ctor(step) {
    // initialize properties that may be required in init
    this.bgSpriteFriendly = new BaseSprite(RSX.battlelog_entry_frame_friendly.img);
    this.bgSpriteFriendly.setVisible(false);
    this.bgSpriteEnemy = new BaseSprite(RSX.battlelog_entry_frame_enemy.img);
    this.bgSpriteEnemy.setVisible(false);
    const contentSize = cc.size(CONFIG.BATTLELOG_ENTRY_SIZE, CONFIG.BATTLELOG_ENTRY_SIZE);

    // do super ctor
    this._super();

    // set anchor
    this.setAnchorPoint(0.5, 0.5);

    // set content size
    // this must be done after the cocos/super ctor
    this.setContentSize(contentSize);
    const centerPosition = this.getCenterPosition();

    // add bg
    this.bgSpriteFriendly.setPosition(centerPosition);
    this.bgSpriteEnemy.setPosition(centerPosition);
    this.addChild(this.bgSpriteFriendly);
    this.addChild(this.bgSpriteEnemy);

    // set step
    this.setStep(step);
  }
************************************************************************
 BattleLogNode
 var BattleLogNode = SdkNode
 BattleLogNode.create()
 - node used to display battle log entries
*************************************************************************