public class MyViewFive extends View {
    private static final String TAG = "MyViewFive";
    private int count = 6;
    private float angle = (float) (Math.PI * 2 / count);
    private float radius;//网格最大半径
    private int centerX;//中心x
    private int centerY;//中心y
    private String[] titles = {"a", "b", "c", "d", "e", "f"};
    private double[] data = {100, 60, 90, 30, 100, 50, 10, 20}; //各维度分值
    private float maxValue = 100;//数据最大值
    private Paint mainPaint;//雷达区画笔
    private Paint valuePaint;//数据区画笔
    private Paint textPaint;//文本画笔
    public MyViewFive(Context context) {
        super(context);
        init();
    }
    public MyViewFive(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        init();
    }
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        radius = Math.min(w, h) / 2 * 0.9f;
        centerX = w / 2;
        centerY = h / 2;
        postInvalidate();
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        drawPolygon(canvas);
        drawLines(canvas);
        drawText(canvas);
        drawValue(canvas);
    }
    private void init(){
        mainPaint=new Paint();
        mainPaint.setColor(Color.BLACK);
        mainPaint.setStyle(Paint.Style.STROKE);
        mainPaint.setStrokeWidth(3f);
        textPaint=new Paint();
        textPaint.setColor(Color.BLUE);
        textPaint.setTextSize(50f);
        valuePaint=new Paint();
        valuePaint.setStyle(Paint.Style.FILL_AND_STROKE);
        valuePaint.setColor(Color.BLUE);
    }
    private void drawPolygon(Canvas canvas){
        Path path = new Path();
        float r = radius / (count - 1);//r是蜘蛛丝之间的间距
        for (int i = 1; i < count; i++) {//中心点不用绘制
            float curR = r * i;//当前半径
            path.reset();
            for (int j = 0; j < count; j++) {
                if (j == 0) {
                    path.moveTo(centerX + curR, centerY);
                } else {
                    //根据半径，计算出蜘蛛丝上每个点的坐标
                    float x = (float) (centerX + curR * Math.cos(angle * j));
                    float y = (float) (centerY + curR * Math.sin(angle * j));
                    path.lineTo(x, y);
                }
            }
            path.close();//闭合路径
            canvas.drawPath(path, mainPaint);
        }
    }
    private void drawLines(Canvas canvas){
        Path path=new Path();
        for (int i = 0; i < count; i++) {
            path.reset();
            path.moveTo(centerX,centerY);
            float x= (float) (centerX+radius*Math.cos(angle*i));
            float y= (float) (centerY+radius*Math.sin(angle*i));
            path.lineTo(x,y);
            canvas.drawPath(path,mainPaint);
        }
    }
    private void drawText(Canvas canvas) {
        Paint.FontMetrics fontMetrics = textPaint.getFontMetrics();
        float fontHeight = fontMetrics.descent - fontMetrics.ascent;
        for (int i = 0; i < count; i++) {
            float x = (float) (centerX + (radius + fontHeight / 2) * Math.cos(angle * i));
            float y = (float) (centerY + (radius + fontHeight / 2) * Math.sin(angle * i));
            canvas.drawText(titles[i], x , y, textPaint);
        }
    }
    private void drawValue(Canvas canvas){
        Path path=new Path();
        valuePaint.setAlpha(245);
        for (int i = 0; i < count; i++) {
            double percentage=data[i]/maxValue;
            float x= (float) (centerX+radius*Math.cos(angle*i)*percentage);
            float y= (float) (centerY+radius*Math.sin(angle*i)*percentage);
            if (i==0){
                path.moveTo(x,y);
            }else {
                path.lineTo(x,y);
            }
            canvas.drawCircle(x,y,10,valuePaint);
        }
        valuePaint.setStyle(Paint.Style.STROKE);
        canvas.drawPath(path,valuePaint);
        valuePaint.setAlpha(170);
        valuePaint.setStyle(Paint.Style.FILL_AND_STROKE);
        canvas.drawPath(path,valuePaint);
    }
}
