android - 在具有浮雕效果的android中绘制圆边弧

Question

我正在尝试开发一个自定义组件，即弧形 slider ，我完成了弧形和拇指，但无法弄清楚如何绘制圆边弧以及其中的浮雕效果。目前 slider 看起来像这样

画圆弧的代码是

private void drawSlider(Canvas canvas) {
    float sweepDegrees = (value * arcWidthInAngle)
            / (maximumValue - minimumValue);

    // the grey empty part of the circle
    drawArc(canvas, startAngle, arcWidthInAngle, mTrackColor);
    // the colored "filled" part of the circle
    drawArc(canvas, startAngle, sweepDegrees, mFillColor);

    // the thumb to drag.       
    int radius = ((diameter/2) - (mArcThickness/2));
    Point thumbPoint = calculatePointOnArc(centerX, centerY, radius, startAngle + sweepDegrees);

    thumbPoint.x = thumbPoint.x - (mThumbDiameter/2);
    thumbPoint.y = thumbPoint.y - (mThumbDiameter/2);

    Bitmap thumbBitmap = BitmapFactory.decodeResource(
            mContext.getResources(), R.drawable.circle25);

    thumbBitmap = getResizedBitmap(thumbBitmap, mThumbDiameter, mThumbDiameter);
    canvas.drawBitmap(thumbBitmap, thumbPoint.x, thumbPoint.y,
            null);  

}

private void drawArc(Canvas canvas, float startAngle, float sweepDegrees,
        Paint paint) {
    if (sweepDegrees <= 0 || sweepDegrees > arcWidthInAngle) {
        return;
    }
    path.reset();
    path.arcTo(outerCircle, startAngle, sweepDegrees);
    path.arcTo(innerCircle, startAngle + sweepDegrees, -sweepDegrees);
    // innerCircle.
    path.close();
    canvas.drawPath(path, paint);
}

我的目标是这样的弧

Answer 1

对于圆形边缘，您可以使用 Paint.setStrokeCap() 方法。此外，默认的油漆帽是 BUTT。您应该改用 Paint.Cap.ROUND 帽。

例如:

Paint mFillColor = new Paint();
mFillColor.setStrokeCap(Paint.Cap.ROUND)