为什么我的表视图没有调用委托方法？

Question

我正在构建基于文档的Mac应用程序.我有两个类myDocument和Person.我遇到的困难是当我按下按钮在表视图中添加一个新Person并显示它时它不会在表视图中显示.我已将日志语句放在委托方法中.由于我的日志语句没有显示在控制台中,我知道它们没有被调用.以下是委托方法的实现

    - (int)numberOfRowsInTableView:(NSTableView *)aTableView
    {
        return [employees count];
    }

    - (id)tableView:(NSTableView *)aTableView
    objectValueForTableColumn:(NSTableColumn *)aTableColumn
                row:(int)rowIndex
    {
        // What is the identifier for the column?
        NSString *identifier = [aTableColumn identifier];
        NSLog(@"the identifier's name is : %s",identifier);
        // What person?
        Person *person = [employees objectAtIndex:rowIndex];

        // What is the value of the attribute named identifier?
        return [person valueForKey:identifier];
    }

    - (void)tableView:(NSTableView *)aTableView
       setObjectValue:(id)anObject
       forTableColumn:(NSTableColumn *)aTableColumn
                  row:(int)rowIndex
    {
        NSString *identifier = [aTableColumn identifier];
        Person *person = [employees objectAtIndex:rowIndex];
        NSLog(@"inside the setObjectMethod: %@",person);

        // Set the value for the attribute named identifier
        [person setValue:anObject forKey:identifier];

    [tableView reloadData];
}

这是我的.xib图片

这是我的行动方法

#pragma mark Action Methods
-(IBAction)createEmployee:(id)sender
{
    Person *newEmployee = [[Person alloc] init];
    [employees addObject:newEmployee];
    [newEmployee release];
    [tableView reloadData];
    NSLog(@"the new employees name is : %@",[newEmployee personName]);
}
-(IBAction)deleteSelectedEmployees:(id)sender
{
    NSIndexSet *rows = [tableView selectedRowIndexes];

    if([rows count] == 0){
        NSBeep();
        return;
    }
    [employees removeObjectAtIndexs:rows];
    [tableView reloadData];

}

Answer 1

您忘了将文档的tableView插座绑定到实际的表视图.因此,您的reloadData消息将发送到nil.