How to add particle effects to an iOS App that is not a game using iOS 7 SpriteKit Particle?

Question

I need to add a rain particle effect to my app, I have been having a tough time finding ways to actually execute this idea.

I tried following this CALayer approach

Answer 1

Create a SKScene in your UIView to add a SKEmitterNode particle effect.

One way of doing this:

1.In storyboard (or programatically if you prefer) add a View object on top of the existing View and resize it to your needs.
2.Change the class of the new view to SKView
3.In your view controller .h file create a property for the SKView:

@property IBOutlet SKView *skView;

4.Link the SKView on your storyboard to the skView property.
5.Create a new class, subclassing SKScene. MyScene.h will look like:

#import <SpriteKit/SpriteKit.h>
@interface MyScene : SKScene
@end

MyScene.m below contains code to create a particle effect whenever and wherever the SKView is touched.

#import "MyScene.h"

@implementation MyScene

-(id)initWithSize:(CGSize)size {    
    if (self = [super initWithSize:size]) {
        /* Setup your scene here */

        self.backgroundColor = [SKColor colorWithRed:0.15 green:0.15 blue:0.3 alpha:1.0];
        SKLabelNode *myLabel = [SKLabelNode labelNodeWithFontNamed:@"Chalkduster"];
        myLabel.text = @"Hello, World!";
        myLabel.fontSize = 30;
        myLabel.position = CGPointMake(CGRectGetMidX(self.frame),
                                   CGRectGetMidY(self.frame));

        [self addChild:myLabel];
    }
    return self;
}

//particle explosion - uses MyParticle.sks
- (SKEmitterNode *) newExplosion: (float)posX : (float) posy
{
    SKEmitterNode *emitter =  [NSKeyedUnarchiver unarchiveObjectWithFile:[[NSBundle mainBundle] pathForResource:@"MyParticle" ofType:@"sks"]];
    emitter.position = CGPointMake(posX,posy);
    emitter.name = @"explosion";
    emitter.targetNode = self.scene;
    emitter.numParticlesToEmit = 1000;
    emitter.zPosition=2.0;
    return emitter;
}

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    /* Called when a touch begins */

    for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];
        //add effect at touch location
        [self addChild:[self newExplosion:location.x : location.y]];
    }
}

-(void)update:(CFTimeInterval)currentTime {
    /* Called before each frame is rendered */
}

@end

6.In your main view controller, include your scene class:

#import "MyScene.h"

and add code to viewDidLoad to initialise the SKView:

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Configure the SKView
    SKView * skView = _skView;
    skView.showsFPS = YES;
    skView.showsNodeCount = YES;

    // Create and configure the scene.
    SKScene * scene = [MyScene sceneWithSize:skView.bounds.size];
    scene.scaleMode = SKSceneScaleModeAspectFill;

    // Present the scene.
    [skView presentScene:scene];
}

You should then have a working SKScene within your main UIView.