头部图片可伸缩的TableView

Table列表顶部是一张大图，大图可以随着列表的下拉而放大。

其中IScrollView的代理方法scrollViewDidScroll是重点方法。

 

#import "ViewController.h"

#define Imgwidth 828

#define Imgheight 589

#define ScaleImageViewHeight ([UIScreen mainScreen].bounds.size.width*Imgheight/Imgwidth)

@interfaceViewController ()<UITableViewDelegate,UITableViewDataSource,UIScrollViewDelegate>

@property(strong, nonatomic)IBOutletUIImageView *scaleImageView;

@property(weak, nonatomic)IBOutletUITableView *tableView;

@property(strong, nonatomic)IBOutletUIImageView *noScaleImage;

@property(strong, nonatomic)IBOutletUILabel *nicknameLabel;

 

@end

 

@implementationViewController

 

- (void)viewDidLoad {

    [superviewDidLoad];

    self.tableView.delegate= self;

    self.tableView.dataSource= self;

     

}

- (void)viewWillAppear:(BOOL)animated

{

    self.tableView.contentInset= UIEdgeInsetsMake(ScaleImageViewHeight,0,0,0);

    self.scaleImageView.frame= CGRectMake(0, -ScaleImageViewHeight,self.view.frame.size.width, ScaleImageViewHeight);

    [self.tableViewaddSubview:self.scaleImageView];

    self.noScaleImage.frame= CGRectMake(20, -50,48,48);

    [self.tableViewaddSubview:self.noScaleImage];

    self.nicknameLabel.frame= CGRectMake(88, -42,80,30);

    [self.tableViewaddSubview:self.nicknameLabel];

}

 

#pragma - mark UIScrollView Delegate

- (void)scrollViewDidScroll:(UIScrollView*)scrollView

{

   CGFloaty = scrollView.contentOffset.y;

    if(y < -ScaleImageViewHeight)

    {

        CGRectframe = self.scaleImageView.frame;

        frame.size.height= -y;

        frame.origin.y= y;

        self.scaleImageView.frame= frame;

    }

}

 

#pragma - mark UITableView DataSource

- (NSInteger)tableView:(UITableView*)tableView numberOfRowsInSection:(NSInteger)section

{

    return20;

}

 

- (UITableViewCell*)tableView:(UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath

{

    UITableViewCell*cell = [tableView dequeueReusableCellWithIdentifier:@"cell"];

    cell.textLabel.text= [@(indexPath.row)stringValue];

    returncell;

}

@end