android绘制实心。空心五角星

package com.example.test;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.View;
/**
*
* 假设五角星外接圆半径为1,有一个角朝上,以五角星中心为原点:

外点
x=Rcos(72°*k) y=Rsin(72°*k) k=0,1,2,3,4

内点
r=Rsin(18)/sin(180-36-18)
x=rcos(72°*k+36°) y=rsin(72°*k+36°) k=0,1,2,3,4

* @author Young
*
*/
public class FiveView2 extends View {

public FiveView2(Context context) {
super(context);
// TODO Auto-generated constructor stub
}

public FiveView2(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

public FiveView2(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
// TODO Auto-generated constructor stub
}

@SuppressLint("NewApi")
public FiveView2(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
// TODO Auto-generated constructor stub
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width=getWidth();
int r=width/2;

float outR=getWidth()/2 /5;
float inR=outR*sin(18)/sin(180-36-18);
Paint paint=new Paint();
paint.setAntiAlias(true);
paint.setColor(Color.YELLOW);
paint.setStrokeWidth(5);

canvas.translate(r/5, r );
canvas.rotate(-18);
Path path = getCompletePath(outR, inR);
paint.setStyle(Style.STROKE);
canvas.drawPath(path, paint);
path = getHalfPath(outR, inR);
paint.setStyle(Style.FILL);
canvas.drawPath(path, paint);

canvas.rotate(18);
canvas.translate(r/5*2+15,0 );
canvas.rotate(-18);
path = getCompletePath(outR, inR);
paint.setStyle(Style.STROKE);
canvas.drawPath(path, paint);
paint.setStyle(Style.FILL);
canvas.drawPath(path, paint);

canvas.rotate(18);
canvas.translate(r/5*2+15,0 );
canvas.rotate(-18);
path = getCompletePath(outR, inR);
paint.setStyle(Style.STROKE);
canvas.drawPath(path, paint);

canvas.rotate(18);
canvas.translate(r/5*2+15,0 );
canvas.rotate(-18);
path = getHalfPath(outR, inR);
paint.setStyle(Style.STROKE);
canvas.drawPath(path, paint);

canvas.rotate(18);
canvas.translate(r/5*2+15,0 );
canvas.rotate(-18);
path = getHalfPath(outR, inR);
paint.setStyle(Style.STROKE);
canvas.drawPath(path, paint);
paint.setStyle(Style.FILL);
canvas.drawPath(path, paint);

}

private Path getHalfPath(float outR, float inR) {
Path path;
path=new Path();

path.moveTo(outR*cos(72*4), outR*sin(72*4));

path.lineTo(inR*cos(72*1+36), inR*sin(72*1+36));
path.lineTo(outR*cos(72*2), outR*sin(72*2));
path.lineTo(inR*cos(72*2+36), inR*sin(72*2+36));
path.lineTo(outR*cos(72*3), outR*sin(72*3));
path.lineTo(inR*cos(72*3+36), inR*sin(72*3+36));

path.close();
return path;
}

private Path getCompletePath(float outR, float inR) {
Path path=new Path();

path.moveTo(outR*cos(72*0), outR*sin(72*0));

path.moveTo(outR*cos(72*0), outR*sin(72*0));
path.lineTo(inR*cos(72*0+36), inR*sin(72*0+36));
path.lineTo(outR*cos(72*1), outR*sin(72*1));
path.lineTo(inR*cos(72*1+36), inR*sin(72*1+36));
path.lineTo(outR*cos(72*2), outR*sin(72*2));
path.lineTo(inR*cos(72*2+36), inR*sin(72*2+36));
path.lineTo(outR*cos(72*3), outR*sin(72*3));
path.lineTo(inR*cos(72*3+36), inR*sin(72*3+36));
path.lineTo(outR*cos(72*4), outR*sin(72*4));
path.lineTo(inR*cos(72*4+36), inR*sin(72*4+36));
path.close();
return path;
}

float cos(int num){
return (float) Math.cos(num*Math.PI/180);
}

float sin(int num){
return (float) Math.sin(num*Math.PI/180);
}
}