public void attr(String ns, String name, int resourceId, int type, Object obj) {
        if (nv != null) {
            nv.attr(ns, name, resourceId, type, obj);
        }
    }
add attribute to the node

@param ns
@param name
@param resourceId
@param type       {@link #TYPE_STRING} or others
@param obj        a string for {@link #TYPE_STRING} ,and Integer for others
android/third_party/apkbuilder/src/main/java/pxb/android/axml/NodeVisitor.java