_foreach_cxt3(MACRO, SEP, CONTEXT, _0, _1, _2) \
SEP \
MACRO(, CONTEXT, _3) #define metamacro_foreach_cxt5(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4) \
metamacro_foreach_cxt4(MACRO, SEP, CONTEXT, _0, _1, _2, _3) \
SEP \
MACRO(, CONTEXT, _4) #define metamacro_foreach_cxt6(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5) \
metamacro_foreach_cxt5(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4) \
SEP \
MACRO(, CONTEXT, _5) #define metamacro_foreach_cxt7(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6) \
metamacro_foreach_cxt6(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5) \
SEP \
MACRO(, CONTEXT, _6) #define metamacro_foreach_cxt8(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7) \
metamacro_foreach_cxt7(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6) \
SEP \
MACRO(, CONTEXT, _7) #define metamacro_foreach_cxt9(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8) \
metamacro_foreach_cxt8(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7) \
SEP \
MACRO(, CONTEXT, _8) #define metamacro_foreach_cxt10(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9) \
metamacro_foreach_cxt9(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8) \
SEP \
MACRO(, CONTEXT, _9) #define metamacro_foreach_cxt11(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10) \
metamacro_foreach_cxt10(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9) \
SEP \
MACRO(, CONTEXT, _10) #define metamacro_foreach_cxt12(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11) \
metamacro_foreach_cxt11(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10) \
SEP \
MACRO(, CONTEXT, _11) #define metamacro_foreach_cxt13(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12) \
metamacro_foreach_cxt12(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11) \
SEP \
MACRO(, CONTEXT, _12) #define metamacro_foreach_cxt14(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13) \
metamacro_foreach_cxt13(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12) \
SEP \
MACRO(, CONTEXT, _13) #define metamacro_foreach_cxt15(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14) \
metamacro_foreach_cxt14(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13) \
SEP \
MACRO(, CONTEXT, _14) #define metamacro_foreach_cxt16(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15) \
metamacro_foreach_cxt15(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14) \
SEP \
MACRO(, CONTEXT, _15) #define metamacro_foreach_cxt17(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \
metamacro_foreach_cxt16(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15) \
SEP \
MACRO(, CONTEXT, _16) #define metamacro_foreach_cxt18(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17) \
metamacro_foreach_cxt17(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \
SEP \
MACRO(, CONTEXT, _17) #define metamacro_foreach_cxt19(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18) \
metamacro_foreach_cxt18(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17) \
SEP \
MACRO(, CONTEXT, _18) #define metamacro_foreach_cxt20(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19) \
metamacro_foreach_cxt19(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18) \
SEP \
MACRO(, CONTEXT, _19) // metamacro_foreach_cxt_recursive expansions
#define metamacro_foreach_cxt_recursive0(MACRO, SEP, CONTEXT)
#define metamacro_foreach_cxt_recursive1(MACRO, SEP, CONTEXT, _0) MACRO(0, CONTEXT, _0) #define metamacro_foreach_cxt_recursive2(MACRO, SEP, CONTEXT, _0, _1) \
metamacro_foreach_cxt_recursive1(MACRO, SEP, CONTEXT, _0) \
SEP \
MACRO(, CONTEXT, _1) #define metamacro_foreach_cxt_recursive3(MACRO, SEP, CONTEXT, _0, _1, _2) \
metamacro_foreach_cxt_recursive2(MACRO, SEP, CONTEXT, _0, _1) \
SEP \
MACRO(, CONTEXT, _2) #define metamacro_foreach_cxt_recursive4(MACRO, SEP, CONTEXT, _0, _1, _2, _3) \
metamacro_foreach_cxt_recursive3(MACRO, SEP, CONTEXT, _0, _1, _2) \
