视图外观过程中Storyboard和xib之间的不一致

Question

我不明白在视图外观链中询问UIView的框架和/或与Storyboard与传统xib相关的差异是否安全。

我在Xcode 4.5.1中创建了两个不同的，非常简单的单个UIViewController项目;在第一个我使用标准单视图模板与xib，在第二个我使用故事板。 ViewController.m的源代码 - 两个项目相同 - 如下所示。在IB中，我拖入UIScrollView并将其正确连接到我的控制器插座。

正如您在源代码中所述，我正在视图外观链中的不同点注销滚动视图的框架。我不明白为什么它们不同和/或我可以安全地查询UIScrollView框架，因为它是viewDidLoad中的（0,0）。

ViewController.m

#import "ViewController.h"

@interface ViewController ()
@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;
@end

@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    NSLog(@"viewDidLoad scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
- (void)viewWillLayoutSubviews {
    NSLog(@"viewWillLayoutSubviews scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);    
}
- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    NSLog(@"viewWillAppear scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);

}
- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    NSLog(@"viewDidAppear scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
@end

xib

的结果

2012-10-23 11:49:48.316 ScrollTest[83262:c07] viewDidLoad scrollView.frame = (320,548)
2012-10-23 11:49:48.318 ScrollTest[83262:c07] viewWillAppear scrollView.frame = (320,548)
2012-10-23 11:49:48.321 ScrollTest[83262:c07] viewWillLayoutSubviews scrollView.frame = (320,548)
2012-10-23 11:49:48.328 ScrollTest[83262:c07] viewDidAppear scrollView.frame = (320,460)

故事板

的结果

2012-10-23 11:49:58.762 ScrollTestStoryboard[83308:c07] viewDidLoad scrollView.frame = (  0,  0)
2012-10-23 11:49:58.763 ScrollTestStoryboard[83308:c07] viewWillAppear scrollView.frame = (  0,  0)
2012-10-23 11:49:58.765 ScrollTestStoryboard[83308:c07] viewWillLayoutSubviews scrollView.frame = (  0,  0)
2012-10-23 11:49:58.772 ScrollTestStoryboard[83308:c07] viewDidAppear scrollView.frame = (320,460)

Answer 1

答案是viewDidLayoutSubviews。希望我大约20分钟前见过。下面是更新的源代码和日志输出。

ViewController.m

#import "ViewController.h"

@interface ViewController ()
@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;
@end

@implementation ViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    NSLog(@"viewDidLoad scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    NSLog(@"viewWillAppear scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);

}
- (void)viewWillLayoutSubviews {
    NSLog(@"viewWillLayoutSubviews scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
- (void)viewDidLayoutSubviews {
    NSLog(@"viewDidLayoutSubviews scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    NSLog(@"viewDidAppear scrollView.frame = (%3.0f,%3.0f)",self.scrollView.frame.size.width,self.scrollView.frame.size.height);
}
@end

故事板输出

2012-10-23 12:12:35.597 ScrollTestStoryboard[87593:c07] viewDidLoad scrollView.frame = (  0,  0)
2012-10-23 12:12:35.599 ScrollTestStoryboard[87593:c07] viewWillAppear scrollView.frame = (  0,  0)
2012-10-23 12:12:35.601 ScrollTestStoryboard[87593:c07] viewWillLayoutSubviews scrollView.frame = (  0,  0)
2012-10-23 12:12:35.602 ScrollTestStoryboard[87593:c07] viewDidLayoutSubviews scrollView.frame = (320,460)
2012-10-23 12:12:35.609 ScrollTestStoryboard[87593:c07] viewDidAppear scrollView.frame = (320,460)