Sending e-mail in background from iOS apps using SMTP gmail account

The iOS SDK has made it really easy to send email using the built-in APIs. With a few line of codes, you can launch the same email interface as the stock Mail app that lets you compose an email. You can pop up mail composer form , write message and can send plain mail or file attached mail using MFMailComposeViewController class. For more info : Sending e-mail from your iOS App

But, in this section what i am going to explain is about sending emails without showing the mail composer sheet ie. sending emails in background. For this feature, we can not use iOS native MFMailComposer class because it does not allow us to send emails in background instead it pop ups the mail composer view from where user have to tap "send" button , so for this section i am going to use  SKPSMTPMessage Library to send emails in background, however email account has to be hardcoded on this method.

Limitations :
1. sender/receiver email address has to be hardcoded or you have to grab it using some pop up form in your app where user inputs sender/receiver email address. In addition, sender account credentials has to be also hardcoded since there is no way we can grab it from device settings.

Method :
1. Import CFNetwork.framework to your project.
2. Include     #import "SKPSMTPMessage.h"

                    #import "NSData+Base64Additions.h" // for Base64 encoding

3. Include <SKPSMTPMessageDelegate> to your ViewController

4.  Download SKPSMTPMessage library from  

                                             https://github.com/jetseven/skpsmtpmessage

5. Drag and Drop "SMTPLibrary" folder you have downloaded to your project.

  Before proceeding, let you know that i am using sender/receiver email address and sender password hardcoded in the code for this example.But, you may grab this credentials from user, allowing them to input in some sort of forms(using UIViews).



-(void) sendEmailInBackground {

            NSLog(@"Start Sending");

            SKPSMTPMessage *emailMessage = [[SKPSMTPMessage alloc] init];

            emailMessage.fromEmail = @"sender@gmail.com"; //sender email address

            emailMessage.toEmail = @"receiver@gmail.com";  //receiver email address

            emailMessage.relayHost = @"smtp.gmail.com";

            //emailMessage.ccEmail =@"your cc address";

           //emailMessage.bccEmail =@"your bcc address";

            emailMessage.requiresAuth = YES;

            emailMessage.login = @"sender@gmail.com"; //sender email address

            emailMessage.pass = @"Passwxxxx"; //sender email password

            emailMessage.subject =@"@"email subject header message";

            emailMessage.wantsSecure = YES; 

            emailMessage.delegate = self; // you must include <SKPSMTPMessageDelegate> to your class

           NSString *messageBody = @"your email body message";

         //for example :   NSString *messageBody = [NSString stringWithFormat:@"Tour Name: %@\nName: %@\nEmail: %@\nContact No: %@\nAddress: %@\nNote: %@",selectedTour,nameField.text,emailField.text,foneField.text,addField.text,txtView.text];

      // Now creating plain text email message

 NSDictionary *plainMsg = [NSDictionary

                        dictionaryWithObjectsAndKeys:@"text/plain",kSKPSMTPPartContentTypeKey,                               

 messageBody,kSKPSMTPPartMessageKey,@"8bit",kSKPSMTPPartContentTransferEncodingKey,nil];

  emailMessage.parts = [NSArray arrayWithObjects:plainMsg,nil];

            //in addition : Logic for attaching file with email message.

         /*

    NSString *filePath = [[NSBundle mainBundle] pathForResource:@"filename" ofType:@"JPG"];

    NSData *fileData = [NSData dataWithContentsOfFile:filePath];

    NSDictionary *fileMsg = [NSDictionary dictionaryWithObjectsAndKeys:@"text/directory;\r\n\tx-

unix-mode=0644;\r\n\tname=\"filename.JPG\"",kSKPSMTPPartContentTypeKey,@"attachment;\r\n\tfilename=\"filename.JPG\"",kSKPSMTPPartContentDispositionKey,[fileData encodeBase64ForData],kSKPSMTPPartMessageKey,@"base64",kSKPSMTPPartContentTransferEncodingKey,nil];

  emailMessage.parts = [NSArray arrayWithObjects:plainMsg,fileMsg,nil]; //including plain msg and attached file msg

            */

            [emailMessage send];

     // sending email- will take little time to send so its better to use indicator with message showing sending...

}

Now, handling delegate methods :
// On success

-(void)messageSent:(SKPSMTPMessage *)message{

    NSLog(@"delegate - message sent");

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Message sent." message:nil delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles: nil];

[alert show]; 

}

// On Failure

-(void)messageFailed:(SKPSMTPMessage *)message error:(NSError *)error{

// open an alert with just an OK button

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error!" message:[error localizedDescription] delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles: nil];

[alert show];

NSLog(@"delegate - error(%d): %@", [error code], [error localizedDescription]);

}

Ok, thats all from the coding side. hope this tutorial may find useful for you guyz.

In Addition, here are this list of issues  you may find during this tutorial and its solution :

1. If your project ARC is enabled and library has ARC disabled code  then you can disable your project ARC by going through your project target -> Build Settings ->Objective-c Automatic Reference Counting -> set NO
Or, if you only want to disable ARC for those library files only then  you can do it as :  To disable ARC for source files in Xcode 4, select the project and the target in Xcode. Under the target "Build Phases" tab, expand the Compile Sources build phase, select the library source files(.m file), then press Enter to open an edit field, and type -fno-objc-arc as the compiler flag for those files.
 

2. If you have encountered compiling error like  this in pic :

Then solution is go to your project target -> Build Phases -> Compile Sources -> add your all the .m class of your SMTP library . just like in this picture :