indexPathForRowAtPoint不会给我正确的索引

Question

我试图实现一个像界面一样的推特iPhone应用程序。 （滑动以用自定义视图替换tableviewcell中的视图）。我使用Apple的UISwipeGestureRecognizer来识别滑动，并且我使用[recognizer locationInView:self.view]获取了该滑动的起始位置。这给了我一个CGPoint，我用[tableView indexPathForRowAtPoint:location]。我的问题是，我的滑动似乎总是被检测到在我滑过的实际行的上方或下方一行。有没有人遇到过同样的问题？

编辑：我应该也许还提到我使用自定义tableview单元格，它的高度超过了默认视图。我不确定这是否有所作为，我使用heightForRowIndexAtPath:来返回高度。

我的代码 -

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{ 
ModelObject *rowData = (ModelObject *)[tempArr objectAtIndex:indexPath.row]; 
if (rowData.isAlternateView) { 
     // Load alternateview 
    UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipe:)]; 
    [recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)]; 
    [cell addGestureRecognizer:recognizer]; 
    [recognizer release]; 
    return cell; 

} 
else { 
    // Load the correct uitableviewcell 
    UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleSwipe:)]; 
    [recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)]; 
    [cell addGestureRecognizer:recognizer]; 
    [recognizer release]; 

    return cell; 
} 

} 


-(void) handleSwipe:(UISwipeGestureRecognizer *) recognizer 
{ 
NSLog(@"Swipe detected!"); 
CGPoint location = [recognizer locationInView:self.view]; 
NSIndexPath *selectedIndexPath = [tableView indexPathForRowAtPoint:location]; 
NSLog(@"Swipe detected at %d", selectedIndexPath.row); 
ModelObject *rowData = (ModelObject *)[modelArr objectAtIndex:selectedIndexPath.row]; 
rowData.isAlternateView = YES; 

for (int i=0; i<[tempArr count]; i++) { 
    if (i!=selectedIndexPath.row) { 
     ModelObject *rowToBeCleared = (ModelObject *) [modelArr objectAtIndex:i]; 
     if ([rowToBeCleared isAlternateView]) { 
      [rowToBeCleared setIsAlternateView:NO]; 
      [tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:[NSIndexPath indexPathForRow:i inSection:0],nil] withRowAnimation:UITableViewRowAnimationLeft]; 
     } 
    } 
} 

[tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:selectedIndexPath,nil] withRowAnimation:UITableViewRowAnimationRight]; 
} 

Answer 1

第一，而不是添加一个手势识别到每个细胞，我建议只需添加一个手势识别为包含表视图全视图（或者，如果这是一个UITableViewController，然后它们是一样的）。

在viewDidLoad中：

UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] 
    initWithTarget:self action:@selector(handleSwipe:)]; 
[recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)]; 
[self.view addGestureRecognizer:recognizer]; 
[recognizer release]; 

然后，在handleSwipe方法：

- (void)handleSwipe:(UISwipeGestureRecognizer *) recognizer 
{ 
    //might need to check if swipe has ended (otherwise not time to handle yet) 
    if (recognizer.state != UIGestureRecognizerStateEnded) 
     return; 

    CGPoint location = [recognizer locationInView:tableView]; //not self.view 
    NSIndexPath *selectedIndexPath = [tableView indexPathForRowAtPoint:location]; 

    if (selectedIndexPath != nil) 
    { 
     //user swiped on a tableview cell 
    } 
    else 
    { 
     //user did not swipe on a tableview cell 
    } 
}