package myapplication.com.myapp.view;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.graphics.RectF;

import android.util.AttributeSet;

import android.view.View;

import java.util.ArrayList;

import myapplication.com.myapp.bean.ViewData;

/**

 * Created by Administrator on 2017/1/8.

 */

public class MyView extends View {

    private int[] mColors = {

            Color.BLUE, Color.DKGRAY, Color.CYAN, Color.RED, Color.GREEN

    };

    private Paint paint;    //画笔

    private ArrayList<ViewData> viewDatas;    //数据集

    private int w;          //View宽高

    private int h;

    private RectF rectF;    //矩形

    public MyView(Context context) {

        super(context);

        initPaint();    //设置画笔

    }

    //设置数据

    public void setData(ArrayList<ViewData> viewDatas) {

        this.viewDatas = viewDatas;

        initData();     //设置数据的百分度和角度

        invalidate();   //刷新UI

    }

    public MyView(Context context, AttributeSet attrs) {

        super(context, attrs);

        initPaint();

    }

    public MyView(Context context, AttributeSet attrs, int defStyleAttr) {

        super(context, attrs, defStyleAttr);

        initPaint();

    }

    //初始化画笔

    private void initPaint() {

        paint = new Paint();

        //设置画笔默认颜色

        paint.setColor(Color.WHITE);

        //设置画笔模式：填充

        paint.setStyle(Paint.Style.FILL);

        //

        paint.setTextSize(30);

        //初始化区域

        rectF = new RectF();

    }

    //确定View大小

    @Override

    protected void onSizeChanged(int w, int h, int oldw, int oldh) {

        super.onSizeChanged(w, h, oldw, oldh);

        this.w = w;     //获取宽高

        this.h = h;

    }

    @Override

    protected void onDraw(Canvas canvas) {

        super.onDraw(canvas);

        canvas.translate(w / 2, h / 2);             //将画布坐标原点移到中心位置

        float currentStartAngle = 0;                //起始角度

        float r = (float) (Math.min(w, h) / 2);     //饼状图半径(取宽高里最小的值)

        rectF.set(-r, -r, r, r);                    //设置将要用来画扇形的矩形的轮廓

        for (int i = 0; i < viewDatas.size(); i++) {

            ViewData viewData = viewDatas.get(i);

            paint.setColor(viewData.color);

            //绘制扇形(通过绘制圆弧)

            canvas.drawArc(rectF, currentStartAngle, viewData.angle, true, paint);

            //绘制扇形上文字

            float textAngle = currentStartAngle + viewData.angle / 2;    //计算文字位置角度

            paint.setColor(Color.BLACK);

            float x = (float) (r / 2 * Math.cos(textAngle * Math.PI / 180));    //计算文字位置坐标

            float y = (float) (r / 2 * Math.sin(textAngle * Math.PI / 180));

            paint.setColor(Color.BLACK);        //文字颜色

            canvas.drawText(viewData.name, x, y, paint);    //绘制文字

            currentStartAngle += viewData.angle;     //改变起始角度

        }

    }

    private void initData() {

        if (null == viewDatas || viewDatas.size() == 0) {

            return;

        }

        float sumValue = 0;                 //数值和

        for (int i = 0; i < viewDatas.size(); i++) {

            ViewData viewData = viewDatas.get(i);

            sumValue += viewData.value;

        }

        for (ViewData data : viewDatas) {

            float percentage = data.value / sumValue;    //计算百分比

            float angle = percentage * 360;           //对应的角度

            data.percentage = percentage;

            data.angle = angle;

        }

    }

}

package myapplication.com.myapp.bean;

/**

 * Created by Administrator on 2017/1/8.

 */

public class ViewData {

    public String name; //名字

    public int value;   //数值

    public int color;   //颜色

    public float percentage; //百分比

    public float angle; //角度

    public ViewData(int value, String name,int color) {

        this.value = value;

        this.name = name;

        this.color=color;

    }

}

    ArrayList<ViewData> viewdata=new ArrayList<>();

  　　　　viewdata.add(new ViewData(30,"30%",getResources().getColor(R.color.circle_a)));

        viewdata.add(new ViewData(20,"20%",getResources().getColor(R.color.circle_b)));

        viewdata.add(new ViewData(27,"27%",getResources().getColor(R.color.circle_c)));

        viewdata.add(new ViewData(10,"10%",getResources().getColor(R.color.circle_d)));

        viewdata.add(new ViewData(13,"13%",getResources().getColor(R.color.circle_e)));

        myView.setData(viewdata);