游戏角色在屏幕行走
MySurfaceView
package org.wp.activity;import android.content.Context;import android.content.res.Resources;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.util.Log;import android.view.KeyEvent;import android.view.SurfaceHolder;import android.view.SurfaceView;/** * canvas.save() 和 canvas.restore()是两个相互匹配出现的， * 作用是用来保存画布的状态和取出保存的状态的。 * * 这里稍微解释一下， * 当我们对画布进行旋转，缩放，平移等操作的时候其实我们是想对特定的元素进行操作， * 比如图片，一个矩形等，但是当你用canvas的方法来进行这些操作的时候， * 其实是对整个画布进行了操作，那么之后在画布上的元素都会受到影响， * 所以我们在操作之前调用canvas.save()来保存画布当前的状态， * 当操作之后取出之前保存过的状态，这样就不会对其他的元素进行影响 * * 代码段1： * public void draw() { * Canvas canvas = sfh.lockCanvas(); * canvas.drawColor(Color.BLACK); * canvas.drawBitmap(bmp1, 0,0,paint); * canvas.save(); * canvas.scale(1.5f, 1.5f); * canvas.restore(); * canvas.drawBitmap(bmp2, 0,0,paint); * sfh.unlockCanvasAndPost(canvas); * } * * 代码段2： * * public void draw() { * Canvas canvas = sfh.lockCanvas(); * canvas.drawColor(Color.BLACK); * canvas.drawBitmap(bmp1, 0,0,paint); * canvas.scale(1.5f, 1.5f); * canvas.drawBitmap(bmp2, 0,0,paint); * sfh.unlockCanvasAndPost(canvas); * } * * 上面这两个代码片段中我们都假设有两张图片 bmp1和bmp2，并且都画在画布上! * 那么代码段1和代码段2的不同: * * 代码段1中我们进行画布缩放的之前保存了画布状态， * 做了缩放操作之后又取出之前保存的状态， * 这样做是为了保证bmp2正常画出来不受到缩放的影响！ * * 代码段2里，画了bmp1后就执行了缩放操作，并且没有保存状态！ * 紧接着画了bmp2，那么bmp2也会一样受到缩放的影响！！ * * 所以我们如果单独处理一张图片的时候，而且不想影响其他部分的绘制，那么应该如下来做： * * public void draw() { * Canvas canvas = sfh.lockCanvas(); * canvas.drawColor(Color.BLACK); * canvas.drawBitmap(bmp1, 0,0,paint); * canvas.save(); * canvas.scale(1.5f, 1.5f); * canvas.drawBitmap(bmp2, 0,0,paint); * canvas.restore(); * sfh.unlockCanvasAndPost(canvas); * } * * * @author wp * */public class MySurfaceView extends SurfaceView implementsSurfaceHolder.Callback, Runnable {private static final String TAG = "MySurfaceView";private SurfaceHolder sfh;private Resources res;private Bitmap bmp;private Paint p1;private Paint p2;private int SH, SW;private Canvas canvas;private int bmp_x = 100, bmp_y = 100; // 初始坐标位置private boolean UP, DOWN, LEFT, RIGHT; // 按键类型标识private int animation_up[] = { 3, 4, 5 }; // 向上图片位置private int animation_down[] = { 0, 1, 2 }; // 向下图片位置private int animation_left[] = { 6, 7, 8 }; // 向左图片位置private int animation_right[] = { 9, 10, 11 }; // 向右图片位置private int animation_init[] = animation_down; // 默认人物图片向下private int frame_count; // 人物对应数组位置public MySurfaceView(Context context) {super(context);this.setKeepScreenOn(true); // 保持屏幕常亮/* * 此方法是用来响应按键！