SEP \
MACRO(, CONTEXT, _3) #define metamacro_foreach_cxt_recursive5(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4) \
metamacro_foreach_cxt_recursive4(MACRO, SEP, CONTEXT, _0, _1, _2, _3) \
SEP \
MACRO(, CONTEXT, _4) #define metamacro_foreach_cxt_recursive6(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5) \
metamacro_foreach_cxt_recursive5(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4) \
SEP \
MACRO(, CONTEXT, _5) #define metamacro_foreach_cxt_recursive7(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6) \
metamacro_foreach_cxt_recursive6(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5) \
SEP \
MACRO(, CONTEXT, _6) #define metamacro_foreach_cxt_recursive8(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7) \
metamacro_foreach_cxt_recursive7(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6) \
SEP \
MACRO(, CONTEXT, _7) #define metamacro_foreach_cxt_recursive9(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8) \
metamacro_foreach_cxt_recursive8(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7) \
SEP \
MACRO(, CONTEXT, _8) #define metamacro_foreach_cxt_recursive10(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9) \
metamacro_foreach_cxt_recursive9(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8) \
SEP \
MACRO(, CONTEXT, _9) #define metamacro_foreach_cxt_recursive11(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10) \
metamacro_foreach_cxt_recursive10(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9) \
SEP \
MACRO(, CONTEXT, _10) #define metamacro_foreach_cxt_recursive12(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11) \
metamacro_foreach_cxt_recursive11(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10) \
SEP \
MACRO(, CONTEXT, _11) #define metamacro_foreach_cxt_recursive13(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12) \
metamacro_foreach_cxt_recursive12(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11) \
SEP \
MACRO(, CONTEXT, _12) #define metamacro_foreach_cxt_recursive14(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13) \
metamacro_foreach_cxt_recursive13(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12) \
SEP \
MACRO(, CONTEXT, _13) #define metamacro_foreach_cxt_recursive15(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14) \
metamacro_foreach_cxt_recursive14(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13) \
SEP \
MACRO(, CONTEXT, _14) #define metamacro_foreach_cxt_recursive16(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15) \
metamacro_foreach_cxt_recursive15(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14) \
SEP \
MACRO(, CONTEXT, _15) #define metamacro_foreach_cxt_recursive17(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \
metamacro_foreach_cxt_recursive16(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15) \
SEP \
MACRO(, CONTEXT, _16) #define metamacro_foreach_cxt_recursive18(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17) \
metamacro_foreach_cxt_recursive17(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16) \
SEP \
MACRO(, CONTEXT, _17) #define metamacro_foreach_cxt_recursive19(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18) \
metamacro_foreach_cxt_recursive18(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17) \
SEP \
MACRO(, CONTEXT, _18) #define metamacro_foreach_cxt_recursive20(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19) \
metamacro_foreach_cxt_recursive19(MACRO, SEP, CONTEXT, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18) \
SEP \
MACRO(, CONTEXT, _19) // metamacro_for_cxt expansions
#define metamacro_for_cxt0(MACRO, SEP, CONTEXT)
#define metamacro_for_cxt1(MACRO, SEP, CONTEXT) MACRO(0, CONTEXT) #define metamacro_for_cxt2(MACRO, SEP, CONTEXT) \
metamacro_for_cxt1(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt3(MACRO, SEP, CONTEXT) \
metamacro_for_cxt2(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt4(MACRO, SEP, CONTEXT) \
metamacro_for_cxt3(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt5(MACRO, SEP, CONTEXT) \
metamacro_for_cxt4(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt6(MACRO, SEP, CONTEXT) \
metamacro_for_cxt5(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt7(MACRO, SEP, CONTEXT) \
metamacro_for_cxt6(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt8(MACRO, SEP, CONTEXT) \
metamacro_for_cxt7(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt9(MACRO, SEP, CONTEXT) \
metamacro_for_cxt8(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt10(MACRO, SEP, CONTEXT) \
metamacro_for_cxt9(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt11(MACRO, SEP, CONTEXT) \
metamacro_for_cxt10(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt12(MACRO, SEP, CONTEXT) \
metamacro_for_cxt11(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt13(MACRO, SEP, CONTEXT) \
metamacro_for_cxt12(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt14(MACRO, SEP, CONTEXT) \
metamacro_for_cxt13(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt15(MACRO, SEP, CONTEXT) \
metamacro_for_cxt14(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt16(MACRO, SEP, CONTEXT) \
metamacro_for_cxt15(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt17(MACRO, SEP, CONTEXT) \
metamacro_for_cxt16(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt18(MACRO, SEP, CONTEXT) \
metamacro_for_cxt17(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt19(MACRO, SEP, CONTEXT) \
metamacro_for_cxt18(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) #define metamacro_for_cxt20(MACRO, SEP, CONTEXT) \
metamacro_for_cxt19(MACRO, SEP, CONTEXT) \
SEP \
MACRO(, CONTEXT) // metamacro_if_eq expansions
#define metamacro_if_eq0(VALUE) \
metamacro_concat(metamacro_if_eq0_, VALUE) #define metamacro_if_eq0_0(...) __VA_ARGS__ metamacro_consume_
#define metamacro_if_eq0_1(...) metamacro_expand_
#define metamacro_if_eq0_2(...) metamacro_expand_
#define metamacro_if_eq0_3(...) metamacro_expand_
#define metamacro_if_eq0_4(...) metamacro_expand_
#define metamacro_if_eq0_5(...) metamacro_expand_
#define metamacro_if_eq0_6(...) metamacro_expand_
#define metamacro_if_eq0_7(...) metamacro_expand_
#define metamacro_if_eq0_8(...) metamacro_expand_
#define metamacro_if_eq0_9(...) metamacro_expand_
#define metamacro_if_eq0_10(...) metamacro_expand_
#define metamacro_if_eq0_11(...) metamacro_expand_
#define metamacro_if_eq0_12(...) metamacro_expand_
#define metamacro_if_eq0_13(...) metamacro_expand_
#define metamacro_if_eq0_14(...) metamacro_expand_
#define metamacro_if_eq0_15(...) metamacro_expand_
#define metamacro_if_eq0_16(...) metamacro_expand_
#define metamacro_if_eq0_17(...) metamacro_expand_
#define metamacro_if_eq0_18(...) metamacro_expand_
#define metamacro_if_eq0_19(...) metamacro_expand_
#define metamacro_if_eq0_20(...) metamacro_expand_ #define metamacro_if_eq1(VALUE) metamacro_if_eq0(metamacro_dec(VALUE))
#define metamacro_if_eq2(VALUE) metamacro_if_eq1(metamacro_dec(VALUE))
#define metamacro_if_eq3(VALUE) metamacro_if_eq2(metamacro_dec(VALUE))
#define metamacro_if_eq4(VALUE) metamacro_if_eq3(metamacro_dec(VALUE))
#define metamacro_if_eq5(VALUE) metamacro_if_eq4(metamacro_dec(VALUE))
#define metamacro_if_eq6(VALUE) metamacro_if_eq5(metamacro_dec(VALUE))
#define metamacro_if_eq7(VALUE) metamacro_if_eq6(metamacro_dec(VALUE))
#define metamacro_if_eq8(VALUE) metamacro_if_eq7(metamacro_dec(VALUE))
#define metamacro_if_eq9(VALUE) metamacro_if_eq8(metamacro_dec(VALUE))
#define metamacro_if_eq10(VALUE) metamacro_if_eq9(metamacro_dec(VALUE))
#define metamacro_if_eq11(VALUE) metamacro_if_eq10(metamacro_dec(VALUE))
#define metamacro_if_eq12(VALUE) metamacro_if_eq11(metamacro_dec(VALUE))
#define metamacro_if_eq13(VALUE) metamacro_if_eq12(metamacro_dec(VALUE))
#define metamacro_if_eq14(VALUE) metamacro_if_eq13(metamacro_dec(VALUE))
#define metamacro_if_eq15(VALUE) metamacro_if_eq14(metamacro_dec(VALUE))
