iOS 下拉刷新和加载更多 (OC\Swift)

浏览数：484 / 时间：2015年06月11日

Swift语言出来之后, 可能还没有第三方的下拉刷新和上提加载, 所以自己用UIRefreshControl控件和UITableView实例的tableFooterView(底部视图)属性结合起来写了一个下拉刷新和点击加载更多的基本实现, 分为OC的代码实现和Swift的代码实现, 希望大家可以指出不足:

Swift代码:

  1 import UIKit
  2 
  3 class ViewController: UITableViewController {
  4 
  5     // 用于显示的数据源
  6     var _dataSource:[String] = []
  7     
  8     // 加载更多 状态 风火轮
  9     var _aiv:UIActivityIndicatorView!
 10     
 11     override func viewDidLoad() {
 12         super.viewDidLoad()
 13         // Do any additional setup after loading the view, typically from a nib.
 14         
 15         // 数据源中的基础数据
 16         for i in 0...2 {
 17             
 18             _dataSource.append("\(i)")
 19         }
 20         
 21         // 初始下拉刷新控件
 22         self.refreshControl = UIRefreshControl()
 23         self.refreshControl?.attributedTitle = NSAttributedString(string: "Pull To Refresh")
 24         self.refreshControl?.tintColor = UIColor.greenColor()
 25         self.refreshControl?.addTarget(self, action: "refresh", forControlEvents: .ValueChanged)
 26         
 27         // 加载更多按扭的背景视图
 28         var tableFooterView:UIView = UIView()
 29         tableFooterView.frame = CGRectMake(0, 0, self.view.bounds.size.width, 44)
 30         tableFooterView.backgroundColor = UIColor.greenColor()
 31         self.tableView.tableFooterView = tableFooterView
 32 
 33         // 加载更多的按扭
 34         let loadMoreBtn = UIButton()
 35         loadMoreBtn.frame = CGRectMake(0, 0, self.view.bounds.width, 44)
 36         loadMoreBtn.setTitle("Load More", forState: .Normal)
 37         loadMoreBtn.setTitleColor(UIColor.lightGrayColor(), forState: .Normal)
 38         loadMoreBtn.addTarget(self, action: "loadMore:", forControlEvents: .TouchUpInside)
 39         tableFooterView.addSubview(loadMoreBtn)
 40         
 41         // 加载更多 状态 风火轮
 42         _aiv = UIActivityIndicatorView(activityIndicatorStyle: .Gray)
 43         _aiv.center = loadMoreBtn.center
 44         tableFooterView.addSubview(_aiv)
 45     }
 46     
 47     // 加载更多方法
 48     func loadMore(sender:UIButton) {
 49         
 50         sender.hidden = true
 51         _aiv.startAnimating()
 52         
 53         dispatch_async(dispatch_get_global_queue(0, 0), { () -> Void in
 54             
 55             self._dataSource.append("\(self._dataSource[self._dataSource.count-1].toInt()! + 1)")
 56             
 57             dispatch_async(dispatch_get_main_queue(), { () -> Void in
 58                 
 59                 sleep(1)
 60                 
 61                 self._aiv.stopAnimating()
 62                 sender.hidden = false
 63 
 64                 self.tableView.reloadData()
 65             })
 66         })
 67     }
 68     
 69     // 下拉刷新方法
 70     func refresh() {
 71         
 72         if self.refreshControl?.refreshing == true {
 73             
 74             self.refreshControl?.attributedTitle = NSAttributedString(string: "Loading...")
 75         }
 76         
 77         dispatch_async(dispatch_get_global_queue(0, 0), { () -> Void in
 78             
 79             self._dataSource.insert("\(self._dataSource[0].toInt()! - 1)", atIndex: 0)
 80             
 81             dispatch_async(dispatch_get_main_queue(), { () -> Void in
 82                 
 83                 sleep(1)
 84                 
 85                 self.refreshControl?.endRefreshing()
 86                 self.refreshControl?.attributedTitle = NSAttributedString(string: "Pull To Refresh")
 87 
 88                 self.tableView.reloadData()
 89             })
 90         })
 91     }
 92     
 93     // tableView dataSource
 94     override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
 95         
 96         return _dataSource.count
 97     }
 98     
 99     override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
100         
101         let identifier = "cell"
102         
103         var cell = tableView .dequeueReusableCellWithIdentifier(identifier) as? UITableViewCell
104         
105         if cell == nil {
106             
107             cell = UITableViewCell(style: .Default, reuseIdentifier: identifier)
108         }
109         
110         cell?.textLabel?.text = "\(_dataSource[indexPath.row])"
111         
112         return cell!
113     }
114 }

