Android应用源码之(圆形碰撞).zip项目安卓应用源码下载

package com.cc; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.view.KeyEvent; import android.view.MotionEvent; import android.view.SurfaceHolder; import android.view.SurfaceView; import android.view.SurfaceHolder.Callback; /** * * @author Himi * */ public class MySurfaceView extends SurfaceView implements Callback, Runnable { private SurfaceHolder sfh; private Paint paint; private Thread th; private boolean flag; private Canvas canvas; private int screenW, screenH; //定义两个圆形的半径与坐标 private int r1 = 20, r2 = 20; private int x1 = 50, y1 = 100, x2 = 150, y2 = 100; //定义一个碰撞标识位 private boolean isCollision; /** * SurfaceView初始化函数 */ public MySurfaceView(Context context) { super(context); sfh = this.getHolder(); sfh.addCallback(this); paint = new Paint(); paint.setColor(Color.WHITE); paint.setAntiAlias(true); setFocusable(true); } /** * SurfaceView视图创建，响应此函数 */ @Override public void surfaceCreated(SurfaceHolder holder) { screenW = this.getWidth(); screenH = this.getHeight(); flag = true; //实例线程 th = new Thread(this); //启动线程 th.start(); } /** * 游戏绘图 */ public void myDraw() { try { canvas = sfh.lockCanvas(); if (canvas != null) { canvas.drawColor(Color.BLACK); if (isCollision) { paint.setColor(Color.RED); paint.setTextSize(20); canvas.drawText("Collision!", 0, 30, paint); } else { paint.setColor(Color.WHITE); } canvas.drawCircle(x1, y1, r1, paint); canvas.drawCircle(x2, y2, r2, paint); } } catch (Exception e) { // TODO: handle exception } finally { if (canvas != null) sfh.unlockCanvasAndPost(canvas); } } /** * 触屏事件监听 */ @Override public boolean onTouchEvent(MotionEvent event) { x1 = (int) event.getX(); y1 = (int) event.getY(); if (isCollisionWithCircle(x1, y1, x2, y2, r1, r2)) { isCollision = true; } else { isCollision = false; } return true; } /** * 圆形碰撞 * @param x1 圆形1的圆心X坐标 * @param y1 圆形2的圆心X坐标 * @param x2 圆形1的圆心Y坐标 * @param y2 圆形2的圆心Y坐标 * @param r1 圆形1的半径 * @param r2 圆形2的半径 * @return */ private boolean isCollisionWithCircle(int x1, int y1, int x2, int y2, int r1, int r2) { //Math.sqrt:开平方 //Math.pow(double x, double y): X的Y次方 if (Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(y1 - y2, 2)) <= r1 + r2) { //如果两圆的圆心距小于或等于两圆半径则认为发生碰撞 return true; } return false; } /** * 按键事件监听 */ @Override public boolean onKeyDown(int keyCode, KeyEvent event) { return super.onKeyDown(keyCode, event); } /** * 游戏逻辑 */ private void logic() { } @Override public void run() { while (flag) { long start = System.currentTimeMillis(); myDraw(); logic(); long end = System.currentTimeMillis(); try { if (end - start < 50) { Thread.sleep(50 - (end - start)); } } catch (InterruptedException e) { e.printStackTrace(); } } } /** * SurfaceView视图状态发生改变，响应此函数 */ @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { } /** * SurfaceView视图消亡时，响应此函数 */ @Override public void surfaceDestroyed(SurfaceHolder holder) { flag = false; } }