安卓等边三角形

public class Mytest extends View
{
public Mytest(Context context, AttributeSet set)
{
super(context,set);
}
protected void onDraw(Canvas canvas){
super.onDraw(canvas);
Paint paint=new Paint();
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.BLUE);
int viewwid=this.getWidth();
float line=(float)java.lang.Math.sqrt(viewwid*viewwid-viewwid/2*viewwid/2);//等边三角形中间的直线
float[] pts={
viewwid/2,0,viewwid,line,//1
viewwid,line,0,line,//2
0,line,viewwid/2,0,//3
viewwid/2,0,viewwid/2,line,//中线
0,line,viewwid/4*3,line/2,//中线
viewwid,line,viewwid/4,line/2//中线
};
canvas.drawLines(pts,paint);
canvas.drawCircle(viewwid/2,line/3*2,line/3,paint);//圆
}}