How can I make a functioning animated button? - ios

Question

I have a button set up in a scene like this:
self.playButton = [SKSpriteNode spriteWithImageNamed:#"playbutton.png"];
self.playButton.size = CGSizeMake(100,100);
self.playButton.position = CGPointMake(CGRectGetMidX(self.frame), 100);
[self addChild:self.playButton];
Then in touchesBegan:
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
if([self.playButton containsPoint:location]){
self.playButton.texture = [SKTexture textureWithImageNamed:#"playbuttonpressed.png"];
[self.playButton runAction: [self touchButtonAction]];
}
Then in touchesEnded:
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
if([self.playButton containsPoint:location]){
self.playButton.texture = [SKTexture textureWithImageNamed:#"playbutton.png"];
[self.view presentScene:self.nextScene transition:self.sceneTransition];
}
Then in touchButtonAction:
SKAction *toSmall = [SKAction scaleBy:0.8 duration:0.1];
return toSmall;
Here's the problem: When I tap the button, touchesEnded gets called before the action is finished, which causes for an incomplete animation which doesn't look good (it seems laggy). How can I make a button that finishes the animation before transitioning?

Answer 1

There are a couple of ways of accomplishing what you want. One of those is using blocks.
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
if([self.playButton containsPoint:location]){
SKAction *block0 = [SKAction runBlock:^{
self.playButton.texture = [SKTexture textureWithImageNamed:#"playbuttonpressed.png"];
[self.playButton runAction: [self touchButtonAction]];
}];
SKAction *wait0 = [SKAction waitForDuration:1.0]; // <- however long it takes for the animation to complete
SKAction *block1 = [SKAction runBlock:^{
self.playButton.texture = [SKTexture textureWithImageNamed:#"playbutton.png"];
[self.view presentScene:self.nextScene transaction:self.sceneTransaction];
}];
[self runAction:[SKAction sequence:#[block0, wait0, block1]]];
}
For more information on using blocks, you can read the Apple Blocks Programming Guide.