Android 圆弧形进度条 自定义View

前段时间一个项目需要做类似360扫描 圆弧形进度条

闲言碎语不要将-->

1.首先重写View 在XML layout中应用，我们需要在Value 文件夹下新建attrs.xml

在attrs.xml 里定义我们所需要的属性，然后就可以像Android自带的各种控件一

样在布局文件中一一引用。

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <declare-styleable name="CircleProgressBar">  
        <attr name="circleColor" format="color"/>
        <attr name="circleProgressColor" format="color"/>
        <attr name="circleWidth" format="dimension"></attr>
        <attr name="textColor" format="color" />  
        <attr name="textSize" format="dimension" /> 
        <attr name="max" format="integer"></attr> 
        <attr name="textIsDisplayable" format="boolean"></attr>
        <attr name="style">
            <enum name="STROKE" value="0"></enum>
            <enum name="FILL" value="1"></enum>
        </attr>
    </declare-styleable> 

</resources>

2.接着新建一个类CircleProgressBar extends View

我们需要在CircleProgressBar 的构造方法中获取 自己定义的属性。

TypedArray mTypedArray = context.obtainStyledAttributes(attrs,
R.styleable.CircleProgressBar);

先获取到TypedArray ,然后在通过TypedArray 获取到定义的各个属性。

circleColor = mTypedArray.getColor(R.styleable.CircleProgressBar_circleColor, 0xff47d8af);

mTypedArray.getColor() ,方法里的第一个参数是我们在attrs.xml 中定义的值，第二个参数是默认获取不到时的默认值（即我们没在布局文件中设置CircleProgressBar 的Color属性）

TypedArray mTypedArray = context.obtainStyledAttributes(attrs,
                R.styleable.CircleProgressBar);
        
        //获取自定义属性和默认值
        circleColor = mTypedArray.getColor(R.styleable.CircleProgressBar_circleColor, 0xff47d8af);
        circleProgressColor = mTypedArray.getColor(R.styleable.CircleProgressBar_circleProgressColor, Color.WHITE);
        textColor = mTypedArray.getColor(R.styleable.CircleProgressBar_textColor, Color.WHITE);
        textSize = mTypedArray.getDimension(R.styleable.CircleProgressBar_textSize, 40);
        roundWidth = mTypedArray.getDimension(R.styleable.CircleProgressBar_circleWidth, 3);
        max = mTypedArray.getInteger(R.styleable.CircleProgressBar_max, 100);
        textIsDisplayable = mTypedArray.getBoolean(R.styleable.CircleProgressBar_textIsDisplayable, true);
        style = mTypedArray.getInt(R.styleable.CircleProgressBar_style, 0);
        
        mTypedArray.recycle();

3.下面是CircleProgressBar 的全部代码

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PaintFlagsDrawFilter;
import android.graphics.RectF;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.view.View;

public class CircleProgressBar extends View {

    private Paint paint;
    private int circleColor;
    private int circleProgressColor;
    private int textColor;
    private float textSize;
    private float roundWidth;
    private int max;
    private int progress;
    private boolean textIsDisplayable;
    private int style;
    public static final int STROKE = 0;
    public static final int FILL = 1;
    
    public CircleProgressBar(Context context) {
        this(context, null);
    }

    public CircleProgressBar(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }
    
    public CircleProgressBar(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        
        paint = new Paint();
        TypedArray mTypedArray = context.obtainStyledAttributes(attrs,
                R.styleable.CircleProgressBar);
        
        //获取自定义属性和默认值
        circleColor = mTypedArray.getColor(R.styleable.CircleProgressBar_circleColor, 0xff47d8af);
        circleProgressColor = mTypedArray.getColor(R.styleable.CircleProgressBar_circleProgressColor, Color.WHITE);
        textColor = mTypedArray.getColor(R.styleable.CircleProgressBar_textColor, Color.WHITE);
        textSize = mTypedArray.getDimension(R.styleable.CircleProgressBar_textSize, 40);
        roundWidth = mTypedArray.getDimension(R.styleable.CircleProgressBar_circleWidth, 3);
        max = mTypedArray.getInteger(R.styleable.CircleProgressBar_max, 100);
        textIsDisplayable = mTypedArray.getBoolean(R.styleable.CircleProgressBar_textIsDisplayable, true);
        style = mTypedArray.getInt(R.styleable.CircleProgressBar_style, 0);
        
        mTypedArray.recycle();
    }
    

    @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
        int radius = (int) (centre - roundWidth/2); //圆环的半径
        paint.setColor(circleColor); //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.setDrawFilter(new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG|Paint.FILTER_BITMAP_FLAG)); 
        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
        
        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
        radius = (int) (centre - roundWidth*2);
        paint.setStrokeWidth(roundWidth*2); //设置圆环的宽度
        paint.setColor(circleProgressColor);  //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;
        }
        }
        
    }
    
    
    public synchronized int getMax() {
        return max;
    }

    /**
     * 设置进度的最大值
     * @param max
     */
    public synchronized void setMax(int max) {
        if(max < 0){
            throw new IllegalArgumentException("max not less than 0");
        }
        this.max = max;
    }

    /**
     * 获取进度.需要同步
     * @return
     */
    public synchronized int getProgress() {
        return progress;
    }

    /**
     * 设置进度，此为线程安全控件，由于考虑多线的问题，需要同步
     * 刷新界面调用postInvalidate()能在非UI线程刷新
     * @param progress
     */
    public synchronized void setProgress(int progress) {
        if(progress < 0){
            throw new IllegalArgumentException("progress not less than 0");
        }
        if(progress > max){
            progress = max;
        }
        if(progress <= max){
            this.progress = progress;
            postInvalidate();
        }
        
    }
    
    
    public int getCricleColor() {
        return circleColor;
    }

    public void setCricleColor(int cricleColor) {
        this.circleColor = cricleColor;
    }

    public int getCricleProgressColor() {
        return circleProgressColor;
    }

    public void setCricleProgressColor(int cricleProgressColor) {
        this.circleProgressColor = 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.最后说一下在布局文件中的使用

需要在.xml 布局文件的最外面一层加上

xmlns:android_custom="http://schemas.android.com/apk/res/com.example.circleprogress"这个即命名空间

注意：上面绿色字体部分随意写，橙色字体是工程的包名，别写错哦！

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:android_custom="http://schemas.android.com/apk/res/com.example.circleprogress"
    xmlns:tools="http://schemas.android.com/tools"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent" >  
  
  
    <com.example.circleprogress.CircleProgressBar  
        android:id="@+id/circleProgresBar"  
        android:layout_width="80dip"  
        android:layout_height="80dip"

        android_custom:circleColor="#47d8af"  
        android_custom:circleProgressColor="@android:color/white"  
        android_custom:textColor="@android:color/white"  
        android_custom:textIsDisplayable="true"  
        android_custom:roundWidth="2dp"  
        android_custom:textSize="40sp"/>  
</RelativeLayout> 

5.付效果图一张