dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.6 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[textView becomeFirstResponder];
});
Do not add subviews directly to the visual effect view itself, instead add them to the -contentView.
modelWithJSON
第一步：将Json转成字典；
第二部：将字典转成model
/*
Apple said:
The top level object is an NSArray or NSDictionary.
All objects are instances of NSString, NSNumber, NSArray, NSDictionary, or NSNull.
All dictionary keys are instances of NSString.
Numbers are not NaN or infinity.
*/