简单的圆形下载进度条

1. 上截图
2. 
3. 代码片段

   package org.zhx.rounprogress;
   
   
   import android.content.Context;
   import android.content.res.TypedArray;
   import android.graphics.Canvas;
   import android.graphics.Color;
   import android.graphics.Paint;
   import android.graphics.Path;
   import android.graphics.PathMeasure;
   import android.graphics.RectF;
   import android.graphics.Typeface;
   import android.util.AttributeSet;
   import android.util.Log;
   import android.view.View;
   
   /*
    * -----------------------------------------------------------------
    * Copyright (C) 2018-2020, by vogtec, All rights reserved.
    * -----------------------------------------------------------------
    * File: RoundProgress.java
    * Author: zhouxue
    * Version: 1.0
    * Create: 2018/5/25 14:23
    * Changes (from 2018/5/25)
    * -----------------------------------------------------------------
    * 2018/5/25 : Create RoundProgress.java (zhouxue);
    * -----------------------------------------------------------------
    */
   public class RoundProgress extends View {
       private String TAG=RoundProgress.class.getSimpleName();
       /**
        * 画笔对象的引用
        */
       private Paint paint;
   
       /**
        * 圆环的颜色
        */
       private int roundColor;
   
       /**
        * 圆环进度的颜色
        */
       private int roundProgressColor;
   
       /**
        * 中间进度百分比的字符串的颜色
        */
       private int textColor;
   
       /**
        * 中间进度百分比的字符串的字体
        */
       private float textSize;
   
       /**
        * 圆环的宽度
        */
       private float roundWidth;
   
       /**
        * 最大进度
        */
       private int max;
   
       /**
        * 当前进度
        */
       private int progress;
       /**
        * 是否显示中间的进度
        */
       private boolean textIsDisplayable;
   
       /**
        * 进度的风格，实心或者空心
        */
       private int style;
   
       public static final int STROKE = 0;
       public static final int FILL = 1;
   
       public RoundProgress(Context context) {
           this(context, null);
       }
   
       public RoundProgress(Context context, AttributeSet attrs) {
           this(context, attrs, 0);
       }
   
       public RoundProgress(Context context, AttributeSet attrs, int defStyle) {
           super(context, attrs, defStyle);
   
           paint = new Paint();
   
   
           TypedArray mTypedArray = context.obtainStyledAttributes(attrs,
                   R.styleable.RoundProgressBar);
   
           //获取自定义属性和默认值 （可以在xml 文件里 进行配置）
           roundColor = mTypedArray.getColor(R.styleable.RoundProgressBar_roundColor, Color.RED);
           roundProgressColor = mTypedArray.getColor(R.styleable.RoundProgressBar_roundProgressColor, Color.GREEN);
           textColor = mTypedArray.getColor(R.styleable.RoundProgressBar_roundtextColor, Color.GREEN);
           textSize = mTypedArray.getDimension(R.styleable.RoundProgressBar_roundtextSize, 15);
           roundWidth = mTypedArray.getDimension(R.styleable.RoundProgressBar_roundWidth, 5);
           max = mTypedArray.getInteger(R.styleable.RoundProgressBar_max, 100);
           textIsDisplayable = mTypedArray.getBoolean(R.styleable.RoundProgressBar_textIsDisplayable, true);
           style = mTypedArray.getInt(R.styleable.RoundProgressBar_style, 0);
   
           mTypedArray.recycle();
       }
   
       @Override
       protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
           super.onMeasure(widthMeasureSpec, heightMeasureSpec);
       }
   
       @Override
       protected void onDraw(Canvas canvas) {
           super.onDraw(canvas);
   
           /**
            * 画最外层的大圆环
            */
           int centre = getWidth()/2; //获取圆心的x坐标
           float dotWidth=4+roundWidth;// 圆弧上小圆点的半径
           int radius = (int) (centre - roundWidth/2-dotWidth); //圆环的半径
           paint.setColor(roundColor); //设置圆环的颜色
           paint.setStyle(Paint.Style.STROKE); //设置空心
           paint.setStrokeWidth(roundWidth); //设置圆环的宽度
           paint.setAntiAlias(true);  //消除锯齿
           canvas.drawCircle(centre, centre, radius, paint); //画出圆环
           /**
            * 画进度百分比
            */
           paint.setStrokeWidth(0);
           paint.setColor(textColor);
           paint.setTextSize(textSize);
           paint.setTypeface(Typeface.DEFAULT_BOLD); //设置字体
   
   
           int percent = (int)(((float)progress / (float)max) * 100);  //中间的进度百分比，先转换成float在进行除法运算，不然都为0
           float textWidth = paint.measureText(percent + "%");   //测量字体宽度，我们需要根据字体的宽度设置在圆环中间
   //        Log.e("log", centre + "@@"+percent+"!!!"+(textIsDisplayable +"!"+(percent != 0) +(style == STROKE)));
           if(textIsDisplayable && percent != 0 && style == STROKE){
               canvas.drawText(percent + "%", centre - textWidth / 2, centre + textSize/2, paint); //画出进度百分比
           }
   
   
           /**
            * 画圆弧 ，画圆环的进度
            */
   
           //设置进度是实心还是空心
           paint.setStrokeWidth(roundWidth); //设置圆环的宽度
           paint.setColor(roundProgressColor);  //设置进度的颜色
           RectF oval = new RectF(centre - radius, centre - radius, centre
                   + radius, centre + radius);  //用于定义的圆弧的形状和大小的界限
   
           switch (style) {
               case STROKE:{
                   paint.setStyle(Paint.Style.STROKE);
                   canvas.drawArc(oval, 0, 360 * progress / max, false, paint);  //根据进度画圆弧
                   break;
               }
               case FILL:{
                   paint.setStyle(Paint.Style.FILL_AND_STROKE);
                   if(progress !=0)
                       canvas.drawArc(oval, 0, 360 * progress / max, true, paint);  //根据进度画圆弧
                   break;
               }
           }
           // 圆弧上的小圆点
           if(progress max){
               progress = max;
           }
           if(progress <= max){
               this.progress = progress;
               Log.e(TAG, progress + "");
               postInvalidate();
           }
   
       }
   
   
       public int getCricleColor() {
           return roundColor;
       }
   
       public void setCricleColor(int cricleColor) {
           this.roundColor = cricleColor;
       }
   
       public int getCricleProgressColor() {
           return roundProgressColor;
       }
   
       public void setCricleProgressColor(int cricleProgressColor) {
           this.roundProgressColor = cricleProgressColor;
       }
   
       public int getTextColor() {
           return textColor;
       }
   
       public void setTextColor(int textColor) {
           this.textColor = textColor;
       }
   
       public float getTextSize() {
           return textSize;
       }
   
       public void setTextSize(float textSize) {
           this.textSize = textSize;
       }
   
       public float getRoundWidth() {
           return roundWidth;
       }
   
       public void setRoundWidth(float roundWidth) {
           this.roundWidth = roundWidth;
       }
   
   
   
   }
   

   4、下载demo 地址 https://github.com/zhoulinxue/RounProgress.git