/**

* 饼状图百分比控件

*/

public class PercentCircle extends View {

private final String tag = "PercentCircle";

/**

* 绘制百分比的圆，一共有两部分，分别是内圆、外圆；

* 思路：首先需要两支画笔, 设置画笔对应的属性等；

*/

/**

* 内部圆画笔

*/

private Paint mBackgroundInPaint;

/**

* 内部圆背景颜色

*/

private int mBackgroundInColor;

/**

* 圆心的坐标

*/

private int mCircleX;

private int mCircleY;

/**

* 当前角度

*/

private float mCurrentAngle;

/**

* 圆的外接矩形

*/

private RectF mArcRectF;

/**

* 开始绘制的角度

*/

private float mStartSweepValue;

/**

* 要绘制的角度

*/

private float mTargetPercent;

/**

* 外边圆的画笔

*/

private Paint mRingPaint;

/**

* 外层圆半径

*/

private int mRadius;

/**

* 外层圆颜色

*/

private int mRingColor;

private float newPercent;

public PercentCircle(Context context) {

super(context);

init(context);

}

public PercentCircle(Context context, AttributeSet attrs) {

super(context, attrs);

LogUtils.v(tag, "percentCircle:" + "PercentCircle(Context context, AttributeSet attrs)");

mRadius = 360;

// 背景圆的颜色

mBackgroundInColor = Color.WHITE;

// 外圆环的颜色

mRingColor = Color.parseColor("#a1e0fd");

init(context);

}

public PercentCircle(Context context, AttributeSet attrs, int defStyleAttr) {

super(context, attrs, defStyleAttr);

LogUtils.v(tag, "percentCircle:" + "PercentCircle(Context context, AttributeSet attrs, int defStyleAttr)");

init(context);

}

private void init(Context context) {

//圆环开始角度 -90° 正北方向

mStartSweepValue = -90;

//当前角度

mCurrentAngle = 0;

//设置中心园的画笔

mBackgroundInPaint = new Paint();

mBackgroundInPaint.setAntiAlias(true);

mBackgroundInPaint.setColor(mBackgroundInColor);

mBackgroundInPaint.setStyle(Paint.Style.FILL);

//设置外圆环的画笔

mRingPaint = new Paint();

mRingPaint.setAntiAlias(true);

mRingPaint.setColor(mRingColor);

mRingPaint.setStyle(Paint.Style.FILL);

}

// 主要是测量wrap_content时候的宽和高，因为宽高一样，只需要测量一次宽即可，高等于宽

@Override

protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

setMeasuredDimension(measure(widthMeasureSpec), measure(widthMeasureSpec));

}

// 当wrap_content的时候，view的大小根据半径大小改变，但最大不会超过屏幕

private int measure(int measureSpec) {

int result = 0;

//1、先获取测量模式 和 测量大小

//2、如果测量模式是MatchParent 或者精确值，则宽为测量的宽

//3、如果测量模式是WrapContent ，则宽为 直径值 与 测量宽中的较小值；否则当直径大于测量宽时，会绘制到屏幕之外；

int specMode = MeasureSpec.getMode(measureSpec);

int specSize = MeasureSpec.getSize(measureSpec);

if (specMode == MeasureSpec.EXACTLY) {

result = specSize;

} else {

result = (mRadius * 2);

if (specMode == MeasureSpec.AT_MOST) {

result = Math.min(result, specSize);

}

}

return result;

}

@Override

protected void onLayout(boolean changed, int left, int top, int right, int bottom) {

super.onLayout(changed, left, top, right, bottom);

//1、如果半径大于圆心的横坐标，需要手动缩小半径的值，否则画到屏幕之外；

//4、画背景圆的外接矩形，用来画圆环；

mCircleX = getMeasuredWidth() / 2;

mCircleY = getMeasuredHeight() / 2;

if (mRadius > mCircleX) {

mRadius = mCircleX;

}

mArcRectF = new RectF(mCircleX - mRadius, mCircleY - mRadius, mCircleX + mRadius, mCircleY + mRadius);

}

@Override

protected void onDraw(Canvas canvas) {

super.onDraw(canvas);

//1、先画外边大的圆

//1、再画中间的小圆覆盖大圆的中间部分

mRingColor = Color.parseColor("#a1e0fd");

mRingPaint.setColor(mRingColor);

canvas.drawArc(mArcRectF, mStartSweepValue, (float) (3.6 * mTargetPercent), true, mRingPaint);

mRingColor = Color.parseColor("#f99740");

mRingPaint.setColor(mRingColor);

canvas.drawArc(mArcRectF, (float) (mStartSweepValue + 3.6 * mTargetPercent), (float) (3.6 * newPercent), true, mRingPaint);

canvas.drawCircle(mCircleX, mCircleY, mRadius * 0.672f, mBackgroundInPaint);

}

public void setTargetPercent(float targetPercent) {

mTargetPercent = targetPercent;

}

public void setNewPercent(float newPercent) {

this.newPercent = newPercent;

}

}