转载请标明出处：http://blog.csdn.net/lmj623565791/article/details/43371299 ，本文出自：【张鸿洋的博客】

1、概述

最近需要用进度条，秉着不重复造轮子的原则，上github上搜索了一番，看了几个觉得比较好看的ProgressBar，比如：daimajia的等。简单看了下代码，基本都是继承自View，彻彻底底的自定义了一个进度条。盯着那绚丽滚动条，忽然觉得，为什么要通过View去写一个滚动条，系统已经提供了ProgressBar以及属于它的特性，我们没必要重新去构建一个，但是系统的又比较丑，不同版本变现还不一定一样。那么得出我们的目标：改变系统ProgressBar的样子。 

  对没错，我们没有必要去从0打造一个ProgressBar，人家虽然长的不好看，但是特性以及稳定性还是刚刚的，我们只需要为其整下容就ok了。 

说到整容，大家都知道我们的控件是通过onDraw()画出来的，那么我们只需要去覆盖它的onDraw()方法，自己写下就ok 。 

对了，我创建了一个微信公众号，欢迎关注，左边栏目上扫一扫即可。

  接下来，我们贴下效果图：

2、效果图

1、横向的进度条

2、圆形的进度条

没错，这就是我们的进度条效果，横向的模仿了daimajia的进度条样子。不过我们继承子ProgressBar，简单的为其整个容，代码清晰易懂 。为什么说，易懂呢？

横向那个进度条，大家会drawLine()和drawText()吧，那么通过getWidth()拿到控件的宽度，再通过getProgress()拿到进度，按比例控制绘制线的长短，字的位置还不是分分钟的事。

github源码地址：Android-ProgressBarWidthNumber欢迎大家star or fork 。

3、实现

横向的滚动条绘制肯定需要一些属性，比如已/未到达进度的颜色、宽度，文本的颜色、大小等。
本来呢，我是想通过系统ProgressBar的progressDrawable，从里面提取一些属性完成绘制需要的参数的。但是，最终呢，反而让代码变得复杂。所以最终还是改用自定义属性。 说道自定义属性，大家应该已经不陌生了。

1、HorizontalProgressBarWithNumber

1、自定义属性

values/attr_progress_bar.xml:

<?xml version="1.0" encoding="utf-8"?>  <resources>        <declare-styleable name="HorizontalProgressBarWithNumber">          <attr name="progress_unreached_color" format="color" />          <attr name="progress_reached_color" format="color" />          <attr name="progress_reached_bar_height" format="dimension" />          <attr name="progress_unreached_bar_height" format="dimension" />          <attr name="progress_text_size" format="dimension" />          <attr name="progress_text_color" format="color" />          <attr name="progress_text_offset" format="dimension" />          <attr name="progress_text_visibility" format="enum">              <enum name="visible" value="0" />              <enum name="invisible" value="1" />          </attr>      </declare-styleable>            <declare-styleable name="RoundProgressBarWidthNumber">          <attr name="radius" format="dimension" />      </declare-styleable>    </resources>

