向下拉伸tableview头图的发生尺寸

tableViewheader下拉放大.zip

说明&＃xff1a;当tableView下拉的时候&＃xff0c;上面的图根据偏移量改变尺寸&＃xff0c;当偏移量为负值的时候(下拉)&＃xff0c;可以改变尺寸&＃xff0c;当偏移量为正值的时候(上拉),不改变尺寸。

#import "ViewController.h"&＃64;interface ViewController ()<UITableViewDelegate,UITableViewDataSource>&＃64;property (weak, nonatomic) IBOutlet UITableView *tableView;
&＃64;property (nonatomic,retain) UIView *headerView; //头部view&＃64;end&＃64;implementation ViewController- (void)viewDidLoad {[super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.[self.view addSubview:self.headerView];self.tableView.delegate &＃61; self;self.tableView.dataSource &＃61; self;}#pragma mark 设置每行的高度
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {return 60;
}#pragma mark 设置section的个数
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {return 1;
}#pragma mark 设置每个section的行数
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {return 20;
}#pragma mark cellForRow方法
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {static NSString *cellIdentifier &＃61; &＃64;"cell";UITableViewCell *cell &＃61; [tableView dequeueReusableCellWithIdentifier:cellIdentifier];if (cell &＃61;&＃61; nil) {cell &＃61; [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];}// 设置选择时的状态cell.selectionStyle &＃61; UITableViewCellSelectionStyleDefault;// 设置cell背景色为透明色cell.backgroundColor &＃61; [UIColor clearColor];return cell;
}#pragma mark 添加点击cell的方法
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {//点击以后直接恢复正常状态[tableView deselectRowAtIndexPath:indexPath animated:YES];
}- (void)scrollViewDidScroll:(UIScrollView *)scrollView {if (scrollView.contentOffset.y<0) {self.headerView.frame &＃61; CGRectMake(scrollView.contentOffset.y/200*WIDTH/2, 0, (200-scrollView.contentOffset.y)/200*WIDTH, 200-scrollView.contentOffset.y);}NSLog(&＃64;"正在滑动");
}- (UIView *)headerView {if (!_headerView) {_headerView &＃61; [[UIView alloc] init];_headerView.frame &＃61; CGRectMake(0, 0, WIDTH, 200);UIImageView *imageView &＃61; [[UIImageView alloc] init];imageView.image &＃61; [UIImage imageNamed:&＃64;"图片"];[_headerView addSubview:imageView];imageView.translatesAutoresizingMaskIntoConstraints &＃61; NO;NSArray *hConstranits &＃61; [NSLayoutConstraint constraintsWithVisualFormat:&＃64;"H:|-0-[imageView]-0-|" options:0 metrics:nil views:&＃64;{&＃64;"imageView":imageView}];NSArray *vConstranits &＃61; [NSLayoutConstraint constraintsWithVisualFormat:&＃64;"V:|-0-[imageView]-0-|" options:0 metrics:nil views:&＃64;{&＃64;"imageView":imageView}];[_headerView addConstraints:hConstranits];[_headerView addConstraints:vConstranits];}return _headerView;
}- (void)didReceiveMemoryWarning {[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}&＃64;end