iphone - 如何在延迟后为 popViewController 设置动画？

Question

我有一个带有选项列表的 UITableViewController。用户点击一个后，我想返回到上一个 View 。不过，对于我正在使用的代码，返回似乎太快了。我想暂停 0.2 秒左右，让用户有时间看到他们的选择被选中。这是我现在使用的代码:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    NSUInteger oldSelection = [[selectedCriteria objectAtIndex:criteriaSection] integerValue];

    [tableView deselectRowAtIndexPath:indexPath animated:YES];
    // Since there's a "none" selection, we don't deselect if the user taps the one that's already selected
    if ([indexPath row] != oldSelection + 1) {
        NSIndexPath *selectionIndexPath = [NSIndexPath indexPathForRow:oldSelection+1 // Shift down for "None"
                                                inSection:[indexPath section]];
        UITableViewCell *checkedCell = [tableView cellForRowAtIndexPath:selectionIndexPath];
        [checkedCell setAccessoryType:UITableViewCellAccessoryNone];

        [[tableView cellForRowAtIndexPath:indexPath] setAccessoryType:UITableViewCellAccessoryCheckmark];
        [selectedCriteria replaceObjectAtIndex:criteriaSection
                                    withObject:[NSNumber numberWithUnsignedInteger:[indexPath row]-1]];     
    }

    [[self navigationController] popViewControllerAnimated:YES];
}

有什么好的方法可以在弹出 View Controller 之前添加一个短暂的延迟？

Answer 1

希望这对您有所帮助。

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

NSUInteger oldSelection = [[selectedCriteria objectAtIndex:criteriaSection] integerValue];

[tableView deselectRowAtIndexPath:indexPath animated:YES];
// Since there's a "none" selection, we don't deselect if the user taps the one that's already selected
if ([indexPath row] != oldSelection + 1) {
    NSIndexPath *selectionIndexPath = [NSIndexPath indexPathForRow:oldSelection+1 // Shift down for "None"
                                            inSection:[indexPath section]];
    UITableViewCell *checkedCell = [tableView cellForRowAtIndexPath:selectionIndexPath];
    [checkedCell setAccessoryType:UITableViewCellAccessoryNone];

    [[tableView cellForRowAtIndexPath:indexPath] setAccessoryType:UITableViewCellAccessoryCheckmark];
    [selectedCriteria replaceObjectAtIndex:criteriaSection
                                withObject:[NSNumber numberWithUnsignedInteger:[indexPath row]-1]];     
}

[self performSelector:@selector(dismissController) withObject:nil afterDelay:0.2];

}

这会让您有 0.2 秒的延迟来调用函数“dismissController”。

函数“dismissController”。

- (void) dismissController {
  [[self navigationController] popViewControllerAnimated:YES];
}