CircleLayout.java 文件源码

private void drawChild(Canvas canvas, View child, LayoutParams lp) {
    mSrcCanvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
    mDstCanvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);

    mSrcCanvas.save();

    int childLeft = child.getLeft();
    int childTop = child.getTop();
    int childRight = child.getRight();
    int childBottom = child.getBottom();

    mSrcCanvas.clipRect(childLeft, childTop, childRight, childBottom, Op.REPLACE);
    mSrcCanvas.translate(childLeft, childTop);

    child.draw(mSrcCanvas);

    mSrcCanvas.restore();

    mXferPaint.setXfermode(null);
    mXferPaint.setColor(Color.BLACK);

    float sweepAngle = (lp.endAngle - lp.startAngle) % 361;

    mDstCanvas.drawArc(mBounds, lp.startAngle, sweepAngle, true, mXferPaint);
    mXferPaint.setXfermode(mXfer);
    mDstCanvas.drawBitmap(mSrc, 0f, 0f, mXferPaint);

    canvas.drawBitmap(mDst, 0f, 0f, null);
}