2、构造中获取

public class HorizontalProgressBarWithNumber extends ProgressBar  {     private static final int DEFAULT_TEXT_SIZE = 10;   private static final int DEFAULT_TEXT_COLOR = 0XFFFC00D1;   private static final int DEFAULT_COLOR_UNREACHED_COLOR = 0xFFd3d6da;   private static final int DEFAULT_HEIGHT_REACHED_PROGRESS_BAR = 2;   private static final int DEFAULT_HEIGHT_UNREACHED_PROGRESS_BAR = 2;   private static final int DEFAULT_SIZE_TEXT_OFFSET = 10;     /**    * painter of all drawing things    */   protected Paint mPaint = new Paint();   /**    * color of progress number    */   protected int mTextColor = DEFAULT_TEXT_COLOR;   /**    * size of text (sp)    */   protected int mTextSize = sp2px(DEFAULT_TEXT_SIZE);     /**    * offset of draw progress    */   protected int mTextOffset = dp2px(DEFAULT_SIZE_TEXT_OFFSET);     /**    * height of reached progress bar    */   protected int mReachedProgressBarHeight = dp2px(DEFAULT_HEIGHT_REACHED_PROGRESS_BAR);     /**    * color of reached bar    */   protected int mReachedBarColor = DEFAULT_TEXT_COLOR;   /**    * color of unreached bar    */   protected int mUnReachedBarColor = DEFAULT_COLOR_UNREACHED_COLOR;   /**    * height of unreached progress bar    */   protected int mUnReachedProgressBarHeight = dp2px(DEFAULT_HEIGHT_UNREACHED_PROGRESS_BAR);   /**    * view width except padding    */   protected int mRealWidth;      protected boolean mIfDrawText = true;     protected static final int VISIBLE = 0;     public HorizontalProgressBarWithNumber(Context context, AttributeSet attrs)   {    this(context, attrs, 0);   }     public HorizontalProgressBarWithNumber(Context context, AttributeSet attrs,     int defStyle)   {    super(context, attrs, defStyle);        setHorizontalScrollBarEnabled(true);      obtainStyledAttributes(attrs);      mPaint.setTextSize(mTextSize);    mPaint.setColor(mTextColor);     }      /**    * get the styled attributes    *     * @param attrs    */   private void obtainStyledAttributes(AttributeSet attrs)   {    // init values from custom attributes    final TypedArray attributes = getContext().obtainStyledAttributes(      attrs, R.styleable.HorizontalProgressBarWithNumber);      mTextColor = attributes      .getColor(        R.styleable.HorizontalProgressBarWithNumber_progress_text_color,        DEFAULT_TEXT_COLOR);    mTextSize = (int) attributes.getDimension(      R.styleable.HorizontalProgressBarWithNumber_progress_text_size,      mTextSize);      mReachedBarColor = attributes      .getColor(        R.styleable.HorizontalProgressBarWithNumber_progress_reached_color,        mTextColor);    mUnReachedBarColor = attributes      .getColor(        R.styleable.HorizontalProgressBarWithNumber_progress_unreached_color,        DEFAULT_COLOR_UNREACHED_COLOR);    mReachedProgressBarHeight = (int) attributes      .getDimension(        R.styleable.HorizontalProgressBarWithNumber_progress_reached_bar_height,        mReachedProgressBarHeight);    mUnReachedProgressBarHeight = (int) attributes      .getDimension(        R.styleable.HorizontalProgressBarWithNumber_progress_unreached_bar_height,        mUnReachedProgressBarHeight);    mTextOffset = (int) attributes      .getDimension(        R.styleable.HorizontalProgressBarWithNumber_progress_text_offset,        mTextOffset);      int textVisible = attributes      .getInt(R.styleable.HorizontalProgressBarWithNumber_progress_text_visibility,        VISIBLE);    if (textVisible != VISIBLE)    {     mIfDrawText = false;    }    attributes.recycle();   }

3、onMeasure

刚才不是出onDraw里面写写就行了么，为什么要改onMeasure呢，主要是因为我们所有的属性比如进度条宽度让用户自定义了，所以我们的测量也得稍微变下。

@Override   protected synchronized void onMeasure(int widthMeasureSpec,     int heightMeasureSpec)   {    int heightMode = MeasureSpec.getMode(heightMeasureSpec);      if (heightMode != MeasureSpec.EXACTLY)    {       float textHeight = (mPaint.descent() + mPaint.ascent());     int exceptHeight = (int) (getPaddingTop() + getPaddingBottom() + Math       .max(Math.max(mReachedProgressBarHeight,         mUnReachedProgressBarHeight), Math.abs(textHeight)));       heightMeasureSpec = MeasureSpec.makeMeasureSpec(exceptHeight,       MeasureSpec.EXACTLY);    }    super.onMeasure(widthMeasureSpec, heightMeasureSpec);     }

