iOS开发 ----- 上拉加载

上拉加载

和前边类似,只是view放的位置不同,计算的方式不一样而已,原理是相同的

源代码在这里

这里是下拉刷新

贴个图,这个就可以看清楚了

就直接贴代码了

////  ViewController.m//  上拉加载////  Created by xiaoma on 15/9/29.//  Copyright (c) 2015年 xiaoma. All rights reserved.//#import "ViewController.h"#import "AFNetworking.h"@interface ViewController ()<UITableViewDataSource,UITableViewDelegate>//tableView@property(strong, nonatomic)UITableView * tableView;//刷新出来的View的总view@property(strong, nonatomic)UIView * refreshView;//上边的字体@property(strong, nonatomic)UILabel * refreshLabel;//当前页@property(assign, nonatomic)NSInteger page;//存放数据的数组@property(strong, nonatomic)NSMutableArray * dataArray;@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.    [self createRefreshView];    [self createTableView];    [self createData];    _dataArray = [[NSMutableArray alloc]init];}//创建刷新的view,在屏幕外边,先添加到屏幕上,然后在添加tableView-(void)createRefreshView{    _refreshView = [[UIView alloc]initWithFrame:CGRectMake(0, 657, 375, 100)];    _refreshView.backgroundColor = [UIColor whiteColor];    _refreshLabel = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 375, 100)];    _refreshLabel.text = @"上拉加载";    _refreshLabel.font = [UIFont systemFontOfSize:30];    _refreshLabel.textColor = [UIColor redColor];    _refreshLabel.textAlignment = NSTextAlignmentCenter;    [_refreshView addSubview:_refreshLabel];    [self.view addSubview:_refreshView];}//创建tableView-(void)createTableView{    _tableView = [[UITableView alloc]initWithFrame:[UIScreen mainScreen].bounds style:UITableViewStylePlain];    _tableView.dataSource = self;    _tableView.delegate = self;    [self.view addSubview:_tableView];}//创建数据,用到AFnetWorking,本来想用NSURLSession的,这个类貌似是由于线程的原因,要手从戳一下屏幕才可以显示数据//效果并不好,所以用了AFNetWorking//下边是解析数据,没什么好说的,-(void)createData{    NSString * path = [NSString stringWithFormat:@"http://iappfree.candou.com:8080/free/applications/limited?currency=rmb&page=%ld",_page];    AFHTTPRequestOperationManager * manager = [AFHTTPRequestOperationManager manager];    [manager GET:path parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {        //继续添加数据        NSArray * array = [responseObject objectForKey:@"applications"];        for (NSDictionary * temp in array) {            [_dataArray addObject:[temp objectForKey:@"name"]];        }        //修改偏移量,这个下边在加载的时候,修改了偏移量,这里改回来        [UIView animateWithDuration:0.2 animations:^{            _tableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0);        } completion:^(BOOL finished) {            //动画结束之后,修改label的文本显示            //然后重载数据            _refreshLabel.text = @"上拉加载";            [_tableView reloadData];        }];    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {    }];}//tableView的相关代理//设置行高-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{    return 80;}//设置有多少条数据-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{    return _dataArray.count;}//有几个区-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{    return 1;}//给cell赋值-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{    static NSString * string = @"cellID";    UITableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:string];    if (!cell) {        cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:string];    }    cell.textLabel.text = [_dataArray objectAtIndex:indexPath.row];    return cell;}//检测tableView的滚动-(void)scrollViewDidScroll:(UIScrollView *)scrollView{    //这里有几个值要说明一下,    //scrollView.contentOffset 这个时偏移量,下拉的时候这个时负数    //scrollView.contentSize 这个一般来说,会比当前的最大偏移量多出一个屏幕左右    //scrollView.frame tableView的frame    NSLog(@"contentOffset : %@",NSStringFromCGPoint(scrollView.contentOffset));    NSLog(@"contentSize   : %@",NSStringFromCGSize(scrollView.contentSize));    NSLog(@"frame         : %@",NSStringFromCGRect(scrollView.frame));    //让上边的动画,跟着table的位置变化而变化,由于时先添加的,所以到带到前边    if (scrollView.contentOffset.y + scrollView.frame.size.height >= scrollView.contentSize.height) {        CGFloat move = scrollView.contentOffset.y + scrollView.frame.size.height - scrollView.contentSize.height;        [UIView animateWithDuration:0.1 animations:^{            _refreshView.frame = CGRectMake(0, 667- move, 375, 100);            [self.view bringSubviewToFront:_refreshView];        }];    }}//tableView滚动结束后调用的方法-(void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate{    //当检测到偏移量多余150点的时候,就让tableView上边空出100点来显示刷新view    //然后显示正在刷新    //重载数据    CGFloat offset = scrollView.contentOffset.y + scrollView.frame.size.height - scrollView.contentSize.height;    if (offset > 150) {        _tableView.contentInset = UIEdgeInsetsMake(0, 0, 100, 0);        _refreshLabel.text = @"正在加载数据";        _page++;        [self createData];    }}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end