iOSbounds学习笔记以及仿写UIScrollView部分功能详解

- (void)viewDidLoad {
  [super viewDidLoad];

  // 红色的背景view
  UIView *view = [[UIView alloc] initWithFrame:CGRectMake(50, 50, 200, 200)];
  view.backgroundColor = [UIColor redColor];
  [self.view addSubview:view];

  // 单击手势
  UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(viewClick:)];
  [tap setNumberOfTouchesRequired:1];
  [view addGestureRecognizer:tap];

  // 蓝色的子view
  UIView *subView = [[UIView alloc] initWithFrame:CGRectMake(0, 190, 10, 10)];
  subView.backgroundColor = [UIColor blueColor];
  [view addSubview:subView];
}

- (void)viewClick:(UITapGestureRecognizer *)gesture
{
  // 获取红色view
  UIView *view = gesture.view;

  // 修改bounds的值
  CGRect bounds = view.bounds;
  bounds.origin.y += 5;
  view.bounds = bounds;

  // 展示bounds的值
  NSLog(@"bounds:%@",NSStringFromCGRect(view.bounds));
}

- (void)viewDidLoad {
  [super viewDidLoad];

  // 仿scrollView
  UIView *myScrollView = [[UIView alloc] initWithFrame:self.view.bounds];
  myScrollView.backgroundColor = [UIColor redColor];
  [self.view addSubview:myScrollView];

  // 滑动手势
  UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGes:)];
  [myScrollView addGestureRecognizer:pan];

  // scrollView的内容
  UIView *blueView = [[UIView alloc] initWithFrame:CGRectMake(50, 50, 10, 10)];
  blueView.backgroundColor = [UIColor blueColor];
  [myScrollView addSubview:blueView];
}

- (void)panGes:(UIPanGestureRecognizer *)gesture
{
  UIView *myScrollView = gesture.view;

  // 获取滑动的位移量
  CGPoint transPoint = [gesture translationInView:myScrollView];
  NSLog(@"%@",NSStringFromCGPoint(transPoint))；

  // 这里总感觉写错了，我脑子笨，有点绕不过来了。头疼
  CGRect bounds = myScrollView.bounds;
  bounds.origin.x -= transPoint.x;
  bounds.origin.y -= transPoint.y;
  myScrollView.bounds = bounds;

  // 复位
  [gesture setTranslation:CGPointZero inView:myScrollView];
}