how to compose mail when button at index clicked in UIActionSheet?

i am little bit confused how to display mail composer when i clicked email option in UIActionSheet here's my sample code:

-(void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex{
if(buttonIndex == 0)
    {
    NSString *emailTitle = @"Test Email";
    NSString *messageBody = @"iOS programming is so fun!";
    NSArray *toRecipents = [NSArray arrayWithObject:@"support@email.com"];
    MFMailComposeViewController *mc = [[MFMailComposeViewController alloc] init];
    mc.mailComposeDelegate = self;
    [mc setSubject:emailTitle];
    [mc setMessageBody:messageBody isHTML:NO];
    [mc setToRecipients:toRecipents];
    [self presentViewController:mc animated:YES completion:NULL];
}
}