Android UI SurfaceView的使用-绘制单个图型或多个图形

新建MyView类继承自SurfaceView:

public class MyView extends SurfaceView implements SurfaceHolder.Callback {

	private Paint paint;

	public MyView(Context context) {

		super(context);

		paint=new Paint();

		paint.setColor(Color.RED);

		getHolder().addCallback(this);

	}

	public void draw(){

		//绘制画布前锁定画布

		Canvas canvas=getHolder().lockCanvas();

		canvas.drawColor(Color.WHITE);

		//从画布的50x50开始绘制，绘制到100x100,绘制面积50x50

		canvas.drawRect(50, 50, 100, 100, paint);

		//将第一条线顺时针旋转90度

		canvas.save(); //将画布处可编辑状态

		canvas.rotate(90,getWidth()/2,getHeight()/2); //按中心点进行旋转

		canvas.drawLine(0, getHeight()/2, getWidth(), getHeight(), paint);

		canvas.restore();// 将画布复原

		canvas.drawLine(0, getHeight()/2+100, getWidth(), getHeight()+100, paint);

		//绘制画布结束后解锁画布

		getHolder().unlockCanvasAndPost(canvas);

	}

	@Override

	public void surfaceChanged(SurfaceHolder holder, int format, int width,

			int height) {

	}

	@Override

	public void surfaceCreated(SurfaceHolder holder) {

		draw();

	}

	@Override

	public void surfaceDestroyed(SurfaceHolder holder) {

	}

MainActivity:

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(new MyView(this));

    }

效果：

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