shapeDrawable

构造方法：
ShapeDrawable();
ShapeDrawable(Shape s);
作用：
在画布上绘画一些简单的图形，并且管理图形的外观。

public class SampleView extends View { 

        private ShapeDrawable mShapeDrawable = null; 

        public SampleView(Context context) { 
                super(context); 
        } 

@Override 
        protected void onDraw(Canvas canvas) { 
                super.onDraw(canvas); 
                //画背景 
                canvas.drawColor(Color.WHITE); 
               //画图形 
                mShapeDrawable = new ShapeDrawable(new OvalShape()); 
               //获得画笔并且绘制图形 
                mShapeDrawable.getPaint().setColor(Color.GREEN); 
               //设置x,y,left,top 
               mShapeDrawable.setBounds(20,60,50,80); 
              //绘制图形 
               mShapeDrawable.draw(canvas); 

       } 
}