DrawingView.java 文件源码

/**
 * Set erase to true when the erase button is clicked.
 *
 * @param isErase {@code true} if erase is clicked {@code false} otherwise
 */
public void setErase(boolean isErase) {
    Xfermode xfermode = isErase ? new PorterDuffXfermode(
            PorterDuff.Mode.CLEAR) : null;
    drawPaint.setXfermode(xfermode);
}