Android自定义带圆点的半圆形进度条

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
/**
* 自定义带圆点的进度条
*/
public class HalfProgressBar extends View{
private int maxProgress = 100;
//设置进度条背景宽度
private float progressStrokeWidth = 3;
//设置进度条进度宽度
private float marxArcStorkeWidth = 6;
//设置进度条圆点的宽度
private float circularDotWidth=15;
/**
* 画笔对象的引用
*/
private Paint paint;
public synchronized int getProgress() {
return progress;
}
/**
* Android提供了Invalidate方法实现界面刷新，但是Invalidate不能直接在线程中调用，因为他是违背了单线程模型：Android UI操作并不是线程安全的，并且这些操作必须在UI线程中调用。
* 而postInvalidate()在工作者线程中被调用 使用postInvalidate则比较简单，不需要handler，直接在线程中调用postInvalidate即可。 
* @param progress 传过来的进度
*/
public void setProgress(int progress) {
if (progress < 0) {
progress = 0;
}
if (progress   maxProgress) {
progress = maxProgress;
}
if (progress <= maxProgress) {
this.progress = progress;
postInvalidate();
}
}
/**
* 当前进度
*/
private int progress = 99;
private RectF oval;
private int roundProgressColor;
private int roundColor;
private int circularDotColor;
public HalfProgressBar(Context context) {
super(context);
}
public HalfProgressBar(Context context, AttributeSet attrs) {
super(context, attrs);
paint = new Paint();
oval = new RectF();
//这是自定义view 必须要写的
TypedArray mTypedArray = context.obtainStyledAttributes(attrs, R.styleable.HalfProgressBar);
roundProgressColor = mTypedArray.getColor(R.styleable.HalfProgressBar_roundProgressColor1, Color.YELLOW);
roundColor=mTypedArray.getColor(R.styleable.HalfProgressBar_roundColor1, Color.YELLOW);
circularDotColor=mTypedArray.getColor(R.styleable.HalfProgressBar_circularDotColor1, Color.YELLOW);
}
public HalfProgressBar(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
paint = new Paint();
oval = new RectF();
TypedArray mTypedArray = context.obtainStyledAttributes(attrs, R.styleable.HalfProgressBar);
roundProgressColor = mTypedArray.getColor(R.styleable.HalfProgressBar_roundProgressColor1, Color.YELLOW);
roundColor=mTypedArray.getColor(R.styleable.HalfProgressBar_roundColor1, Color.YELLOW);
}
@Override
protected void onDraw(Canvas canvas) {
// TODO 自动生成的方法存根
super.onDraw(canvas);
float width = getWidth();
float height = getHeight();
paint.setAntiAlias(false); // 设置画笔为抗锯齿
paint.setColor(roundColor); // 设置画笔颜色
paint.setStrokeWidth(progressStrokeWidth); // 线宽
paint.setStyle(Paint.Style.STROKE);
oval.left = marxArcStorkeWidth / 2; // 左上角x
oval.top = circularDotWidth; // 左上角y
oval.right = width - circularDotWidth / 2; // 左下角x
oval.bottom = width - circularDotWidth / 2; // 右下角y
float bangjing = ((width - circularDotWidth/2) / 2);//半径
//调整圆背景的大小
canvas.drawArc(oval, 180, 180, false, paint); // 绘制红丝圆圈，即进度条背景
//进度条颜色
paint.setColor(roundProgressColor);
paint.setStrokeWidth(marxArcStorkeWidth);
canvas.drawArc(oval, 180, 180 * ((float) progress / (float) maxProgress), false, paint); // 绘制进度圆弧，这里是蓝色
//画圆点
paint.setColor(circularDotColor);
paint.setAntiAlias(true); // 设置画笔为抗锯齿
paint.setStyle(Paint.Style.FILL);
paint.setStrokeWidth(circularDotWidth);
//当画笔样式为STROKE或FILL_OR_STROKE时，设置笔刷的图形样式，如圆形样式Cap.ROUND,或方形样式Cap.SQUARE
paint.setStrokeCap(Paint.Cap.ROUND);
float jindu = ((float) progress * 1.8f);
canvas.drawPoint(bangjing - ((float) (Math.sin((Math.PI / (double) 180) * (jindu <= 90 ? 90 - (jindu) : -jindu + 90))) * bangjing),
bangjing+circularDotWidth - ((float) (Math.cos((Math.PI / (double) 180) * (double) (jindu <= 90 ? 90 - jindu : -jindu + 90))) * bangjing), paint);
}
}

<?xml version="1.0" encoding="utf-8"? 
<resources 
<!--自定义半圆形加载进度条-- 
<declare-styleable name="HalfProgressBar" 
<attr name="roundColor1" format="color"/ 
<attr name="roundProgressColor1" format="color"/ 
<attr name="circularDotColor1" format="color"/ 
</declare-styleable 
</resources 

<com.jyc99.demo.HalfProgressBar
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/view"
android:layout_centerHorizontal="true"
android:layout_marginTop="42dp"
android_custom:roundColor1="#fc422b"
android_custom:roundProgressColor1="#fa432e"
android_custom:circularDotColor1="#246223"/