android 游戏 Canvas 常用方法

效果图

public class MySurfaceView extends SurfaceView implements Callback, Runnable {
//用于控制SurfaceView
private SurfaceHolder sfh;
//声明一个画笔
private Paint paint;
//声明一条线程
private Thread th;
//线程消亡的标识位
private boolean flag;
//声明一个画布
private Canvas canvas;
//声明屏幕的宽高
private int screenW, screenH;
//设置画布绘图无锯齿
private PaintFlagsDrawFilter pfd = new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
/**
 * SurfaceView初始化函数
 */
public MySurfaceView(Context context) {
super(context);
//实例SurfaceHolder
        sfh = this.getHolder();
//为SurfaceView添加状态监听
        sfh.addCallback(this);
//实例一个画笔
        paint = new Paint();
//设置画笔颜色为白色
        paint.setColor(Color.WHITE);
//设置焦点
        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) {
//----设置画布绘图无锯齿
            canvas.setDrawFilter(pfd);
//----利用填充画布，刷屏
            canvas.drawColor(Color.BLACK);
//----绘制文本
            canvas.drawText("drawText", 10, 10, paint);
//----绘制像素点
            canvas.drawPoint(10, 20, paint);
//----绘制多个像素点
            canvas.drawPoints(new float[] { 10, 30, 30, 30 }, paint);
//----绘制直线
            canvas.drawLine(10, 40, 50, 40, paint);
//----绘制多条直线
            canvas.drawLines(new float[] { 10, 50, 50, 50, 70, 50, 110, 50 }, paint);
//----绘制矩形
            canvas.drawRect(10, 60, 40, 100, paint);
//----绘制矩形2
            Rect rect = new Rect(10, 110, 60, 130);
            canvas.drawRect(rect, paint);
            canvas.drawRect(rect, paint);
//----绘制圆角矩形
            RectF rectF = new RectF(10, 140, 60, 170);
            canvas.drawRoundRect(rectF, 20, 20, paint);
//----绘制圆形
            canvas.drawCircle(20, 200, 20, paint);
//----绘制弧形
            canvas.drawArc(new RectF(150, 20, 200, 70), 0, 230, true, paint);
//----绘制椭圆
            canvas.drawOval(new RectF(150, 80, 180, 100), paint);
//----绘制指定路径图形
            Path path = new Path();
//设置路径起点
            path.moveTo(160, 150);
//路线1
            path.lineTo(200, 150);
//路线2
            path.lineTo(180, 200);
//路径结束
            path.close();
            canvas.drawPath(path, paint);
//----绘制指定路径图形
            Path pathCircle = new Path();
//添加一个圆形的路径
            pathCircle.addCircle(130, 260, 20, Path.Direction.CCW);
//----绘制带圆形的路径文本
            canvas.drawTextOnPath("PathText", pathCircle, 10, 20, 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;
    }
}