no visible #interface for 'Player' declares the selector 'walkRight' - ios

Question

// Player.m
#import "Player.h"
#implementation Player
+(id)player{
Player *player = [Player spriteNodeWithColor:[UIColor brownColor] size:CGSizeMake(32, 32)];
player.name = #"player";
player.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:player.size];
return player;
}
- (void)walkRight {
SKAction *incRight = [SKAction moveByX:10 y:0 duration:0];
[self runAction:incRight];
}
#end
// MyScene.h
#import "MyScene.h"
#import "Player.h"
#implementation MyScene
-(id)initWithSize:(CGSize)size {
if (self = [super initWithSize:size]) {
/* Setup your scene here */
self.anchorPoint = CGPointMake(0.5, 0.5);
self.backgroundColor = [SKColor colorWithRed:0.15 green:0.15 blue:0.3 alpha:1.0];
SKSpriteNode *ground = [SKSpriteNode spriteNodeWithColor:[UIColor greenColor] size:CGSizeMake(self.frame.size.width, 30)];
ground.position = CGPointMake(0, -self.frame.size.height/2 + ground.frame.size.height/2);
ground.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:ground.size];
ground.physicsBody.dynamic = NO;
[self addChild:ground];
Player *player = [Player player];
[self addChild:player];
}
return self;
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
Player *player = (Player *)[self childNodeWithName:#"player"];
[player walkRight];
}
-(void)update:(CFTimeInterval)currentTime {
/* Called before each frame is rendered */
}
#end
I'm quite new to objective-c. Well I tried to build the above code and got the error "no visible #interface for 'Player' declares the selector 'walkRight'"
I really do not know why. I would really appreciate it if someone could help me. Thank you.

Answer 1

Make sure you've declared the walkRight method in your Player.h file. This should go somewhere after your interface declaration in that file:
-(void)walkRight;
That allows other files that import Player.h to know that Player.m implements the walkRight method.

Answer 2

Change your player method to return instancetype instead of id. This will make the warning go away. Also declare the walkRight method in the header (.h) file of your Player class.
+(instancetype)player{
Player *player = [Player spriteNodeWithColor:[UIColor brownColor] size:CGSizeMake(32, 32)];
....
return player;
}
Read more about instancetype here and here.
Hope that helps!