应用在调用 'tableView endUpdates' 时崩溃

Question

我目前正在 UITableViewCell 中实现 inline UIDate picker。

当我 select 单元格位于应插入该单元格的正上方时，我能够显示和隐藏该选取器单元格，这是我期望的行为。但是，如果我 select table 视图中的任何其他单元格，应用程序会崩溃：

*** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /SourceCache/UIKit_Sim/UIKit-3318.16.14/UITableView.m:1582

查看 accepted answer to this SO question 后，我添加了一个异常断点，我发现应用程序在 didSelectRowAtIndexPath 中调用 [tableView endUpdates]; 时崩溃了：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self.tableView deselectRowAtIndexPath:indexPath animated:YES];

    // Check to see if the "Only Alert From" row was selected. The cell with the picker should be below this one.
    if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow  && self.timePickerIsShowing == NO){

        [tableView beginUpdates];
        [self showTimePicker];
        [tableView endUpdates];

    } else{
        [tableView beginUpdates];
        [self hideTimePicker];
        [tableView endUpdates];
        [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
    }
    [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}

也就是说，我不确定如何进行。如果我注释掉对 [tableView endUpdates]; 的调用，当其他单元格被 selected 时应用程序不会崩溃，但具有选择器视图的单元格不会隐藏。有没有人有什么建议？谢谢！

编辑：下面是我的 showTimePicker 和 hideTimePicker 代码：

- (void)showTimePicker
{
    self.timePickerIsShowing = YES;
    self.timePicker.hidden = NO;

    //Create the index path where we insert the cell with the picker
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection];

    [self.tableView beginUpdates];
    [self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    [self.tableView endUpdates];

    self.timePicker.alpha = 0.0f;
    [UIView animateWithDuration:0.25 animations:^{
        self.timePicker.alpha = 1.0f;
        //This is the row where the picker cell should be inserted
        [self.tableView reloadRowsAtIndexPaths:@[[NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection]] withRowAnimation:UITableViewRowAnimationFade];
        [self.tableView reloadData];
    }];
}

- (void)hideTimePicker {
    self.timePickerIsShowing = NO;
    self.timePicker.hidden = YES;

    //Create the index path where we delete the cell with the picker
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:HourTimeZoneRow + 1 inSection:TimeOfDaySection];
    [self.tableView beginUpdates];
    //Delete the picker row
    [self.tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    [self.tableView endUpdates];
    [UIView animateWithDuration:0.25
                     animations:^{
                         self.timePicker.alpha = 0.0f;
                     }
                     completion:^(BOOL finished){
                         self.timePicker.hidden = YES;
                     }];
}

编辑 2：阅读 this SO thread 后，我认为问题可能出在我的 numberOfRowsInSection 方法上：

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    switch (section) {
        case NotificationsSection:
            return TotalPreferencesRows;
            break;
        case RedZoneSection:
            return TotalRedZoneRows;
            break;
        case TimeOfDaySection:
            if (self.timePickerIsShowing) {
                return TotalTimeOfDayRows + 1;
            }
//            else if (self.timePickerIsShowing == NO){
//                return TotalTimeOfDayRows;
//            }
            else{
                return TotalTimeOfDayRows;
            }
            return TotalTimeOfDayRows;
            break;
        default:
            return 0;
            break;
    }
}

Answer 1

不确定这是否是崩溃的根源，但不建议像您在
中那样多次调用 beginUpdates [tableView beginUpdates]; [self showTimePicker]; [tableView endUpdates]; 因为 showTimePicker 调用 [self.tableView beginUpdates];

Answer 2

问题出在您的 didSelectRowAtIndexPath 中，您调用了 hide 方法，即使它可能没有显示。将 else 子句变成 else if，像这样：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self.tableView deselectRowAtIndexPath:indexPath animated:YES];

    // Check to see if the "Only Alert From" row was selected. The cell with the picker should be below this one.
    if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow  && self.timePickerIsShowing == NO){

        [tableView beginUpdates];
        [self showTimePicker];
        [tableView endUpdates];

    } else if (indexPath.section == TimeOfDaySection && indexPath.row == HourTimeZoneRow  && self.timePickerIsShowing == YES){
        [tableView beginUpdates];
        [self hideTimePicker];
        [tableView endUpdates];
        [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
    }
    [self.tableView deselectRowAtIndexPath:indexPath animated:YES];
}

应用在调用 'tableView endUpdates' 时崩溃

App crashes on call to 'tableView endUpdates'

objective-c

uitableview

didselectrowatindexpath

ios