PieChart 扇形中间位置限制文字计算

Question

  private void drawPieChart(Canvas canvas) {

    int centerX = getWidth() / 2;
    int centerY = getHeight() / 2;
    mPaint.setColor(mWrongColor);
    mRectF.set(centerX - mRadius, centerY - mRadius, centerX + mRadius, centerY + mRadius);
    float wrongPercent = mWrongPercent / 100f;
    canvas.drawArc(mRectF, mStartAngle, wrongPercent * 360 * mAnimaProgress, true, mPaint);


    if (!mAnimatorEnd) return;

    float textAngle = wrongPercent * (float) Math.PI + mStartRad;

    mPaint.setColor(Color.WHITE);
    mPaint.setTextAlign(Paint.Align.CENTER);
    mPaint.setTextSize(mTextSize);
    mPaint.setFakeBoldText(true);
    float startX, startY;
    if (mWrongPercent > 0) {
      startX = (float) (centerX + mRadius / 2 * Math.cos(textAngle));
      startY = (float) (centerY + mRadius / 2 * Math.sin(textAngle)) + mTextSize / 2;

      canvas.drawText(mWrongPercent + "", startX, startY, mPaint);
    }

    textAngle = (float) Math.PI * (1 + wrongPercent) + mStartRad;
    startX = (float) (centerX + mRadius / 2 * Math.cos(textAngle));
    startY = (float) (centerY + mRadius / 2 * Math.sin(textAngle)) + mTextSize / 2;

    canvas.drawText((100 - mWrongPercent) + "", startX, startY, mPaint);
  }