为什么UIScrollViewDelegate不工作？

Question

我有一个名为"HaveScrollController“的viewController，它是这样的：

@interface HaveScrollController : UIViewController <UIScrollViewDelegate>{
    IBOutlet UIScrollView *scrollView;
    IBOutlet UIView *firstView;
    IBOutlet UIView *secondView;
    IBOutlet UIView *thridView;
    IBOutlet UIView *fourthView;
}


@property (retain, nonatomic) UIScrollView *scrollView;
@property (retain, nonatomic) UIView *firstView;
@property (retain, nonatomic) UIView *secondView;
@property (retain, nonatomic) UIView *thridView;
@property (retain, nonatomic) UIView *fourthView;


@end

.m是这样的：

@synthesize scrollView,firstView,secondView,thridView,fourthView;
- (void)viewDidLoad {
    [super viewDidLoad];
    [self.view addSubview:scrollView];

    scrollView.delegate = self;
}


- (void)scrollViewDidScroll:(UIScrollView *)scrollView{
    NSLog(@"scroll detected");
}

@end

我已经和调查局建立了所有的联系。我想在我的"TestAppController“中使用这个控制器，它不使用IB，而是使用代码生成接口：

@interface TestAppController : UIViewController <UIScrollViewDelegate,UIActionSheetDelegate, UITextFieldDelegate> {
    HaveScrollController *scollViewController;
}

loadView方法中的.m类似于：

scollViewController = [[HaveScrollController alloc] initWithNibName:@"HaveScrollView" bundle:nil];

[mainCanvas addSubview: buttomScollViewController.view];
self.view = mainCanvas;
[mainCanvas release];

当我尝试滚动视图，但没有显示“检测到滚动”时。我做错什么了？谢谢。

Answer 1

scrollView还在滚动吗？看起来您忘记设置contentSize了

scrollView.contentSize = CGSizeMake(320, 400);

显然，要确保contentSize大于scrollView's frame，这样滚动操作才会生效。