Toolbars not showing up on MailController

MFMailComposeViewController *mailController = [[MFMa开发者_StackOverflow社区ilComposeViewController alloc] init];

UIBarButtonItem *systemItem1 = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction 
                                                        target:self action:@selector(action];

[mailController setToolbarItems:[NSArray arrayWithObject:systemItem1]];

The systemItem1 UIBarButtonItem is not showing up.

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UIBarButtonItem *btnTemp = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonItemStyleDone target:self action:nil];

[[[[picker viewControllers] lastObject] navigationItem] setRightBarButtonItem:btnTemp]; 

[btnTemp release];

Likewise, you can customize anything from it...BUT

From the MFMailComposeViewController Class Reference: Important: The mail composition interface itself is not customizable and must not be modified by your application. In addition, after presenting the interface, your application is not allowed to make further changes to the email content.

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You are not allowed to modify this view controller. Apple has put measures in place to prevent its editing this way.