MJRefresh-简单使用

MJRefresh-简单使用

#import <MJRefresh.h>@interface HKTopicViewController ()
/** 当前最后一条帖子数据的描述信息，专门用来加载下一页数据 */
@property (nonatomic, copy) NSString *maxtime;
/** 所有的帖子数据 */
@property (nonatomic, strong) NSMutableArray<HKTopic *> *topics;
/** 请求管理者 */
@property (nonatomic, strong) AFHTTPSessionManager *manager;
@end- (AFHTTPSessionManager *)manager
{if (!_manager) {_manager = [AFHTTPSessionManager manager];}return _manager;
}- (void)viewDidLoad {[super viewDidLoad];self.view.backgroundColor = RGB(206, 206, 206);self.tableView.contentInset = UIEdgeInsetsMake(HKNavMaxY + HKTitlesViewH, 0, HKTabBarH, 0);self.tableView.scrollIndicatorInsets = self.tableView.contentInset;self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;// 注册cellUINib *nib = [UINib nibWithNibName:NSStringFromClass([HKTopicCell class]) bundle:nil];[self.tableView registerNib:nib forCellReuseIdentifier:HKTopicCellId];[self setupRefresh];
}
- (void)setupRefresh
{// 广告条UILabel *label = [[UILabel alloc] init];label.backgroundColor = [UIColor blackColor];label.frame = CGRectMake(0, 0, 0, 30);label.textColor = [UIColor whiteColor];label.text = @"广告";label.textAlignment = NSTextAlignmentCenter;self.tableView.tableHeaderView = label;// headerself.tableView.mj_header = [MJRefreshNormalHeader headerWithRefreshingTarget:self refreshingAction:@selector(loadNewTopics)];// 自动切换透明度self.tableView.mj_header.automaticallyChangeAlpha = YES;[self.tableView.mj_header beginRefreshing];// footerself.tableView.mj_footer = [MJRefreshAutoNormalFooter footerWithRefreshingTarget:self refreshingAction:@selector(loadMoreTopics)];
}
#pragma mark - 数据处理
/***  发送请求给服务器，下拉刷新数据*/
- (void)loadNewTopics
{// 1.取消之前的请求
    [self.manager.tasks makeObjectsPerformSelector:@selector(cancel)];// 2.拼接参数NSMutableDictionary *parameters = [NSMutableDictionary dictionary];parameters[@"a"] = @"list";parameters[@"c"] = @"data";parameters[@"type"] = @(self.type);// 3.发送请求[self.manager GET:HKCommonURL parameters:parameters progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) {// 存储maxtimeself.maxtime = responseObject[@"info"][@"maxtime"];// 字典数组 -> 模型数据self.topics = [HKTopic mj_objectArrayWithKeyValuesArray:responseObject[@"list"]];// 刷新表格
        [self.tableView reloadData];// 结束刷新
        [self.tableView.mj_header endRefreshing];} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {if (error.code != NSURLErrorCancelled) { // 并非是取消任务导致的error，其他网络问题导致的error[SVProgressHUD showErrorWithStatus:@"网络繁忙，请稍后再试！"];}// 结束刷新
        [self.tableView.mj_header endRefreshing];}];
}/***  发送请求给服务器，上拉加载更多数据*/
- (void)loadMoreTopics
{// 1.取消之前的请求
    [self.manager.tasks makeObjectsPerformSelector:@selector(cancel)];// 2.拼接参数NSMutableDictionary *parameters = [NSMutableDictionary dictionary];parameters[@"a"] = @"list";parameters[@"c"] = @"data";parameters[@"type"] = @(self.type);parameters[@"maxtime"] = self.maxtime;// 3.发送请求[self.manager GET:HKCommonURL parameters:parameters progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) {// 存储maxtimeself.maxtime = responseObject[@"info"][@"maxtime"];// 字典数组 -> 模型数据NSArray *moreTopics = [HKTopic mj_objectArrayWithKeyValuesArray:responseObject[@"list"]];// 累加到旧数组的后面
        [self.topics addObjectsFromArray:moreTopics];// 刷新表格
        [self.tableView reloadData];// 结束刷新
        [self.tableView.mj_footer endRefreshing];if (self.topics.count >= 60) {[self.tableView.mj_footer endRefreshingWithNoMoreData];} else {[self.tableView.mj_footer endRefreshing];}} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {if (error.code != NSURLErrorCancelled) { // 并非是取消任务导致的error，其他网络问题导致的error[SVProgressHUD showErrorWithStatus:@"网络繁忙，请稍后再试！"];}// 结束刷新
        [self.tableView.mj_footer endRefreshing];}];
}
#pragma mark - 数据源
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{// 根据数据量显示或者隐藏footerself.tableView.mj_footer.hidden = (self.topics.count == 0);return self.topics.count;
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{// 清除内存缓存
    [[SDImageCache sharedImageCache] clearMemory];
}

