egret基础-拖拽检测与图片变换
class Move extends egret.Sprite {
private static shared: Move;
public static getInstance() {
if (!Move.shared) {
Move.shared = new Move();
}
return Move.shared;
}
public constructor() {
super();
this.drawGrid();
}
private offsetX: number;
private offsetY: number;
private circle: egret.Shape;
private areaPic: egret.Bitmap;
private drawGrid() {
this.addPicArea()
//画一个红色的圆
this.circle = new egret.Shape();
this.circle.graphics.beginFill(0xff0000);
this.circle.graphics.drawCircle(25, 25, 25);
this.circle.graphics.endFill();
this.addChild(this.circle);
//手指按到屏幕，触发 startMove 方法
this.circle.touchEnabled = true;
this.circle.addEventListener(egret.TouchEvent.TOUCH_BEGIN, this.startMove, this);
//手指离开屏幕，触发 stopMove 方法
this.circle.addEventListener(egret.TouchEvent.TOUCH_END, this.stopMove, this);
}
private startMove(e: egret.TouchEvent): void {
//计算手指和圆形的距离
this.offsetX = e.stageX - this.circle.x;
this.offsetY = e.stageY - this.circle.y;
//手指在屏幕上移动，会触发 onMove 方法
this.stage.addEventListener(egret.TouchEvent.TOUCH_MOVE, this.onMove, this);
}
private stopMove(e: egret.TouchEvent) {
// console.log(e, e.target, 222);
let ax1 = this.areaPic.x;
let ax2 = this.areaPic.x + this.areaPic.width;
let ay1 = this.areaPic.y;
let ay2 = this.areaPic.y + this.areaPic.height;
if (e.target.x > ax1 && e.target.x < ax2 && e.target.y > ay1 && e.target.y < ay2) { console.log('在容器内') } else { console.log('不在容器') } //手指离开屏幕，移除手指移动的监听 this.stage.removeEventListener(egret.TouchEvent.TOUCH_MOVE, this.onMove, this); } private onMove(e: egret.TouchEvent): void { //通过计算手指在屏幕上的位置，计算当前对象的坐标，达到跟随手指移动的效果 this.circle.x = e.stageX - this.offsetX; this.circle.y = e.stageY - this.offsetY; } private addPicArea() { this.areaPic = this.createBitmapByName('egret_icon_png'); this.areaPic.x = 300; this.areaPic.y = 400 this.addChild(this.areaPic); } private createBitmapByName(name: string): egret.Bitmap { let result = new egret.Bitmap(); let texture: egret.Texture = RES.getRes(name); result.texture = texture; return result; } }
this.addChild( Move.getInstance() );