以android通知為例：

獲取Notification.Builder，其中Builder為Notification的靜態內部類，鑑於Android 8.0通知的新特性，在new一個Builder的時候需要傳參ChannalId，所以需要適配低版本，

public static Notification.Builder getNotificationBuilder(Context context) {
    Notification.Builder builder = null;
    if (Build.VERSION.SDK_INT >= ToucConstants.VERSION_CODES_O) {
        builder = (Notification.Builder) getObjectFromInnerClass("android.app.Notification$Builder"
 
, context);
    } else {
        builder = new Notification.Builder(context);
    }
    return builder;
}

public static Object getObjectFromInnerClass(String clsName, Context context) {
    Object obj = null;
    try {
        Class c = Class.forName(clsName);
        if (c != null) {
            Constructor constructor = c.getDeclaredConstructor(new 
 
Class[]{Context.class, String.class});
            if (constructor != null) {
                obj = constructor.newInstance(context, id);
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return obj;
}