gistfile1.txt

package;

import openfl.display.Sprite;
import openfl.Lib;
import openfl.events.Event;

class Main extends Sprite {
  private var _sprites: Array<Sprite> = [];
  private var _previousTime: Int = 0;
  
  public function new() {
    super();
    
    if (Lib.current.stage != null) {
      init();
    } else {
      addEventListener(Event.ADDED_TO_STAGE, handleAddedToStageEvent);
    }
  }
  
  //
  
  private function init() {
    stage.frameRate = 60;
    
    addSprites();
    addEventListeners();
  }
  
  private function addSprites() {
    var radius = 50.0;
    
    for (spriteIndex in 0 ... 5) {
      var circleSprite = getCircleSprite(radius);
      
      circleSprite.y = spriteIndex * radius;
      
      stage.addChild(circleSprite);
      
      _sprites.push(circleSprite);
    }
  }
  
  private function addEventListeners() {
    addEventListener(Event.ENTER_FRAME, handleEnterFrameEvent);
  }
  
  private function getCircleSprite(radius: Float): Sprite {
    var circleSprite = new Sprite();
    
    circleSprite.graphics.beginFill(0xC0C0C0);
    circleSprite.graphics.drawEllipse(0.0, 0.0, radius, radius);
    circleSprite.graphics.endFill();
    
    return circleSprite;
  }
  
  private function moveSprites(secondsSinceLastFrame: Float) {
    var speed = 20.0;
    
    for (sprite in _sprites) {
      sprite.x += speed * secondsSinceLastFrame;
    }
  }
  
  // event handlers
  
  private function handleAddedToStageEvent(event: Event) {
    removeEventListener(Event.ADDED_TO_STAGE, handleAddedToStageEvent);
    init();
  }
  
  private function handleEnterFrameEvent(event: Event) {
    var currentTime = Lib.getTimer();
    var deltaTime = currentTime - _previousTime;
    
    _previousTime = currentTime;
    
    var secondsSinceLastFrame = deltaTime / 1000;
    
    moveSprites(secondsSinceLastFrame);
  }
}