UITableViewCell自定义accessoryView，通过tag避免因为Cell重用导致的button状态重复

- (UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

{

    static NSString *cellIdentifier = @"OnlineCell";

    OnlineTableViewCell *cell = (OnlineTableViewCell*)[tableView dequeueReusableCellWithIdentifier:cellIdentifier];

    if(!cell) {

        cell = [[OnlineTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];

    }

    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];

    btn.frame = CGRectMake(0, 0, 40, 25);

    [btn setTitle:@"下载" forState:UIControlStateNormal];

    [btn setTitle:@"已下载" forState:UIControlStateDisabled];

    [btn addTarget:self action:@selector(btnClicked:event:) forControlEvents:UIControlEventTouchUpInside];

    cell.accessoryView = btn;

    

    ArticleModel *article = [self.articlelist objectAtIndex:indexPath.row];

    btn.tag = [self.articlelist indexOfObject:article];

    if (article.downloaded==1) {

        btn.enabled=NO;

    }

    

    cell.title.text = article.title;

    cell.subtitle.text = article.createtime;

        

    return cell;

}

- ( void )btnClicked:(id)sender event:(id)event

{

    NSSet *touches = [event allTouches];

    UITouch *touch = [touches anyObject];

    CGPoint currentTouchPosition = [touch locationInView:self.pullTableView];

    NSIndexPath *indexPath = [self.pullTableView indexPathForRowAtPoint:currentTouchPosition];

    if (indexPath != nil){

        [self tableView:self.pullTableView accessoryButtonTappedForRowWithIndexPath:indexPath];

    }

}

-(void)tableView:(UITableView *) tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath{

    ArticleModel *article = [self.articlelist objectAtIndex:indexPath.row];

    // 更新当前文章为已下载

    article.downloaded = 1;

    [self.articlelist replaceObjectAtIndex:indexPath.row withObject:article];    

    [self.pullTableView reloadData];

}