osx 代码创建自定义NSMenu & NSMenuItem

//
unichar arrowKey = 'r';
NSString *refresh = [NSString stringWithCharacters:&arrowKey length:1];

//
// NSString *homePage = [NSString stringWithFormat:@"^%c",arrowKey1];
unichar arrowKey2 = 'o';
NSString *homePage = [NSString stringWithCharacters:&arrowKey2 length:1];

//
unichar arrowKey3 = 27;
NSString *esc = [NSString stringWithCharacters:&arrowKey3 length:1];

NSMenuItem *item= [NSApp.mainMenu insertItemWithTitle:@"111" action:nil keyEquivalent:@"" atIndex:1];
NSMenu *submenu=[[NSMenu alloc] initWithTitle:@"ww"];
item.submenu=submenu;
[submenu addItemWithTitle:@"1" action:@selector(dd) keyEquivalent:homePage];//返回首页
[submenu addItemWithTitle:@"2" action:@selector(dd) keyEquivalent:refresh];//刷新
[submenu addItemWithTitle:@"3" action:@selector(dd) keyEquivalent:esc];//exit