 刷新控件的状态：

/** 刷新控件的状态 */
typedef NS_ENUM(NSInteger, MJRefreshState) {/** 普通闲置状态 */MJRefreshStateIdle = 1,/** 松开就可以进行刷新的状态 */MJRefreshStatePulling,/** 正在刷新中的状态 */MJRefreshStateRefreshing,/** 即将刷新的状态 */MJRefreshStateWillRefresh,/** 所有数据加载完毕，没有更多的数据了 */MJRefreshStateNoMoreData
};

①(局部自定义)设置状态文字颜色-自动切换透明度

自定义一个类HKRefreshHeader继承于：MJRefreshNormalHeader

#import "HKRefreshHeader.h"@implementation HKRefreshHeader- (instancetype)initWithFrame:(CGRect)frame
{if (self = [super initWithFrame:frame]) {// 设置状态文字颜色self.stateLabel.textColor = [UIColor blueColor];self.stateLabel.font = [UIFont systemFontOfSize:17];[self setTitle:@"赶紧下拉刷新" forState:MJRefreshStateIdle];[self setTitle:@"松开?上刷新" forState:MJRefreshStatePulling];[self setTitle:@"正在拼命刷新..." forState:MJRefreshStateRefreshing];// 隐藏时间self.lastUpdatedTimeLabel.hidden = YES;// 自动切换透明度self.automaticallyChangeAlpha = YES;}return self;
}@end

②(全部自定义)

自定义一个类HKCustomRefreshHeader继承于：MJRefreshHeader

#import "HKCustomRefreshHeader.h"
@interface HKCustomRefreshHeader()
/** 开关 */
@property (nonatomic, weak) UISwitch *s;
/** logo */
@property (nonatomic, weak) UIImageView *logo;
@end@implementation HKCustomRefreshHeader
- (instancetype)initWithFrame:(CGRect)frame
{if (self = [super initWithFrame:frame]) {UISwitch *s = [[UISwitch alloc] init];[self addSubview:s];self.s = s;UIImageView *logo = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"MainTitle"]];[self addSubview:logo];self.logo = logo;//self.height = 70;//修改高度
    }return self;
}- (void)layoutSubviews
{[super layoutSubviews];self.logo.centerX = self.width * 0.5;self.logo.y =  -  3 * self.logo.height;self.s.centerX = self.width * 0.5;self.s.centerY = self.height * 0.5;
}#pragma mark - 重写Header内部的方法
- (void)setState:(MJRefreshState)state
{[super setState:state];if (state == MJRefreshStateIdle) { // 下拉可以刷新
        [self.s setOn:NO animated:YES];[UIView animateWithDuration:0.25 animations:^{self.s.transform = CGAffineTransformIdentity;}];} else if (state == MJRefreshStatePulling) { // 松开立即刷新
        [self.s setOn:YES animated:YES];[UIView animateWithDuration:0.25 animations:^{self.s.transform = CGAffineTransformMakeRotation(M_PI_2);}];} else if (state == MJRefreshStateRefreshing) { // 正在刷新
        [self.s setOn:YES animated:YES];[UIView animateWithDuration:0.25 animations:^{self.s.transform = CGAffineTransformMakeRotation(M_PI_2);}];}
}
@end

使用：

// header
self.tableView.mj_header = [HKRefreshHeader headerWithRefreshingTarget:self refreshingAction:@selector(loadNewTopics)];

 补充：

MJRefresh 下拉刷新头部不显示的问题

在uicollectionView 头部有偏移量的时候, 往往给其加下拉刷新的的时候 , 头部的字(mj默认的)往往显示不出来, 此时就需要

MJRefreshNormalHeader *header = [MJRefreshNormalHeader headerWithRefreshingBlock:^{}];
header.ignoredScrollViewContentInsetTop = 20;
self.collectionView.mj_header              = header;