public class StudyB2Contact extends B2Base { public function StudyB2Contact() { makeB2Walls(); makeGroup(); this.addEventListener(Event.ENTER_FRAME, update, false, 0, true); //マウスジョイント用 this.addEventListener(MouseEvent.MOUSE_DOWN, this.onMouseDown, false, 0, true); this.addEventListener(MouseEvent.MOUSE_UP, this.onMouseUp, false, 0, true); } //Box2D 上下左右の壁作成 private function makeB2Walls():void { /