OC代码:

  1 #import "ViewController.h"
  2 
  3 @interface ViewController ()
  4 {
  5     // 数据源
  6     NSMutableArray * _dataSource;
  7     
  8     // 风火轮
  9     UIActivityIndicatorView * _aiv;
 10 }
 11 
 12 @end
 13 
 14 @implementation ViewController
 15 
 16 - (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
 17 {
 18     return self;
 19 }
 20 
 21 - (void)viewDidLoad {
 22     [super viewDidLoad];
 23     // Do any additional setup after loading the view, typically from a nib.
 24     
 25     // 初始数据源
 26     _dataSource = [[NSMutableArray alloc] init];
 27     
 28     // 基础数据
 29     for (int i=0; i<3; i++) {
 30         
 31         [_dataSource addObject:[NSString stringWithFormat:@"%d",i]];
 32     }
 33     
 34     // 刷新控件
 35     self.refreshControl = [[UIRefreshControl alloc] init];
 36     self.refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:@"Pull To Refresh"];
 37     self.refreshControl.tintColor = [UIColor greenColor];
 38     [self.refreshControl addTarget:self action:@selector(refresh) forControlEvents:UIControlEventValueChanged];
 39 
 40     // 背景视图
 41     UIView * tableFooterView = [[UIView alloc] init];
 42     tableFooterView.frame = CGRectMake(0, 0, self.view.bounds.size.width, 44);
 43     tableFooterView.backgroundColor = [UIColor greenColor];
 44     self.tableView.tableFooterView = tableFooterView;
 45     
 46     // 加载更多按扭
 47     UIButton * loadMoreBtn = [[UIButton alloc] init];
 48     loadMoreBtn.frame = CGRectMake(0, 0, self.view.bounds.size.width, 44);
 49     [loadMoreBtn setTitle:@"Load More" forState:UIControlStateNormal];
 50     [loadMoreBtn setTitleColor:[UIColor lightGrayColor] forState:UIControlStateNormal];
 51     [loadMoreBtn addTarget:self action:@selector(loadMore:) forControlEvents:UIControlEventTouchUpInside];
 52     [tableFooterView addSubview:loadMoreBtn];
 53 
 54     // 风火轮
 55     _aiv = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
 56     _aiv.center = loadMoreBtn.center;
 57     [tableFooterView addSubview:_aiv];
 58 }
 59 
 60 // 加载更多方法
 61 - (void)loadMore:(UIButton *)sender
 62 {
 63     sender.hidden = YES;
 64     [_aiv startAnimating];
 65     
 66     dispatch_async(dispatch_get_global_queue(0, 0), ^{
 67        
 68         [_dataSource addObject: [NSString stringWithFormat:@"%d", [_dataSource[_dataSource.count-1] intValue] + 1]];
 69         
 70         dispatch_async(dispatch_get_main_queue(), ^{
 71             
 72             sleep(1);
 73             
 74             [_aiv stopAnimating];
 75             sender.hidden = NO;
 76             
 77             [self.tableView reloadData];
 78         });
 79     });
 80 }
 81 
 82 // 下拉刷新方法
 83 - (void)refresh {
 84     
 85     if (self.refreshControl.refreshing) {
 86         
 87         self.refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:@"Loading..."];
 88     }
 89 
 90     dispatch_async(dispatch_get_global_queue(0, 0), ^{
 91         
 92     [_dataSource insertObject:[NSString stringWithFormat:@"%d", [_dataSource[0] intValue] -1] atIndex:0];
 93         
 94         dispatch_async(dispatch_get_main_queue(), ^{
 95             
 96             sleep(1);
 97             
 98             [self.refreshControl endRefreshing];
 99             self.refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:@"Pull To Refresh"];
100             
101             [self.tableView reloadData];
102         });
103     });
104 }
105 
106 // tableView dataSource
107 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
108 
109     return _dataSource.count;
110 }
111 
112 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
113     
114     static NSString * identifier = @"cell";
115     
116     UITableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:identifier];
117     
118     if (cell == nil) {
119         cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier];
120     }
121     
122     cell.textLabel.text = _dataSource[indexPath.row];
123     
124     return cell;
125 }
126 
127 @end