iphone - 如何在 UIToolbar 内的 UIBarButtonItem Action 中发送发件人

Question

看起来很简单。工具栏内的按钮(在键盘顶部)应该将发送者发送到一个函数。使用下面的代码，我在调试器中收到“发送到实例的无法识别的选择器”。

我的目标是访问自定义单元格的特定 TextField。此代码非常适合识别例如一个开关

工具栏声明:

UIToolbar* itemToolbar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 50)];
itemToolbar.barStyle = UIBarStyleBlackTranslucent;
itemToolbar.items = [NSArray arrayWithObjects:
                     [[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStyleBordered target:self action:@selector(cancelNumberPad)],
                     [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil],
                     [[UIBarButtonItem alloc]initWithTitle:@"Save" style:UIBarButtonItemStyleDone target:self action:@selector(doneWithNumberPad)],
                     nil];
[itemToolbar sizeToFit];

doneWithNumberPad 函数:

- (void)doneWithNumberPad:(id)sender {
    CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.tableView];
    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];
    NSManagedObject *object = [self.fetchedResultsController objectAtIndexPath:indexPath];
    NSLog(@"%@", [object valueForKey:@"item"]);
}

感谢您的帮助

Answer 1

您只需要在保存按钮的选择器方法中包含冒号

itemToolbar.items = [NSArray arrayWithObjects:
                     [[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStyleBordered target:self action:@selector(cancelNumberPad)],
                     [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil],
                     [[UIBarButtonItem alloc]initWithTitle:@"Save" style:UIBarButtonItemStyleDone target:self action:@selector(doneWithNumberPad:)],
                     nil];

sender 的类型为 NSObject，在转换点之前将其转换为 UIBarButtonItem。

- (void)doneWithNumberPad:(id)sender {
    UIBarButtonItem *button = (UIBarButtonItem *)sender;
    CGPoint buttonPosition = [button convertPoint:CGPointZero toView:self.tableView];
    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:buttonPosition];
    NSManagedObject *object = [self.fetchedResultsController objectAtIndexPath:indexPath];
    NSLog(@"%@", [object valueForKey:@"item"]);
}