大家好,我玩了一段时间的ASIHttpRequest
,AFNetworking,今天,我尝试更深入地阅读AFNetworking的源代码,它确实是一个功能强大且设计精良的网络框架,现在我有几个问题要问:
1、AFJSONRequestOperation
:
NSMutableURLRequest *request = [httpClient requestWithMethod:@"POST" path:kMobileBind parameters:paramsBase];
AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) { //successblock } fail:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON){ //failblock }
在此之后,创建的操作以及成功 block 和失败 block 都设置给它,然后我们开始操作,它在单例线程中启动NSURLconnection
,
[self performSelector:@selector(operationDidStart) onThread:[[self class] networkRequestThread] withObject:nil waitUntilDone:NO modes:[self.runLoopModes allObjects]];
里面的操作DidStart:
[self.lock lock];
NSRunLoop *runLoop = [NSRunLoop currentRunLoop];
for (NSString *runLoopMode in self.runLoopModes) {
[self.connection scheduleInRunLoop:runLoop forMode:runLoopMode];
[self.outputStream scheduleInRunLoop:runLoop forMode:runLoopMode];
}
[self.connection start];
[self.lock unlock];
此操作运行并调用 NSURLconnection
回调,
- (void)connectionDidFinishLoading:(NSURLConnection *)__unused connection {
self.responseData = [self.outputStream propertyForKey:NSStreamDataWrittenToMemoryStreamKey];
[self.outputStream close];
[self finish];
self.connection = nil;
}
- (void)finish {
self.state = AFHTTPOperationFinishedState;
}
finish 方法设置操作的状态,它使用 KVO 技术来完成操作: 我没有看到 observeValueForKeyPath 和 [obj addObserver:self forKeyPath:@"isFinished"options:0 context:NULL]; KVO 是如何工作的?
设置状态:
[self willChangeValueForKey:newStateKey];
[self willChangeValueForKey:oldStateKey];
_state = state;
[self didChangeValueForKey:oldStateKey];
[self didChangeValueForKey:newStateKey];
- (BOOL)isFinished {
return self.state == AFHTTPOperationFinishedState;
}
然后我卡在这里了,我找到了 setcallblock 基金,但无法理解如何调用 self.completionBlock:
- (void)setCompletionBlockWithSuccess:(void (^)(AFHTTPRequestOperation *operation, id responseObject))success
failure:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failure
{
self.completionBlock = ^ {
if ([self isCancelled]) {
return;
}
if (self.error) {
if (failure) {
dispatch_async(self.failureCallbackQueue ? self.failureCallbackQueue : dispatch_get_main_queue(), ^{
failure(self, self.error);
});
}
} else {
if (success) {
dispatch_async(self.successCallbackQueue ? self.successCallbackQueue : dispatch_get_main_queue(), ^{
success(self, self.responseData);
});
}
}
};
可能我确实仔细阅读了代码,但这确实让我很困惑,任何有 AFNetworking 经验的人请解释一下这个框架,
还有一个问题,网络请求是跑在共享线程上的,会不会拖慢请求速度?
我确实想提高我在多线程编程方面的技能,我需要示例和建议,我已经阅读了苹果的文档,并做了一些简单的演示,还没有尝试过大型项目或编写健壮的框架或模型,如何我开始吗?非常感谢
最佳答案
completionBlock
是 AFJSONRequestOperation
的父类(super class) NSOperation
的属性。当操作完成时执行。
关于ios - AFNetworking 究竟是如何工作的?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/18439356/