Question

我有一个带有精灵的应用程序。我要做的是让精灵的起始位置随机。我对'x'坐标没问题，我只想让'y'坐标随机。

在下面的代码中，我设置了一个随机对象，我有一个'y'坐标集，但我不知道如何将这两个坐标结合起来，以便它在一个随机的地方开始。理想情况下，我希望精灵每次离开屏幕时都会在一个随机的地方开始并重新开启，但首先我想让它随机启动：

package cct.mad.lab;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;

import java.util.Random;


public class Sprite {

//x,y position of sprite - initial position (0,50)
private int x = 0; 
private int y = 50;
private int xSpeed = 80;//Horizontal increment of position (speed)
private int ySpeed = 5;// Vertical increment of position (speed)
private GameView gameView;
private Bitmap spritebmp;
//Width and Height of the Sprite image
private int bmp_width;
private int bmp_height;
// Needed for new random coordinates.
private Random random = new Random();



public Sprite(GameView gameView) {
      this.gameView=gameView;
      spritebmp = BitmapFactory.decodeResource(gameView.getResources(),
              R.drawable.sprite_robot);
      this.bmp_width = spritebmp.getWidth();
      this.bmp_height= spritebmp.getHeight();
 }
//update the position of the sprite
public void update() {
    x = x + xSpeed;
    y = y + ySpeed;
    wrapAround(); //Adjust motion of sprite.
}

public void draw(Canvas canvas) {

    //Draw sprite image
    canvas.drawBitmap(spritebmp, x , y, null);
}

public void wrapAround(){
    //Code to wrap around   
    if (x < 0) x = x + gameView.getWidth(); //increment x whilst not off screen
    if (x >= gameView.getWidth()){ //if gone of the right sides of screen
            x = x - gameView.getWidth(); //Reset x
    }
    if (y < 0) y = y + gameView.getHeight();//increment y whilst not off screen
    if (y >= gameView.getHeight()){//if gone of the bottom of screen
        y -= gameView.getHeight();//Reset y
    }
}

}

一如既往，任何帮助都非常感激。

由于

Answer 1

我不确定你的问题究竟在哪里。有一个Random.nextInt(int max)方法，所以您可以执行类似

的操作

public Sprite(GameView gameView) {
      this.gameView=gameView;
      spritebmp = BitmapFactory.decodeResource(gameView.getResources(),
              R.drawable.sprite_robot);
      this.bmp_width = spritebmp.getWidth();
      this.bmp_height= spritebmp.getHeight();

      this.x = random.nextInt(gameView.getWidth());
      this.y = random.nextInt(gameView.getHeight());
}

这是您正在寻找的，还是在其他地方遇到麻烦？

Android App中的随机坐标

1 个答案: