自定义圆形进度条效果图如下：应用场景如动态显示分数等。
view的自定义属性如下attr.xml
<?xml version="1.0" encoding="UTF-8"?>
<resources>
<declare-styleable name="ArcProgressbar">
<!-- 圆环起始角度-->
<attr name="startAngle" format="integer" />
<attr name="radius" format="integer" />
<!-- 圆环的宽度 默认115-->
<attr name="trokeWidth" format="integer" />
<!-- 进度条进度颜色 -->
<attr name="arcColor" format="color" />
</declare-styleable>
</resources>
view代码如下：
package com.gdmob.ui;
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Cap;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.TypedValue;
import android.view.View;
import com.cwits.cex.picc.R;
/**
* 自定义圆形进度条
* @author hai
*
*/
public class ArcProgressbar extends View {
/**
* 圆环半径
*/
private int mRadius = 115; // Diameter英文为直径，该常量表示小圆直径的dp值
/**
* 圆环的宽度
*/
private int mTrokeWidth = 15;
/**
* 起始角度
*/
private int mStartAngle = 135;
/**
* 进度条进度颜色
*/
private int mArcColor;
private Paint mPaint;
private int mProgress;// 表示进度
private RectF mRect;
private int mDiameter; // Diameter英文为直径，在该View中要绘制圆环，圆环由两个圆形确定（大圆和小圆），这个整形值表示小圆直径。
private int mWidth;// 这个值表示圆环的宽度的2倍（大圆直径-小圆直径）
private final int defaultColor; // 进度条背景颜色
public ArcProgressbar(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
defaultColor = Color.TRANSPARENT;
TypedArray ta = context.getTheme().obtainStyledAttributes(attrs, R.styleable.ArcProgressbar, defStyle, 0);
int num = ta.getIndexCount();
for (int i = 0; i < num; i++) {
int attr = ta.getIndex(i);
switch (attr) {
case R.styleable.ArcProgressbar_startAngle:
mStartAngle = ta.getInt(attr, 135);
break;
case R.styleable.ArcProgressbar_arcColor:
mArcColor = ta.getColor(attr, Color.parseColor("#eed306"));
break;
case R.styleable.ArcProgressbar_trokeWidth:
mTrokeWidth = ta.getInt(attr, 15);
break;
case R.styleable.ArcProgressbar_radius:
mRadius = ta.getInt(attr, 115);
break;
}
}
init();
}
public ArcProgressbar(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public ArcProgressbar(Context context) {
this(context, null);
}
private void init() {
Resources res = getResources();
// getDisplayMetrics()返回当前展示的metrics.
DisplayMetrics metrics = res.getDisplayMetrics();
// TypedValue.applyDimension(int unit, float value, DisplayMetrics
// metrics)
// 该方法中unit表示要转换成的单位，value表示数值，metrics表示当前的度量方式
// DIAMETER是常量0x1E,十进制为30，下面语句就表示tmp的值为30dp换算成的像素数值
float tmp = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, mRadius, metrics);
// ceil函数表示向上取整
mDiameter = (int) Math.ceil(tmp);
tmp = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, mTrokeWidth, metrics);
mWidth = (int) Math.ceil(tmp);
Paint p = new Paint();
p.setStyle(Paint.Style.STROKE);
p.setAntiAlias(true);
// setStrokeWidth()设置画笔宽度
// p.setStrokeWidth(0.5F*mWidth+0.5F*mDiameter);
p.setStrokeWidth(0.4F * mWidth);
p.setStrokeCap(Cap.ROUND);
p.setColor(defaultColor);
mPaint = p;
float rightTop = (float) (mWidth / 2.0);// 这个值就是圆环宽度（大圆半径-小圆半径）
mRect = new RectF(rightTop, rightTop, mDiameter + rightTop, mDiameter + rightTop);
mProgress = 0;
}
protected boolean clear = false;
@Override
protected void onDraw(Canvas canvas) {
// super.onDraw(canvas);
// 如果mProgress<360,则圆形进度条还未旋转完成，则用0x7f的透明度绘制一个完整的圆形作为进度条背景
// 注意要先绘制背景条，再绘制进度条，因为后绘制的会覆盖在先绘制的上面
/*
* if (mProgress < 360) { paint.setAlpha(0x7f);
* paint.setColor(defaultColor); canvas.drawArc(mRect, 135, 270, false,
* paint); }
*/
if (clear) {
mPaint.setColor(Color.TRANSPARENT);
clear = false;
return;
}
if (mProgress != 0) {
Paint paint = mPaint;
paint.setColor(mArcColor);
float degree = (float) (360.0f * mProgress / 360);
paint.setAlpha(0xff);
paint.setColor(mArcColor);
canvas.drawArc(mRect, mStartAngle, degree, false, paint);
}
}
@Override
protected final void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// mDiameter表示小圆直径，mWidth表示圆环宽度的2倍，所以meas表示大圆直径
// 所以View的hight，width都为meas
final int meas = mDiameter + mWidth;
setMeasuredDimension(meas, meas);
}
public void setProgress(int p) {
mProgress = p;
invalidate();
}
public void postProgress(final int p) {
post(new Runnable() {
@Override
public void run() {
setProgress(p);
}
});
}
public void setmArcColor(int mArcColor) {
this.mArcColor = mArcColor;
}
public void reset() {
clear = true;
invalidate();
mProgress = 0;
}
}
如上要让分数和进度条动态从0变到90，思路:定义一个变量mProgress=0,new一个定时任务，让mProgress慢慢从0 加到90后停止，
ArcProgressbar不停地调用setProgress(int p)就可以了。
代码如下：
private void setGrade(final int g) {
mProgress = 1;
arcProgressbar.reset();
final Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (0 < (mProgress / 3.6) && (mProgress / 3.6) <= 59) {
arcProgressbar.setmArcColor(Color.parseColor("#ff0000"));
tv_grade.setTextColor(Color.parseColor("#ff0000"));
} else if (60 < (mProgress / 3.6) && (mProgress / 3.6) <= 79) {
arcProgressbar.setmArcColor(Color.parseColor("#f39700"));
tv_grade.setTextColor(Color.parseColor("#f39700"));
} else if (80 < (mProgress / 3.6) && (mProgress / 3.6) <= 100) {
arcProgressbar.setmArcColor(Color.parseColor("#42ae7c"));
tv_grade.setTextColor(Color.parseColor("#42ae7c"));
}
if (msg.what == 0x1223) {
arcProgressbar.setProgress(mProgress * (1));
tv_grade.setText("" + (int) (mProgress / 3.6));
} else if (msg.what == 0x1224) {
tv_grade.setText("" + g);
}
}
};
new Timer().schedule(new TimerTask() {
@Override
public void run() {
Message msg = new Message();
if (mProgress < (int) (((float) 360 / 100) * g)) {
msg.what = 0x1223;
mProgress++;
} else {
msg.what = 0x1224;
this.cancel();
}
handler.sendMessage(msg);
}
}, 0, 5);
}