Ios 更新UI之前出现的NSURLConnection sendAsynchronousRequest completionHandler日志
我有这段代码可以向服务器发送json字符串Ios 更新UI之前出现的NSURLConnection sendAsynchronousRequest completionHandler日志,ios,objective-c,sendasynchronousrequest,Ios,Objective C,Sendasynchronousrequest,我有这段代码可以向服务器发送json字符串 [NSURLConnection sendAsynchronousRequest:req queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) { if ([data length
[NSURLConnection
sendAsynchronousRequest:req
queue:[[NSOperationQueue alloc] init]
completionHandler:^(NSURLResponse *response,
NSData *data,
NSError *error)
{
if ([data length] >0 && error == nil)
{
NSLog(@"Done");
}
else if ([data length] == 0 && error == nil)
{
NSLog(@"Nothing was downloaded.");
self.resultLabel.text=@"Done!";
self.view.userInteractionEnabled = TRUE;
}
else if (error != nil){
NSLog(@"Error = %@", error);
}
}];
异步请求完成得很好,日志几乎在完成后立即显示。但是,该代码:
self.resultLabel.text=@"Done!";
self.view.userInteractionEnabled = TRUE;
需要10秒钟才能在UI中显示。有人知道为什么会发生这种情况吗?您必须在主线程中执行所有UI更改:
....
if ([data length] == 0 && error == nil) {
dispatch_async(dispatch_get_main_queue(), ^{
self.resultLabel.text=@"Done!";
self.view.userInteractionEnabled = TRUE;
});
}
....
必须在主线程中执行所有UI更改:
....
if ([data length] == 0 && error == nil) {
dispatch_async(dispatch_get_main_queue(), ^{
self.resultLabel.text=@"Done!";
self.view.userInteractionEnabled = TRUE;
});
}
....
是的,一定是那样!谢谢救了我一天:)是的,一定是那样!谢谢救了我一天:)