鼠标右键NSMenu的使用

初始化：

    　　self.rightClickMenu = [[NSMenu alloc] init];
        NSMenuItem *item1 = [[NSMenuItem alloc] initWithTitle:NSLocalizedString(@"Open", @"") action:@selector(rightPlayAction:) keyEquivalent:@""];
        NSMenuItem *item2 = [[NSMenuItem alloc] initWithTitle:NSLocalizedString(@"ExportTo", @"") action:@selector(rightExportAction:) keyEquivalent:@""];
        NSMenuItem *item3 = [[NSMenuItem alloc] initWithTitle:NSLocalizedString(@"Delete", @"") action:@selector(rightDeleteAction:) keyEquivalent:@""];
        [item1 setTarget:self];
        [item2 setTarget:self];
        [item3 setTarget:self];
        [self.rightClickMenu addItem:item1];
        [self.rightClickMenu addItem:[NSMenuItem separatorItem]];
        [self.rightClickMenu addItem:item2];
        [self.rightClickMenu addItem:[NSMenuItem separatorItem]];        
        [self.rightClickMenu addItem:item3];    

使用：

- (NSMenu *)collectionViewMenu:(IBCollectionView *)collectionView IndextSet:(IBSectionIndexSet *)indexSet
{
    return self.rightClickMenu;
}

　禁止某个item是否可用

NSMenuItem *item = self.rightClickMenu.itemArray.firstObject;
item.enabled = NO;        
[item.menu setAutoenablesItems:NO];