iOS 实现类似抖音翻页滚动效果

这里是效果图

参考抖音的滚动效果，需要我们在结束拖动的时候，动画设置偏移量

这里有一个注意点，由于我们是在拖动结束的时候，手动改变tableview的偏移量，

改变了tableView 自身原有的的滚动效果，所以我们

需要讲tableView 的frame的高度设置为三个cell的高度，然后，设置contentInset

的顶部和底部都是cell的高度，否则会导致我们滚动的过程中cell还没有加载出来

，展示成一片空白的效果

直接上代码

//
//  DouyinScrollViewController.m
//  TEXT
//
//  Created by mac on 2024/4/28.
//  Copyright © 2024 刘博. All rights reserved.
//

#import "DouyinScrollViewController.h"
#import "DouyinScrollTableViewCell.h"

static CGFloat const height = 700;

@interface DouyinScrollViewController () <UITableViewDelegate, UITableViewDataSource>

@property (nonatomic, strong) UITableView *tableView;

@property (nonatomic, assign) NSInteger currentIndex;

@property (nonatomic, assign) CGFloat velocity;

@property (nonatomic, strong) NSMutableArray *colorArray;

@end

@implementation DouyinScrollViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    [self.view addSubview:self.tableView];
    self.colorArray = [NSMutableArray array];
    for (int i = 0; i < 10; i ++) {
        int r = arc4random() % 255;
        int g = arc4random() % 255;
        int b = arc4random() % 255;
        CGFloat rr = r / 255.0;
        CGFloat rg = g / 255.0;
        CGFloat rb = b / 255.0;
        UIColor *color = [[UIColor alloc]initWithRed:rr green:rg blue:rb alpha:1];
        [self.colorArray addObject:color];
    }
    [self.tableView reloadData];
    // Do any additional setup after loading the view.
}

#pragma mark - UITableViewDelegate, UITableViewDataSource

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    DouyinScrollTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:NSStringFromClass([DouyinScrollTableViewCell class])];
    [cell updateWithColor:self.colorArray[indexPath.row]];
    //    cell.textLabel.text = [NSString stringWithFormat:@"%ld",indexPath.row];
    //    cell.backgroundColor = self.colorArray[indexPath.row];
    //    if (!cell.contentView.backgroundColor) {
    //        cell.contentView.backgroundColor = self.colorArray[indexPath.row];
    //    }
    //    return cell;
    return cell;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return 10;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return height;
}

#pragma mark - scrolllVIewDelegate

- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    
}

- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
{
    self.velocity = velocity.y;
}

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    dispatch_async(dispatch_get_main_queue(), ^{
        CGPoint translatedPoint = [scrollView.panGestureRecognizer translationInView:scrollView];
        //UITableView禁止响应其他滑动手势
        scrollView.panGestureRecognizer.enabled = NO;
        CGFloat translateCheck = 60;
        NSLog(@"哈哈哈哈获取停止拖动时候的速度%f", self.velocity);
        if (fabs(self.velocity) > 0.4) {
            translateCheck = 8;
        }
        
        
        if(translatedPoint.y < -translateCheck && self.currentIndex < 10) {
            self.currentIndex ++;   //向下滑动索引递增
        }
        if(translatedPoint.y > translateCheck && self.currentIndex > 0) {
            self.currentIndex --;   //向上滑动索引递减
        }
        [UIView animateWithDuration:0.15
                              delay:0.0
                            options:UIViewAnimationOptionCurveEaseOut animations:^{
            //UITableView滑动到指定cell
            [self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:self.currentIndex inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:NO];
        } completion:^(BOOL finished) {
            //UITableView可以响应其他滑动手势
            scrollView.panGestureRecognizer.enabled = YES;
        }];
        
    });
}

#pragma mark - lazy load

- (UITableView *)tableView
{
    if (!_tableView) {
        _tableView = [[UITableView alloc] initWithFrame:CGRectMake(0, 60 - height, CGRectGetWidth(self.view.bounds), height * 3) style:UITableViewStylePlain];
        [_tableView registerClass:[DouyinScrollTableViewCell class] forCellReuseIdentifier:NSStringFromClass([DouyinScrollTableViewCell class])];
        _tableView.rowHeight = height;
        _tableView.contentInset = UIEdgeInsetsMake(height , 0, height, 0);
        _tableView.estimatedRowHeight = height;
        _tableView.delegate = self;
        _tableView.dataSource = self;
        _tableView.backgroundColor = [UIColor redColor];
        _tableView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
        _tableView.separatorInset = UIEdgeInsetsZero;
    }
    return _tableView;
}

/*
 #pragma mark - Navigation
 
 // In a storyboard-based application, you will often want to do a little preparation before navigation
 - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
 // Get the new view controller using [segue destinationViewController].
 // Pass the selected object to the new view controller.
 }
 */

@end