public class MyViewFive extends View {
    private static final String TAG = "MyViewFive";
    private int count = 6;
    private float angle = (float) (Math.PI * 2 / count);
    private float radius;//网格最大半径
    private int centerX;//中心x
    private int centerY;//中心y
    private String[] titles = {"a", "b", "c", "d", "e", "f"};
    private double[] data = {100, 60, 90, 30, 100, 50, 10, 20}; //各维度分值
    private float maxValue = 100;//数据最大值
    private Paint mainPaint;//雷达区画笔
    private Paint valuePaint;//数据区画笔
    private Paint textPaint;//文本画笔
    public MyViewFive(Context context) {
        super(context);
        init();
    }
    public MyViewFive(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        init();
    }
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        radius = Math.min(w, h) / 2 * 0.9f;
        centerX = w / 2;
        centerY = h / 2;
        postInvalidate();
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        drawPolygon(canvas);
        drawLines(canvas);
        drawText(canvas);
        drawValue(canvas);
    }
    private void init(){
        mainPaint=new Paint();
        mainPaint.setColor(Color.BLACK);
        mainPaint.setStyle(Paint.Style.STROKE);
        mainPaint.setStrokeWidth(3f);
        textPaint=new Paint();
        textPaint.setColor(Color.BLUE);
        textPaint.setTextSize(50f);
        valuePaint=new Paint();
        valuePaint.setStyle(Paint.Style.FILL_AND_STROKE);
        valuePaint.setColor(Color.BLUE);
    }
    private void drawPolygon(Canvas canvas){
        Path path = new Path();
        float r = radius / (count - 1);//r是蜘蛛丝之间的间距
        for (int i = 1; i < count; i++) {//中心点不用绘制
            float curR = r * i;//当前半径
            path.reset();
            for (int j = 0; j < count; j++) {
                if (j == 0) {
                    path.moveTo(centerX + curR, centerY);
                } else {
                    //根据半径，计算出蜘蛛丝上每个点的坐标
                    float x = (float) (centerX + curR * Math.cos(angle * j));
                    float y = (float) (centerY + curR * Math.sin(angle * j));
                    path.lineTo(x, y);
                }
            }
            path.close();//闭合路径
            canvas.drawPath(path, mainPaint);
        }
    }
    private void drawLines(Canvas canvas){
        Path path=new Path();
        for (int i = 0; i < count; i++) {
            path.reset();
            path.moveTo(centerX,centerY);
            float x= (float) (centerX+radius*Math.cos(angle*i));
            float y= (float) (centerY+radius*Math.sin(angle*i));
            path.lineTo(x,y);
            canvas.drawPath(path,mainPaint);
        }
    }
    private void drawText(Canvas canvas) {
        Paint.FontMetrics fontMetrics = textPaint.getFontMetrics();
        float fontHeight = fontMetrics.descent - fontMetrics.ascent;
        for (int i = 0; i < count; i++) {
            float x = (float) (centerX + (radius + fontHeight / 2) * Math.cos(angle * i));
            float y = (float) (centerY + (radius + fontHeight / 2) * Math.sin(angle * i));
            canvas.drawText(titles[i], x , y, textPaint);
        }
    }
    private void drawValue(Canvas canvas){
        Path path=new Path();
        valuePaint.setAlpha(245);
        for (int i = 0; i < count; i++) {
            double percentage=data[i]/maxValue;
            float x= (float) (centerX+radius*Math.cos(angle*i)*percentage);
            float y= (float) (centerY+radius*Math.sin(angle*i)*percentage);
            if (i==0){
                path.moveTo(x,y);
            }else {
                path.lineTo(x,y);
            }
            canvas.drawCircle(x,y,10,valuePaint);
        }
        valuePaint.setStyle(Paint.Style.STROKE);
        canvas.drawPath(path,valuePaint);
        valuePaint.setAlpha(170);
        valuePaint.setStyle(Paint.Style.FILL_AND_STROKE);
        canvas.drawPath(path,valuePaint);
    }
}