异常犀利的导航栏动态高度切换

/** 屏幕宽高 */
#define SCREEN_W [UIScreen mainScreen].bounds.size.width
#define SCREEN_H [UIScreen mainScreen].bounds.size.height

#import "ViewController.h"

@interface ViewController ()<UITableViewDelegate,UITableViewDataSource>

@property (nonatomic,strong) UITableView *tableView;
@property (nonatomic,strong) NSArray *dataSource;
@property (nonatomic,assign) CGFloat lastContentOffset;

@property (nonatomic,strong) UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.title = @"导航栏动态高度切换";
    [self.view addSubview:self.tableView];
    [self.view addSubview:self.imageView];
}

#pragma mark - lazy
- (UITableView *)tableView {
    if (!_tableView) {
        _tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStylePlain];
        _tableView.delegate = self;
        _tableView.dataSource = self;
        _tableView.estimatedRowHeight = 0.0;
        _tableView.sectionHeaderHeight = 0.0;
        _tableView.sectionFooterHeight = 0.0;
        _tableView.estimatedSectionHeaderHeight = 0.0;
        _tableView.estimatedSectionFooterHeight = 0.0;
        [_tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:NSStringFromClass([UITableView class])];
    }
    return _tableView;
}

- (UIImageView *)imageView {
    if (!_imageView) {
        _imageView = [[UIImageView alloc] init];
        _imageView.frame = CGRectMake([UIScreen mainScreen].bounds.size.width-60, 400, 60, 60);
        _imageView.image = [UIImage imageNamed:@"zrx4.jpg"];
        _imageView.layer.cornerRadius = 15;
        _imageView.layer.masksToBounds = YES;
        _imageView.contentMode = UIViewContentModeScaleAspectFit;
        _imageView.backgroundColor = [[UIColor redColor] colorWithAlphaComponent:0.1];
    }
    return _imageView;
}

#pragma mark - lazyLoding
- (NSArray *)dataSource {
    if (!_dataSource) {
        _dataSource = [UIFont familyNames];
    }
    return _dataSource;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return self.dataSource.count;
}

//给cell添加动画
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
    //设置Cell的动画效果为3D效果
    //设置y的初始值为0.1；
    cell.layer.transform = CATransform3DMakeScale(0.1, 1, 1);
    //x和y的最终值为1
    [UIView animateWithDuration:0.25f animations:^{
        cell.layer.transform = CATransform3DMakeScale(1, 1, 1);
    }];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:NSStringFromClass([UITableView class])];
    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    cell.textLabel.text = self.dataSource[indexPath.row];
    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    NSLog(@" == %@",self.dataSource[indexPath.row]);
}

#pragma mark - //开始滑动的时候记录位置
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView {
    _lastContentOffset = scrollView.contentOffset.y;
    
    [UIView animateWithDuration:0.25 animations:^{
        self.imageView.frame = CGRectMake([UIScreen mainScreen].bounds.size.width-15, 400, 60, 60);
    }];
}

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
    [UIView animateWithDuration:0.25 animations:^{
        self.imageView.frame = CGRectMake([UIScreen mainScreen].bounds.size.width-60, 400, 60, 60);
    }];
}

- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView {
    if (scrollView.contentOffset.y > _lastContentOffset) {
        [self.navigationController setNavigationBarHidden:YES animated:YES];
        self.tableView.frame = CGRectMake(0, 20, SCREEN_W, SCREEN_H - 20);
        self.view.backgroundColor = [UIColor whiteColor];
    } else {
        [self.navigationController setNavigationBarHidden:NO animated:YES];
        self.tableView.frame = CGRectMake(0, 64, SCREEN_W, SCREEN_H - 64);
        self.view.backgroundColor = [UIColor whiteColor];
    }
}

@end