One background image for all scenes objective c

Question

I have one image for background for all scenes,is it possible to write somewhere code for background so i don't have to write it on every scene I got and if it is then where I need to put it? For now i use this basic code :

    background = [SKSpriteNode spriteNodeWithImageNamed:@"backMenu.png"];
    titleBackground.position = CGPointMake(CGRectGetMidX(self.frame),CGRectGetMidY(self.frame));
    titleBackground.size = self.frame.size;
    titleBackground.zPosition = -10;
    [self addChild:background];

Answer 1

If you have a code which is repeated among scenes, then you can create a BaseScene and put that code there. So, everything shared between scenes , goes into BaseScene.

BaseScene.h:

#import <SpriteKit/SpriteKit.h>

@interface BaseScene : SKScene

@end

BaseScene.m

#import "BaseScene.h"

@interface BaseScene()

@property(nonatomic, strong) SKSpriteNode *background;

@end

@implementation BaseScene


-(void)didMoveToView:(SKView *)view{

    self.background = [SKSpriteNode spriteNodeWithImageNamed:@"backMenu"];
    [self addChild:self.background];

}

@end

GameScene.h (now GameScene inherits from BaseScene, not from the SKScene)

#import <SpriteKit/SpriteKit.h>
#import "BaseScene.h"


@interface GameScene : BaseScene

@end

GameScene.m

#import "GameScene.h"

@implementation GameScene

-(void)didMoveToView:(SKView *)view {
    /* Setup your scene here */

    [super didMoveToView:view];
}
@end

Finally, you call [super didMoveToView:view]; in every subclass of a BaseScene which calls a didMoveToView: of a BaseScene, which in turn adds background node to the current scene.