code: private static PBXObjectRef createPBXContainerItemProxy(final PBXObjectRef containerPortal, final int proxyType,
        final String remoteInfo) {
      final Map map = new HashMap();
      map.put("isa", "PBXContainerItemProxy");
      map.put("containerPortal", containerPortal);
      map.put("proxyType", NumberFormat.getIntegerInstance(Locale.US).format(proxyType));
      map.put("remoteInfo", remoteInfo);
      return new PBXObjectRef(map);
    }
docs: Create a proxy for a file in a different project.
  
  @param containerPortal
  XcodeProject containing file.
  @param proxyType
  proxy type.
  @return PBXContainerItemProxy.