如果是自己定义一个继承自View的类, * 重新实现onKeyDown方法后,只有当该View获得焦点时才会调用onKeyDown方法, * Actvity中的onKeyDown方法是当所有控件均没有处理该按键事件时,才会调用. */this.setFocusable(true);sfh = this.getHolder();sfh.addCallback(this);res = this.getResources();bmp = BitmapFactory.decodeResource(res, R.drawable.enemy1);p1 = new Paint();p1.setColor(Color.YELLOW);p1.setAntiAlias(true);p2 = new Paint();p2.setColor(Color.RED);p2.setAntiAlias(true);}@Overridepublic void surfaceCreated(SurfaceHolder holder) {Log.i(TAG, "surfaceCreated()");SW = this.getWidth();SH = this.getHeight();Log.i(TAG, "SW：" + SW + " SH：" + SH);new Thread(this).start();}@Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {Log.i(TAG, "surfaceChanged()");}@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {Log.i(TAG, "surfaceDestroyed()");}@Overridepublic void run() {while (true) {draw();cycle();try {Thread.sleep(100);} catch (Exception e) {e.printStackTrace();}}}private void draw() {Log.i(TAG, "draw()");canvas = sfh.lockCanvas();/* * 这里也是对屏幕进行刷屏操作，其实这也只是一种， * 如果用到drawRGB的方法同样实现，当然也可以用fillRect等来刷屏。 * 在继承view中，因为onDraw方法是系统自动调用的， * 不像在surfaceview这里这样去在run里面自己去不断调用， * 在view中我们可以使用invalidate()/postInvalidate() * 这两种方法实现让系统调用onDraw方法，这里也是和surfaceview中的不同之一！ */canvas.drawRect(0, 0, SW, SH, p1);canvas.save();canvas.drawText("wp", bmp_x - 1, bmp_y - 10, p2); // 图片上方人物名称canvas.clipRect(bmp_x, bmp_y, bmp_x + bmp.getWidth() / 13, bmp_y + bmp.getHeight()); // 裁剪图片人物if (animation_init == animation_up) {canvas.drawBitmap(bmp, bmp_x - animation_up[frame_count] * (bmp.getWidth() / 13), bmp_y, p1);} else if (animation_init == animation_down) {canvas.drawBitmap(bmp, bmp_x - animation_down[frame_count] * (bmp.getWidth() / 13), bmp_y, p1);} else if (animation_init == animation_left) {canvas.drawBitmap(bmp, bmp_x - animation_left[frame_count] * (bmp.getWidth() / 13), bmp_y, p1);} else if (animation_init == animation_right) {canvas.drawBitmap(bmp, bmp_x - animation_right[frame_count] * (bmp.getWidth() / 13), bmp_y, p1);}canvas.restore();sfh.unlockCanvasAndPost(canvas);}private void cycle() {Log.i(TAG, "cycle()");if (DOWN) {bmp_y += 5;} else if (UP) {bmp_y -= 5;} else if (LEFT) {bmp_x -= 5;} else if (RIGHT) {bmp_x += 5;}// 按键的行为发生，循环图片位置if (UP || DOWN || LEFT || RIGHT) {if (frame_count < 2) {frame_count++;} else {frame_count = 0;}}// 用户松开按键，恢复图片位置if (UP == false && DOWN == false && LEFT == false && RIGHT == false) {frame_count = 0;}}@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {if (keyCode == KeyEvent.KEYCODE_DPAD_UP) {if (UP == false) {animation_init = animation_up;}UP = true;} else if (keyCode == KeyEvent.KEYCODE_DPAD_DOWN) {if (DOWN == false) {animation_init = animation_down;}DOWN = true;} else if (keyCode == KeyEvent.KEYCODE_DPAD_LEFT) {if (LEFT == false) {animation_init = animation_left;}LEFT = true;} else if (keyCode == KeyEvent.KEYCODE_DPAD_RIGHT) {if (RIGHT == false) {animation_init = animation_right;}RIGHT = true;}return super.onKeyDown(keyCode, event);}@Overridepublic boolean onKeyUp(int keyCode, KeyEvent event) {if (UP) {UP = false;} else if (DOWN) {DOWN = false;} else if (LEFT) {LEFT = false;} else if (RIGHT) {RIGHT = false;}return super.onKeyUp(keyCode, event);}}?
?
?