How do I change the position of the button after initialization?

Question

I have ASViewController<ASDisplayNode>. In init() I set into display node new node with ASAbsoluteLayoutSpec which contains two button. How I can change button position during ASViewController lifecycle?

Answer 1

Of cause, you can. Just use the variable flag or switch statement in layoutThatFits: method for change logic behavior, and after changing a flag state call just self.setNeedsLayout or transitionLayoutWithAnimation:shouldMeasureAsync:measurementCompletion: for animation, and this recommended method for change layouts. For more info read the docs Example:

override func layoutSpecThatFits(_ constrainedSize: ASSizeRange) -> ASLayoutSpec {
let fieldNode: FieldNode

  if self.fieldState == .signupNodeName { // flag dependens state
      fieldNode = self.nameField
  } else {
      fieldNode = self.ageField
  }

  let stack = ASStackLayoutSpec()
  stack.children = [fieldNode, buttonNode]

  let insets = UIEdgeInsets(top: 15, left: 15, bottom: 15, right: 15)
  return ASInsetLayoutSpec(insets: insets, child: stack)
}

for change layouts use transitionLayoutWithAnimation:shouldMeasureAsync:measurementCompletion: method call. Don't forget change a state before of this call.