Question

当我触摸TableView

时，我使用此方法获取indexPath

-(NSIndexPath *)tableView:(UITableView *)tableView willDeselectRowAtIndexPath:(NSIndexPath *)indexPath{
    if (indexPath.row==0) {
        return nil;
    }else{
        return indexPath;
    }
}

我想将NSString传输到第二个viewController，所以我的代码就像这样

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
    NSIndexPath *indexPath = [self.tableView indexPathForCell:sender];
    NSString *name =self.nameArray[indexPath.row];
    [segue.destinationViewController navigationItem].title = name;
    id theSegue = segue.destinationViewController;
    [theSegue setValue:name forKey:@"showName"];
    }

但indexPath总是为nil，而-tableView:tableView willDeselectRowAtIndexPath indexPath可能不会执行。

那么当我触摸单元格时如何获得正确的indexPath？感谢。

Answer 1

尝试以下代码

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // set Segue Identifier from your first viewcontroller to second viewController in stoaryboard
    [self performSegueWithIdentifier:@"firstVCToSecondVCSegueIdentifier" sender:indexPath];
}

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue.identifier isEqualToString:@"firstVCToSecondVCSegueIdentifier"])
    {
        if ([sender isKindOfClass:[NSIndexPath class]])
        {
            NSIndexPath *indexPath = (NSIndexPath *)sender;
            if ([segue.destinationViewController isKindOfClass:[SecondVC class]]) {
                SecondVC *aSecondVC = (SecondVC*)segue.destinationViewController;
                NSString *name =self.nameArray[indexPath.row];
                aSecondVC.title = name;
            }
        }
    }
}

Answer 2

试试这个::

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
 {
       [self performSegueWithIdentifier:@"YOUR_IDENTIFIER" sender:nil];

   nslog(@"tag :: %@", indexpath.row);
}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
    CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.tableView];
        NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];
        if (indexPath != nil)
        {
     NSString *name =self.nameArray[indexPath.row];
    [segue.destinationViewController navigationItem].title = name;
    id theSegue = segue.destinationViewController;
    [theSegue setValue:name forKey:@"showName"];
        }
    }

Answer 3

试试这个

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
     [self performSegueWithIdentifier:@"YOUR_IDENTIFIER" sender:nil];
}
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
    CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.tableView];
        NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];
        if (indexPath != nil)
        {
     NSString *name =self.nameArray[indexPath.row];
    [segue.destinationViewController navigationItem].title = name;
    id theSegue = segue.destinationViewController;
    [theSegue setValue:name forKey:@"showName"];
        }
    }

希望这有帮助。

Answer 4

在用户更改选择之前，使用- (nullable NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath方法b＆＃39;来调用它。返回新的indexPath或nil，以更改建议的选择。

iOS-indexPath始终返回nil

4 个答案: