Android SurfaceView绘制组合图形

た入场券 2022-08-05 04:17 186阅读 0赞

学习SurfaceView绘制组合图形的一个案例：

1.首先创建一个容器Contanier：

public class Contanier \{  
private List<Contanier> children = null;  
private float x = 0, y = 0;  
  
public Contanier() \{  
children = new ArrayList<Contanier>();  
\}  
  
public void draw(Canvas canvas) \{  
canvas.save();  
canvas.translate(getX(), getY());  
ChildrenView(canvas);  
for (Contanier c : children) \{  
c.draw(canvas);  
\}  
canvas.restore();  
\}  
  
public void ChildrenView(Canvas canvas) \{  
\}  
  
public void addChildrenView(Contanier child) \{  
children.add(child);  
\}  
  
  
public void removeChildrenView(Contanier child) \{  
children.remove(child);  
\}  
  
public float getX() \{  
return x;  
\}  
  
public void setX(float x) \{  
this.x = x;  
\}  
  
public float getY() \{  
return y;  
\}  
  
public void setY(float y) \{  
this.y = y;  
\}  
  
  \}

2.创建要组合的两个子图形Rect和Circle

public class Rect extends Contanier \{  
private Paint paint = null;  
  
public Rect() \{  
paint = new Paint();  
paint.setColor(Color.BLUE);  
\}  
  
@Override  
public void ChildrenView(Canvas canvas) \{  
super.ChildrenView(canvas);  
canvas.drawRect(0, 0, 100, 100, paint);  
this.setX(this.getX() + 1);  
\}  
  \}

public class Circle extends Contanier \{  
  
  
private Paint paint = null;  
  
  
public Circle() \{  
paint = new Paint();  
paint.setColor(Color.RED);  
\}  
  
  
@Override  
public void ChildrenView(Canvas canvas) \{  
super.ChildrenView(canvas);  
canvas.drawCircle(50, 50, 50, paint);  
\}  
  \}

3.创建一个类并继承SurfaceView实现Callback接口

public class MyView extends SurfaceView implements Callback \{  
private Contanier contanier;  
private Rect rect;  
private Circle circle;  
private Timer timer = null;  
private TimerTask timerTask = null;  
  
public MyView(Context context) \{  
super(context);  
contanier = new Contanier();  
rect = new Rect();  
circle = new Circle();  
rect.addChildrenView(circle);  
contanier.addChildrenView(rect);  
getHolder().addCallback(this);  
\}  
  
public void draw() \{  
Canvas canvas = getHolder().lockCanvas();  
canvas.drawColor(Color.WHITE);  
contanier.draw(canvas);  
getHolder().unlockCanvasAndPost(canvas);  
\}  
  
public void startTimer() \{  
timer = new Timer();  
timerTask = new TimerTask() \{  
@Override  
public void run() \{  
draw();  
\}  
\};  
timer.schedule(timerTask, 100, 100);  
\}  
  
public void stopTimer() \{  
if (timer != null) \{  
timer.cancel();  
timer = null;  
\}  
\}  
  
@Override  
public void surfaceCreated(SurfaceHolder holder) \{  
startTimer();  
\}  
  
@Override  
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) \{  
\}  
  
@Override  
public void surfaceDestroyed(SurfaceHolder holder) \{  
stopTimer();  
\}  
  
  \}

4.mainActivity中使用：

public class MainActivity extends Activity \{  
@Override  
protected void onCreate(Bundle savedInstanceState) \{  
super.onCreate(savedInstanceState);  
setContentView(new MyView(this));  
\}  
  
  \}

Demo地址：http://download.csdn.net/detail/qq\_26323183/8772439