#define metamacro_if_eq16(VALUE) metamacro_if_eq15(metamacro_dec(VALUE))
#define metamacro_if_eq17(VALUE) metamacro_if_eq16(metamacro_dec(VALUE))
#define metamacro_if_eq18(VALUE) metamacro_if_eq17(metamacro_dec(VALUE))
#define metamacro_if_eq19(VALUE) metamacro_if_eq18(metamacro_dec(VALUE))
#define metamacro_if_eq20(VALUE) metamacro_if_eq19(metamacro_dec(VALUE)) // metamacro_if_eq_recursive expansions
#define metamacro_if_eq_recursive0(VALUE) \
metamacro_concat(metamacro_if_eq_recursive0_, VALUE) #define metamacro_if_eq_recursive0_0(...) __VA_ARGS__ metamacro_consume_
#define metamacro_if_eq_recursive0_1(...) metamacro_expand_
#define metamacro_if_eq_recursive0_2(...) metamacro_expand_
#define metamacro_if_eq_recursive0_3(...) metamacro_expand_
#define metamacro_if_eq_recursive0_4(...) metamacro_expand_
#define metamacro_if_eq_recursive0_5(...) metamacro_expand_
#define metamacro_if_eq_recursive0_6(...) metamacro_expand_
#define metamacro_if_eq_recursive0_7(...) metamacro_expand_
#define metamacro_if_eq_recursive0_8(...) metamacro_expand_
#define metamacro_if_eq_recursive0_9(...) metamacro_expand_
#define metamacro_if_eq_recursive0_10(...) metamacro_expand_
#define metamacro_if_eq_recursive0_11(...) metamacro_expand_
#define metamacro_if_eq_recursive0_12(...) metamacro_expand_
#define metamacro_if_eq_recursive0_13(...) metamacro_expand_
#define metamacro_if_eq_recursive0_14(...) metamacro_expand_
#define metamacro_if_eq_recursive0_15(...) metamacro_expand_
#define metamacro_if_eq_recursive0_16(...) metamacro_expand_
#define metamacro_if_eq_recursive0_17(...) metamacro_expand_
#define metamacro_if_eq_recursive0_18(...) metamacro_expand_
#define metamacro_if_eq_recursive0_19(...) metamacro_expand_
#define metamacro_if_eq_recursive0_20(...) metamacro_expand_ #define metamacro_if_eq_recursive1(VALUE) metamacro_if_eq_recursive0(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive2(VALUE) metamacro_if_eq_recursive1(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive3(VALUE) metamacro_if_eq_recursive2(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive4(VALUE) metamacro_if_eq_recursive3(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive5(VALUE) metamacro_if_eq_recursive4(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive6(VALUE) metamacro_if_eq_recursive5(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive7(VALUE) metamacro_if_eq_recursive6(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive8(VALUE) metamacro_if_eq_recursive7(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive9(VALUE) metamacro_if_eq_recursive8(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive10(VALUE) metamacro_if_eq_recursive9(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive11(VALUE) metamacro_if_eq_recursive10(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive12(VALUE) metamacro_if_eq_recursive11(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive13(VALUE) metamacro_if_eq_recursive12(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive14(VALUE) metamacro_if_eq_recursive13(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive15(VALUE) metamacro_if_eq_recursive14(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive16(VALUE) metamacro_if_eq_recursive15(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive17(VALUE) metamacro_if_eq_recursive16(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive18(VALUE) metamacro_if_eq_recursive17(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive19(VALUE) metamacro_if_eq_recursive18(metamacro_dec(VALUE))
#define metamacro_if_eq_recursive20(VALUE) metamacro_if_eq_recursive19(metamacro_dec(VALUE)) // metamacro_take expansions
#define metamacro_take0(...)
#define metamacro_take1(...) metamacro_head(__VA_ARGS__)
#define metamacro_take2(...) metamacro_head(__VA_ARGS__), metamacro_take1(metamacro_tail(__VA_ARGS__))
