Sending mail inside the app with Cocos2D

First of all, I would like to say that if you are looking for a way of sending mails without using the Apple's mail composer you are not looking in the proper site. However I had the same purpose at the beginning, but I didn't want to deal directly with the SMTP protocol and I couldn't find any supported library.

Instead of a custom mail scene, you are going to have the Apple's standard mail composer. Something like that:

Implementing this is not difficult using MFMailComposeViewController, but with Cocos2D you have to pay attention at several points.

The general idea is simple: create the composer, check if it can send mails, set the delegate, fill the mail and tell the controller to show the composer.

So, the steps to follow are;

1. Add the MessageUI framework to the project.
2. Make your class implement MFMailComposeViewController.
3. Instantiate the mail composer
4. Check if the device can send the mail. This checks whether the iPhone Mail app is synchronized with an account or not. In this last case, you should break here and show an error.
5. Set the delegate to self. Your class now must contain the method mailComposeController:didFinishWithResult:error:
6. Fill the mail with the subject, recipients, body...
7. Tell the UI view controller to show the composer

The main problems with Cocos2D are the animation and that you don't work with view controllers, instead you have scenes, layers, ...
For the first problem, it's as easy as pausing the director before showing the composer and resuming it after the mail is sent.
For the controller issue, I found in the cocos-2d forum a solution which involved creating a view controller and setting the view to the openGL view. That worked pretty fine with iOS5, but arise a uncaught exception when testing in iOS6. More than one view controller cannot be associated with the same view.

I finally got to the solution, take the view controller, stored in the appDelegate (it implies a little modification in the appDelegate class), and use it to show the mail view.

Finally, the code should be like that:

	#import <UIKit/UIKit.h>
	@class RootViewController;
	@interface AppDelegate : NSObject <UIApplicationDelegate> {
	UIWindow *window;
	RootViewController *viewController;
	}
	@property (nonatomic, retain) UIWindow *window;
	- (RootViewController *) getVController; //New method
	@end

view raw AppDelegate.h hosted with ❤ by GitHub

	- (RootViewController *) getVController {
	return viewController;
	}

view raw AppDelegate.mm hosted with ❤ by GitHub

	#import <MessageUI/MessageUI.h>
	@interface YourLayer : CCLayer <MFMailComposeViewControllerDelegate> {
	MFMailComposeViewController *picker;
	UIViewController *rootViewController;
	}
	- (void) displayComposerSheet;
	@end

view raw YourLayer.h hosted with ❤ by GitHub

	// Call this method when you want to display the composer
	- (void) displayComposerSheet {
	// Pause the animation
	[[CCDirector sharedDirector] pause];
	// Get the UI view controller
	rootViewController = (UIViewController*)[(AppDelegate*)[[UIApplication sharedApplication] delegate] getVController];
	// Instantiate the mail composer and check if it can send mails
	picker = [[MFMailComposeViewController alloc] init];
	if ((!picker) || ![MFMailComposeViewController canSendMail]) {
	NSLog(@"Impossible to send mail");
	return;
	}
	picker.mailComposeDelegate = self;
	// Fill the mail content
	NSArray *toArray = [NSArray arrayWithObjects:@"recipient1@themail.com",@"recipient2@themail.com", nil];
	[picker setToRecipients:toArray];
	[picker setSubject:@"This test is working!"];
	[picker setMessageBody:@"Oh my God! This is working! Even I can add a <a href=\"http://www.google.com\">link</a>! <br/> Me" isHTML:YES];
	// Display the view
	[rootViewController presentModalViewController:picker animated:YES];
	// We don't need it anymore
	[picker release];
	}
	// This method is triggered on mail composer actions
	- (void)mailComposeController:(MFMailComposeViewController*)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError*)error {
	// Resume the animation
	[[CCDirector sharedDirector] resume];
	// All the possible results
	switch (result) {
	case MFMailComposeResultCancelled:
	NSLog(@"Cancelled");
	break;
	case MFMailComposeResultSaved:
	NSLog(@"Mail saved not sent");
	break;
	case MFMailComposeResultFailed:
	NSLog(@"Failed sending mail");
	break;
	case MFMailComposeResultSent:
	NSLog(@"Mail sent");
	default:
	break;
	}
	// Hide the composer
	[rootViewController dismissModalViewControllerAnimated:YES];
	}

view raw YourLayer.mm hosted with ❤ by GitHub

Remark. All of this is assuming that you are working with cocos2d 1.x. This is reasonable assumption since the new version in cocos2d is quite recent, it has several changes from the older version and doesn't support iOS <4 or iPhone <3GS.
With Cocos2d 2.x and this documentation, I suppose (I haven't tried it yet) that the problem is no more there, because our SharedDirector will be itself our view controller (we don't need to ask the AppDelegate nor create the rootViewController variable)

Add a framework in a XCode project

Since I started programming with more advanced tools (video, mails, analytics, ...)  I've had to add new frameworks to my project.

It's very easy, but I always spend a lot of time looking for the place where I can press this plus button.

On the project navigator select your project (the blue sheet)

Then go to the project-target panel and select your target

On the left grey big panel, on the top menu select the summary tab

Now, look for Linked Frameworks and Libraries and press the plus button

You will see a new window where you can write the new library or framework you want to add

Once you added the framework, you will see it in the project navigator

The beginning: Cocos2D

I didn't have any previous knowledge of Objective-C before I started programming with the framework Cocos2d. I only read a tutorial of the basics of this programming language which was provided by our mentors in the Praktikum I was starting.

It wasn't difficult for me because of my experience in C and OOP in Java. The most difficult thing was remembering the order of the arguments and colons in the signature ;-)

For me it was important to learn on demand. Do you like (or just know, it may be sufficient) functional programming in Haskell? I'm like lazy evaluation ;-) No, just kidding... But it's true in some sense. I started in small team and each one had assigned some tasks with features to be developed. I looked for it in the internet, in my book, ask teammates, ...
The first week I learnt how to set the scene and characters, the next one, how to make an animation with frames, ... All of this tasks were surely not completely correct at the beginning but the knowledge have grown with my experience and I still like learning new ways of doing what I had implemented before.
Thus, my tip for you would be to think a simple game or app and try to develop it in order to learn.

Installing Cocos2D is not difficult, just download from the official site, read the instructions contained in the folder and run the instal-templates.sh.
Now, creating a project using this framework is really easy: You just have to choose a Cocos2D template. There are three options:

Which one should you use? It depends on your needs and your programming skills on C or C++:

• The basic "cocos2d": recommended for beginners and for projects without physics. Don't be confused with the name, professional games have been developed with this template.
• Cocos2d with Box2D: the most widely used in projects with physics because it's written in C++. It demands a change of the extension to .mm to all files importing this library. An advantage of this library is that there are a lot of documentation, tutorials, ...
• Cocos2d with Chipmunk: my favorite for projects with physics. It doesn't affect the code and you don't need to change any extension. It's simple, easy and it's written in C.

The main bibliography I've used as reference are:

• The tutorial I mentioned at the beginning of the post
• A digital version of a Cocos2D book

Also, it's very useful to check in the oficial site forum and sometimes at the Apple's web for developers (like this). This last one only as reference. 

But this is just the beginning. The fun starts now...