测量完，就到我们的onDraw了~~~

4、onDraw

@Override   protected synchronized void onDraw(Canvas canvas)   {    canvas.save();    //画笔平移到指定paddingLeft， getHeight() / 2位置，注意以后坐标都为以此为0，0    canvas.translate(getPaddingLeft(), getHeight() / 2);      boolean noNeedBg = false;    //当前进度和总值的比例    float radio = getProgress() * 1.0f / getMax();    //已到达的宽度    float progressPosX = (int) (mRealWidth * radio);    //绘制的文本    String text = getProgress() + "%";      //拿到字体的宽度和高度    float textWidth = mPaint.measureText(text);    float textHeight = (mPaint.descent() + mPaint.ascent()) / 2;      //如果到达最后，则未到达的进度条不需要绘制    if (progressPosX + textWidth > mRealWidth)    {     progressPosX = mRealWidth - textWidth;     noNeedBg = true;    }      // 绘制已到达的进度    float endX = progressPosX - mTextOffset / 2;    if (endX > 0)    {     mPaint.setColor(mReachedBarColor);     mPaint.setStrokeWidth(mReachedProgressBarHeight);     canvas.drawLine(0, 0, endX, 0, mPaint);    }       // 绘制文本    if (mIfDrawText)    {     mPaint.setColor(mTextColor);     canvas.drawText(text, progressPosX, -textHeight, mPaint);    }      // 绘制未到达的进度条    if (!noNeedBg)    {     float start = progressPosX + mTextOffset / 2 + textWidth;     mPaint.setColor(mUnReachedBarColor);     mPaint.setStrokeWidth(mUnReachedProgressBarHeight);     canvas.drawLine(start, 0, mRealWidth, 0, mPaint);    }      canvas.restore();     }     @Override   protected void onSizeChanged(int w, int h, int oldw, int oldh)   {    super.onSizeChanged(w, h, oldw, oldh);    mRealWidth = w - getPaddingRight() - getPaddingLeft();     }

其实核心方法就是onDraw了，但是呢，onDraw也很简单，绘制线、绘制文本、绘制线，结束。

还有两个简单的辅助方法：

/**    * dp 2 px    *     * @param dpVal    */   protected int dp2px(int dpVal)   {    return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,      dpVal, getResources().getDisplayMetrics());   }     /**    * sp 2 px    *     * @param spVal    * @return    */   protected int sp2px(int spVal)   {    return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,      spVal, getResources().getDisplayMetrics());     }

好了，到此我们的横向进度就结束了，是不是很简单~~如果你是自定义View，你还得考虑progress的更新，考虑状态的销毁与恢复等等复杂的东西。

接下来看我们的RoundProgressBarWidthNumber圆形的进度条。

2、RoundProgressBarWidthNumber 

圆形的进度条和横向的进度条基本变量都是一致的，于是我就让RoundProgressBarWidthNumber extends HorizontalProgressBarWithNumber 了。

然后需要改变的就是测量和onDraw了：

完整代码：

package com.zhy.view;    import android.content.Context;  import android.content.res.TypedArray;  import android.graphics.Canvas;  import android.graphics.Paint.Cap;  import android.graphics.Paint.Style;  import android.graphics.RectF;  import android.util.AttributeSet;    import com.zhy.library.view.R;    public class RoundProgressBarWidthNumber extends    HorizontalProgressBarWithNumber {   /**    * mRadius of view    */   private int mRadius = dp2px(30);     public RoundProgressBarWidthNumber(Context context) {    this(context, null);   }     public RoundProgressBarWidthNumber(Context context, AttributeSet attrs) {    super(context, attrs);      mReachedProgressBarHeight = (int) (mUnReachedProgressBarHeight * 2.5f);    TypedArray ta = context.obtainStyledAttributes(attrs,      R.styleable.RoundProgressBarWidthNumber);    mRadius = (int) ta.getDimension(      R.styleable.RoundProgressBarWidthNumber_radius, mRadius);    ta.recycle();      mTextSize = sp2px(14);      mPaint.setStyle(Style.STROKE);    mPaint.setAntiAlias(true);    mPaint.setDither(true);    mPaint.setStrokeCap(Cap.ROUND);     }     @Override   protected synchronized void onMeasure(int widthMeasureSpec,     int heightMeasureSpec) {    int heightMode = MeasureSpec.getMode(heightMeasureSpec);    int widthMode = MeasureSpec.getMode(widthMeasureSpec);      int paintWidth = Math.max(mReachedProgressBarHeight,      mUnReachedProgressBarHeight);      if (heightMode != MeasureSpec.EXACTLY) {       int exceptHeight = (int) (getPaddingTop() + getPaddingBottom()       + mRadius * 2 + paintWidth);     heightMeasureSpec = MeasureSpec.makeMeasureSpec(exceptHeight,       MeasureSpec.EXACTLY);    }    if (widthMode != MeasureSpec.EXACTLY) {     int exceptWidth = (int) (getPaddingLeft() + getPaddingRight()       + mRadius * 2 + paintWidth);     widthMeasureSpec = MeasureSpec.makeMeasureSpec(exceptWidth,       MeasureSpec.EXACTLY);    }      super.onMeasure(heightMeasureSpec, heightMeasureSpec);     }     @Override   protected synchronized void onDraw(Canvas canvas) {      String text = getProgress() + "%";    // mPaint.getTextBounds(text, 0, text.length(), mTextBound);    float textWidth = mPaint.measureText(text);    float textHeight = (mPaint.descent() + mPaint.ascent()) / 2;      canvas.save();    canvas.translate(getPaddingLeft(), getPaddingTop());    mPaint.setStyle(Style.STROKE);    // draw unreaded bar    mPaint.setColor(mUnReachedBarColor);    mPaint.setStrokeWidth(mUnReachedProgressBarHeight);    canvas.drawCircle(mRadius, mRadius, mRadius, mPaint);    // draw reached bar    mPaint.setColor(mReachedBarColor);    mPaint.setStrokeWidth(mReachedProgressBarHeight);    float sweepAngle = getProgress() * 1.0f / getMax() * 360;    canvas.drawArc(new RectF(0, 0, mRadius * 2, mRadius * 2), 0,      sweepAngle, false, mPaint);    // draw text    mPaint.setStyle(Style.FILL);    canvas.drawText(text, mRadius - textWidth / 2, mRadius - textHeight,      mPaint);      canvas.restore();     }    }

