CODEWITHSUNDEEP
iosobjective-cswiftsprite-kit
Squid
Squid

Reputation: 315

How do you determine if a spritenode is not equal to nil?

So in Obj-C I used to do it like this:

SKSpriteNode *someNode = [SKSpriteNode spriteNodeWithImageNamed:@"foo"];
someNode.position = CGPointMake(100,100);
someNode.size = CGSizeMake(100,100);
[self addChild:someNode]

//I'd test it like this:
if (someNode) {
  //Do something
}

//I could also do it like this:
if (someNode != nil) {
   //Do something
}

However, when I want to achieve the same thing in swift, it gives me the error: Binary operator '!=' cannot be applied to operands of type 'SKSpriteNode' and 'nil'

I did it like this:

if someNode != nil {
  //Do something
}

I also tried this:

if someNode {
  //Do something
}

This gives me the error: Type 'SKSpriteNode' does not conform to protocol 'BooleanType'

Is there a way to test if a node already exists?

Upvotes: 4

Views: 1179

Answers (1)

Alessandro Ornano
Alessandro Ornano

Reputation: 35392

Basically you have to consider that SKSpriteNode node derive from SKNode, so it inherits all its properties according to Apple doc SKNode Class Reference:

In Swift 2.x the best general way to do is:

if let someNodeExist = self.childNodeWithName("\\someNode") {
        print("\(someNodeExist.debugDescription)")
    }

In Swift 3.x:

if let someNodeExist = self.childNode(withName: "\\someNode") {
        print("\(someNodeExist.debugDescription)")
}

or using guard:

guard let someNodeExist = self.childNode(withName: "\\someNode") else { return }

After that you can check which kind of class is someNodeExist or casting directly to SKSpriteNode, you decide.

Upvotes: 2

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