mysurfaceview.java

来自「Android开发精典案例60个」· Java 代码 · 共 148 行

package com.csp;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Bitmap.Config;
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;
	//icon位图
	private Bitmap bmpIcon;
	//截屏的图
	private Bitmap bmpClip;
	//截屏的画布
	private Canvas canvasClip;

	/**
	 * 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();
		//实例Icon位图
		bmpIcon = BitmapFactory.decodeResource(this.getResources(), R.drawable.icon);
		//创建一个与当前屏幕大小相同的图片
		bmpClip = Bitmap.createBitmap(this.getWidth(), this.getHeight(), Config.ARGB_8888);
		//通过创建的图片，得到画布实例
		canvasClip = new Canvas(bmpClip);
		//利用截屏画布刷屏
		canvasClip.drawColor(Color.WHITE);
		//利用截屏画布绘制一张icon图
		canvasClip.drawBitmap(bmpIcon, 0, 0, paint);
		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);
				//绘制icon位图
				canvas.drawBitmap(bmpIcon, 0, 0, paint);
				//绘制截屏的位图
				canvas.drawBitmap(bmpClip, 50, 50, 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) {
		return true;
	}

	/**
	 * 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;
	}
}