绘制的过程呢？

先绘制一个细一点的圆，然后绘制一个粗一点的弧度，二者叠在一起就行。文本呢，绘制在中间~~~总体，没什么代码量。

好了，两个进度条就到这了，是不是发现简单很多。总体设计上，存在些问题，如果抽取一个BaseProgressBar用于获取公共的属性；然后不同样子的进度条继承分别实现自己的测量和样子，这样结构可能会清晰些~~~

4、使用

布局文件

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:tools="http://schemas.android.com/tools"      xmlns:zhy="http://schemas.android.com/apk/res-auto"      android:layout_width="match_parent"      android:layout_height="match_parent" >        <LinearLayout          android:layout_width="match_parent"          android:layout_height="match_parent"          android:orientation="vertical"          android:padding="25dp" >            <com.zhy.view.HorizontalProgressBarWithNumber              android:id="@+id/id_progressbar01"              android:layout_width="match_parent"              android:layout_height="wrap_content"              android:layout_marginTop="50dip"              android:padding="5dp" />                       <com.zhy.view.HorizontalProgressBarWithNumber              android:layout_width="match_parent"              android:layout_height="wrap_content"              android:layout_marginTop="50dip"              android:padding="5dp"              android:progress="50"              zhy:progress_text_color="#ffF53B03"              zhy:progress_unreached_color="#ffF7C6B7" />            <com.zhy.view.RoundProgressBarWidthNumber              android:id="@+id/id_progress02"              android:layout_width="match_parent"              android:layout_height="wrap_content"              android:layout_marginTop="50dip"              android:padding="5dp"              android:progress="30" />            <com.zhy.view.RoundProgressBarWidthNumber              android:layout_width="match_parent"              android:layout_height="wrap_content"              android:layout_marginTop="50dip"              android:padding="5dp"              android:progress="50"              zhy:progress_reached_bar_height="20dp"              zhy:progress_text_color="#ffF53B03"              zhy:radius="60dp" />             </LinearLayout>    </ScrollView>

package com.zhy.sample.progressbar;    import android.app.Activity;  import android.os.Bundle;  import android.os.Handler;    import com.zhy.annotation.Log;  import com.zhy.view.HorizontalProgressBarWithNumber;    public class MainActivity extends Activity {     private HorizontalProgressBarWithNumber mProgressBar;   private static final int MSG_PROGRESS_UPDATE = 0x110;     private Handler mHandler = new Handler() {    @Log    public void handleMessage(android.os.Message msg) {     int progress = mProgressBar.getProgress();     mProgressBar.setProgress(++progress);     if (progress >= 100) {      mHandler.removeMessages(MSG_PROGRESS_UPDATE);           }     mHandler.sendEmptyMessageDelayed(MSG_PROGRESS_UPDATE, 100);    };   };     @Log   @Override   protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    mProgressBar = (HorizontalProgressBarWithNumber) findViewById(R.id.id_progressbar01);    mHandler.sendEmptyMessage(MSG_PROGRESS_UPDATE);     }    }

最后，本篇博客的目的呢？就是为了说下，类似ProgressBar这样的控件，如果你只是想去改变显示的样子，完全没必要从0去创建，复写onDraw即可，当然是个人观点，提出供大家参考。

源码点击下载  

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