#define metamacro_take3(...) metamacro_head(__VA_ARGS__), metamacro_take2(metamacro_tail(__VA_ARGS__))
#define metamacro_take4(...) metamacro_head(__VA_ARGS__), metamacro_take3(metamacro_tail(__VA_ARGS__))
#define metamacro_take5(...) metamacro_head(__VA_ARGS__), metamacro_take4(metamacro_tail(__VA_ARGS__))
#define metamacro_take6(...) metamacro_head(__VA_ARGS__), metamacro_take5(metamacro_tail(__VA_ARGS__))
#define metamacro_take7(...) metamacro_head(__VA_ARGS__), metamacro_take6(metamacro_tail(__VA_ARGS__))
#define metamacro_take8(...) metamacro_head(__VA_ARGS__), metamacro_take7(metamacro_tail(__VA_ARGS__))
#define metamacro_take9(...) metamacro_head(__VA_ARGS__), metamacro_take8(metamacro_tail(__VA_ARGS__))
#define metamacro_take10(...) metamacro_head(__VA_ARGS__), metamacro_take9(metamacro_tail(__VA_ARGS__))
#define metamacro_take11(...) metamacro_head(__VA_ARGS__), metamacro_take10(metamacro_tail(__VA_ARGS__))
#define metamacro_take12(...) metamacro_head(__VA_ARGS__), metamacro_take11(metamacro_tail(__VA_ARGS__))
#define metamacro_take13(...) metamacro_head(__VA_ARGS__), metamacro_take12(metamacro_tail(__VA_ARGS__))
#define metamacro_take14(...) metamacro_head(__VA_ARGS__), metamacro_take13(metamacro_tail(__VA_ARGS__))
#define metamacro_take15(...) metamacro_head(__VA_ARGS__), metamacro_take14(metamacro_tail(__VA_ARGS__))
#define metamacro_take16(...) metamacro_head(__VA_ARGS__), metamacro_take15(metamacro_tail(__VA_ARGS__))
#define metamacro_take17(...) metamacro_head(__VA_ARGS__), metamacro_take16(metamacro_tail(__VA_ARGS__))
#define metamacro_take18(...) metamacro_head(__VA_ARGS__), metamacro_take17(metamacro_tail(__VA_ARGS__))
#define metamacro_take19(...) metamacro_head(__VA_ARGS__), metamacro_take18(metamacro_tail(__VA_ARGS__))
#define metamacro_take20(...) metamacro_head(__VA_ARGS__), metamacro_take19(metamacro_tail(__VA_ARGS__)) // metamacro_drop expansions
#define metamacro_drop0(...) __VA_ARGS__
#define metamacro_drop1(...) metamacro_tail(__VA_ARGS__)
#define metamacro_drop2(...) metamacro_drop1(metamacro_tail(__VA_ARGS__))
#define metamacro_drop3(...) metamacro_drop2(metamacro_tail(__VA_ARGS__))
#define metamacro_drop4(...) metamacro_drop3(metamacro_tail(__VA_ARGS__))
#define metamacro_drop5(...) metamacro_drop4(metamacro_tail(__VA_ARGS__))
#define metamacro_drop6(...) metamacro_drop5(metamacro_tail(__VA_ARGS__))
#define metamacro_drop7(...) metamacro_drop6(metamacro_tail(__VA_ARGS__))
#define metamacro_drop8(...) metamacro_drop7(metamacro_tail(__VA_ARGS__))
#define metamacro_drop9(...) metamacro_drop8(metamacro_tail(__VA_ARGS__))
#define metamacro_drop10(...) metamacro_drop9(metamacro_tail(__VA_ARGS__))
#define metamacro_drop11(...) metamacro_drop10(metamacro_tail(__VA_ARGS__))
#define metamacro_drop12(...) metamacro_drop11(metamacro_tail(__VA_ARGS__))
#define metamacro_drop13(...) metamacro_drop12(metamacro_tail(__VA_ARGS__))
#define metamacro_drop14(...) metamacro_drop13(metamacro_tail(__VA_ARGS__))
#define metamacro_drop15(...) metamacro_drop14(metamacro_tail(__VA_ARGS__))
#define metamacro_drop16(...) metamacro_drop15(metamacro_tail(__VA_ARGS__))
#define metamacro_drop17(...) metamacro_drop16(metamacro_tail(__VA_ARGS__))
#define metamacro_drop18(...) metamacro_drop17(metamacro_tail(__VA_ARGS__))
#define metamacro_drop19(...) metamacro_drop18(metamacro_tail(__VA_ARGS__))
#define metamacro_drop20(...) metamacro_drop19(metamacro_tail(__VA_ARGS__))
ObjC的Block中使用weakSelf/strongSelf @weakify/@strongify的更多相关文章
- @weakify, @strongify ObjC的Block中使用weakSelf/strongSelf @weakify/@strongify
首先要说说什么时候使用weakSelf和strongSelf. 下面引用一篇博客<到底什么时候才需要在ObjC的Block中使用weakSelf/strongSelf>的内容: Objec ...
- 到底什么时候才需要在ObjC的Block中使用weakSelf/strongSelf
转载,原文: http://blog.lessfun.com/blog/2014/11/22/when-should-use-weakself-and-strongself-in-objc-block ...
- iOS Block中的weakSelf/strongSelf
Objective C 的 Block 是一个很实用的语法,特别是与GCD结合使用,可以很方便地实现并发.异步任务.但是,如果使用不当,Block 也会引起一些循环引用问题(retain cycle) ...
- 【转载】在block中使用weakSelf/strongSelf
http://blog.lessfun.com/blog/2014/11/22/when-should-use-weakself-and-strongself-in-objc-block/
- iOS 面试题（二）：什么时候在 block 中不需要使用 weakSelf --转自唐巧
问题 我们知道,在使用 block 的时候,为了避免产生循环引用,通常需要使用 weakSelf 与 strongSelf,写下面这样的代码: __weak typeof(self) weakSelf ...
- iOS __weak __strong WeakSelf StrongSelf
在block中常常会用到self,可是会造成循环引用.这时候就需要这样来解决这个问题: #define WeakSelf __weak typeof(self) weakSelf = self #de ...
- 讲述Sagit.Framework解决：双向引用导致的IOS内存泄漏（下）- block中任性用self
前言: 在处理完框架内存泄漏的问题后,见上篇:讲述Sagit.Framework解决:双向引用导致的IOS内存泄漏(中)- IOS不为人知的Bug 发现业务代码有一个地方的内存没释放,原因很也简单: ...
- iOS开发-多层嵌套block中如何使用__weak和__strong
1.关于__weak__weak只能在ARC模式下使用,也只能修饰对象(比如NSString等),不能修饰基本数据类型(比如int等)__weak修饰的对象在block中不可以被重新赋值.__weak ...
- dispatch_async 的 block 中是否该使用_weak self
问题分析 我看过很多文章关于在dispatch_async的block里面使用_weak self, 但是让我疑惑的是,以下代码是否需要必须使用_weak self, 因为我也看到了很多观点说,在有些 ...
随机推荐
- python 核心编程第二版 课后习题 第11章
11-3 函数.在这个练习中,我们将实现 max()和 min()内建函数. (a) 写分别带两个元素返回一个较大和较小元素,简单的 max2()核 min2()函数.他们应该可以用任意的 pytho ...
- Python学习教程(learning Python)--1.2.4 Python格式化输出科学计数
Python在浮点数据输出时,可以采用科学计数法的方式输出. 现举两个例子说明一下如何使用. eg1. 无精度要求的科学计数法浮点数据输出 >>> print(format(1234 ...
- Ruby on Rail学习笔记
说明:只针对Windows8.1 Windows下,上rubyinstaller上下载最新的railsinstaller包含Ruby2.1的,然后更新gem 用命令: gem update --sys ...
- 【转】Oracle中如何用一条SQL快速生成10万条测试数据
转自http://blog.csdn.net/welken/article/details/4971887 做数据库开发或管理的人经常要创建大量的测试数据,动不动就需要上万条,如果一条一条的录入, ...
- 一段高质量的SQL从问问题开始(笔记)
首先SQL书写的目的是为了解决问题,因此只有明白了要解决的问题,才能写出更加高效的SQL语句,才能优雅的解决问题,获得更多的快乐! 在写一个SQL语句的时候不妨像优化器一样思考,问自己以下的这些问题, ...
- UITextField使用的相关方法
1.设置占位符 textField.placeholder = @“”; 2.设置暗文输入 textField.secureTextEntry = YES; 3.设置键盘类型 textField. ...
- 说明一下JNI 与AIDL
代码在评论中. JNI: 为什么需要JNI: 因为android是由[JAVA & C/C++]组成.Java运行在Dalvik虚拟机中. 没有办法直接访问底层硬件.底层HW相关目前技术一般都 ...
- wifi-sdio接口
1.sdio接口层解析 SDIO总线 SDIO总线和USB总线类似,SDIO也有两端,其中一端是HOST端,另一端是device端.所有的通信都是由HOST端发送命令开始的,Device端只要能解析命 ...
- Tornado服务器的学习
Tornado就是我们在 FriendFeed 的 Web 服务器及其常用工具的开源版本.Tornado 和现在的主流 Web 服务器框架(包括大多数 Python 的框架)有着明显的区别:它是非阻塞 ...
- 海蜘蛛ISPV6.1.5,目前破解版本中最稳定的！
海蜘蛛ISPV6.1.5,目前破解版本中最稳定的! 破解步骤如下: 一.安装完毕进控制台 二.使用muddyboot登陆 密码(123456) 三.输入root回车 四.输入regtools回车 五. ...