逍遙文工作室

我們所製作的APP，總希望有使用者回饋，來改善使用者體驗，此時可以使用寄信 (Send Mail)的方式，只要使用者有設定電子信箱，即可在APP裡面傳送信件到我們指定的電子信箱。

先在專案中加入框架：MessageUI Framework。接著引入.h檔：MessageUI/MessageUI.h。記得遵從協定MFMailComposeViewControllerDelegate。

-(IBAction)submitButtonClicked:(UIButton *)button
{
    // 先檢查是否有信箱帳號
    if (![MFMailComposeViewController canSendMail]) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"No e-mail account"
                                                        message:@"Please set your e-mail account first."
                                                       delegate:self
                                              cancelButtonTitle:@"OK"
                                              otherButtonTitles: nil];
        [alert show];
        return;
    }
    // 建立物件並指定代理
    MFMailComposeViewController *mailComposeViewController = [[MFMailComposeViewController alloc] init];
    mailComposeViewController.mailComposeDelegate = self;

    NSArray *toAddressList = @[@"happyman.cg@gmail.com"];
    NSArray *ccAddressList = @[@"happyman.cg@gmail.com"];
    NSArray *bccAddressList = @[@"happyman.cg@gmail.com"];

    mailComposeViewController.navigationBar.barStyle = UIBarStyleBlackTranslucent;

    // 設定收件人與主旨等資訊
    [mailComposeViewController setToRecipients:toAddressList];
    [mailComposeViewController setCcRecipients:ccAddressList];
    [mailComposeViewController setBccRecipients:bccAddressList];
    [mailComposeViewController setSubject:@"For HappyMan :)~"];

    // 設定內文並且使用HTML語法
    NSString *siteLink = @"https://cg2010studio.wordpress.com/";
    NSString *blogLink = @"https://cg2010studio.wordpress.com/";
    NSString *emailBody =
    [NSString stringWithFormat:@"%@\n%@\n", siteLink, blogLink];

    [mailComposeViewController setMessageBody:emailBody isHTML:NO];

    // 加入圖片
    UIImage *theImage = [UIImage imageNamed:@"cat pic.jpg"];
    NSData *imageData = UIImageJPEGRepresentation(theImage, 1.0);
    [mailComposeViewController addAttachmentData:imageData mimeType:@"image/jpg" fileName:@"image.jpg"];

    // 顯示電子郵件畫面
    [self presentViewController:mailComposeViewController animated:YES completion:^{}];
}

內文除了可以有文字之外，還可以加入圖片，甚至還可以使用HTML的語法，豐富地表現信件內容。

接著寫delegate來處理相對應的行為。

#pragma mark - MFMailComposeViewControllerDelegate Methods
-(void)mailComposeController:(MFMailComposeViewController *)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error
{
    switch (result)
    {
        case MFMailComposeResultCancelled:
            break;
        case MFMailComposeResultSaved:
            break;
        case MFMailComposeResultSent:
            break;
        case MFMailComposeResultFailed:
            break;

        default:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Email"
                                                            message:@"Sending Failed - Unknown Error:("
                                                           delegate:self
                                                  cancelButtonTitle:@"OK"
                                                  otherButtonTitles: nil];
            [alert show];
        }
            break;
    }
    [self dismissViewControllerAnimated:YES completion:^{}];
}

參考：MFMailComposeViewController 的基本使用方法、How to attach an image from your photo gallery and send it as an image on iPhone。