在6个单元格之后,UIButton Tag未被分配indexPath.row

Question

我在这里遇到一个奇怪的问题.我有一个TableView,我将indexPath.row分配给UIButton的标记,因此我可以将该标记作为参数传递给segue,并将对象提供给下一个视图控制器.一切都很有效,直到我在TableView中经过6个单元格,按下按钮时会从数组中传递错误的对象.我决定放入一些NSLog来看看发生了什么,我发现结果非常奇怪.赋值buttonForApplyingTag.tag = indexPath.row;发生在NSLog之后,是之前的最后一个语句return cell;.由于indexPath.row的实际值是正确的,因此正确地加载了数组中的对象.它只是导致问题的按钮.这是我的输出:

2012-11-28 19:01:57.596  IndexPath.row: 0
2012-11-28 19:01:57.596  IndexPath.Row from Tag: 0
2012-11-28 19:01:57.597  SearchResults Count: 100
2012-11-28 19:01:57.598  IndexPath.row: 1
2012-11-28 19:01:57.598  IndexPath.Row from Tag: 1
2012-11-28 19:01:57.598  SearchResults Count: 100
2012-11-28 19:01:57.599  IndexPath.row: 2
2012-11-28 19:01:57.600  IndexPath.Row from Tag: 2
2012-11-28 19:01:57.600  SearchResults Count: 100
2012-11-28 19:01:57.601  IndexPath.row: 3
2012-11-28 19:01:57.601  IndexPath.Row from Tag: 3
2012-11-28 19:01:57.602  SearchResults Count: 100
2012-11-28 19:01:57.602  IndexPath.row: 4
2012-11-28 19:01:57.603  IndexPath.Row from Tag: 4
2012-11-28 19:01:57.603  SearchResults Count: 100
2012-11-28 19:01:57.604  IndexPath.row: 5
2012-11-28 19:01:57.605  IndexPath.Row from Tag: 5
2012-11-28 19:01:57.605  SearchResults Count: 100
2012-11-28 19:02:02.004  IndexPath.row: 6
2012-11-28 19:02:02.004  IndexPath.Row from Tag: 6
2012-11-28 19:02:02.005  SearchResults Count: 100
2012-11-28 19:02:03.993  IndexPath.row: 7
2012-11-28 19:02:03.993  IndexPath.Row from Tag: 0
2012-11-28 19:02:03.993  SearchResults Count: 100
2012-11-28 19:02:17.846  IndexPath.row: 8
2012-11-28 19:02:17.846  IndexPath.Row from Tag: 0
2012-11-28 19:02:17.846  SearchResults Count: 100
2012-11-28 19:02:18.482  IndexPath.row: 9
2012-11-28 19:02:18.482  IndexPath.Row from Tag: 0
2012-11-28 19:02:18.482  SearchResults Count: 100

对不起,过多的行,但你明白了.这种趋势一直持续到100,这意味着按钮没有收到正确的标签.甚至更奇怪的是,当使用错误的indexPath.row标记单击按钮时,显然会组成另一个标记,并且我得到一个低值标记.此外,当单元格6部分出现在TableView的底部时,即使单元格已经实际加载,NSLog也没有发布到调试器,因此按钮失败并返回5的标记.所以这种做事方式实际上有3个问题.

真的,我想问的是为什么会发生这种奇怪的行为,我该如何解决？其次,由于这似乎是一场灾难,有没有更好的方法来传递indexPath.row值,以便在单击按钮时从数组中获取对象？

谢谢你的帮助.
问候,
迈克

PS我是一个完全的业余爱好者所以如果你能用莱曼的术语解释它,我会很感激.

编辑:这是我按照要求将标签实际分配给按钮的代码.

    UIButton *buttonForApplyingTag = (UIButton *)[cell viewWithTag:1004];

    NSLog(@"IndexPath.row: %d", indexPath.row);
    NSLog(@"IndexPath.Row from Tag: %d", buttonForApplyingTag.tag);
    NSLog(@"SearchResults Count: %d", [searchResults count]);
    buttonForApplyingTag.tag = indexPath.row;

    return cell;

编辑2:这是整个cellForRowAtIndexPath代码:

if (isLoading) {
    return [tableView dequeueReusableCellWithIdentifier:LoadingCellIdentifier];
} else if ([searchResults count] == 0) {
    return [tableView dequeueReusableCellWithIdentifier:NothingFoundCellIdentifier];
} else {

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SearchResultCellIdentifier];
    [tableView setSeparatorStyle:UITableViewCellSeparatorStyleSingleLine];
    [tableView setSeparatorColor:[UIColor grayColor]];
    /* Then we do a load of assignments for labels in the cell, then we reach the tagging code. */

SearchResultCellIdentifier 来自这个: static NSString *const SearchResultCellIdentifier = @"SearchResultCellProto";

Answer 1

看起来你想要做的是在单元格中有按钮,然后知道按钮动作发生时按下了哪个单元格的按钮.使用标签是一个合理的想法,但很难实现,因为标签需要在单元格重用时更改(并最终在不同的索引路径).

这是一个更好的方法:使用常量标记(或没有标记)添加按钮,然后在单击操作上执行此操作...

- (IBAction)pressedButtonInMyCell:(id)sender {

    UIButton *button = (UIButton *)sender;

    // find the cell that contains the button, this might be one or two levels
    // up depending on how you created the button (one level in code, two in IB, probably)
    UIView *view = button.superview;
    while (view && ![view isKindOfClass:[UITableViewCell self]]) view = view.superview;

    UITableViewCell *cell = (UITableViewCell *)view;
    NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
    NSLog(@"cell is in section %d, row %d", indexPath.section, indexPath.row);
}