Passing struct through androidJavaObject.Call results in Exception: JNI: Unknown signature for type

Hi all,

Wondering if anyone knows if it is possible to send a C# struct through the JNI as a parameter.

I have a setup that is like this:

Code (CSharp):

1. public struct FileStruct
2. {
3.     public string path;
4.     public long byteOffset;
5.     public long assetLength;
6. }
7. public class PluginClass{
8.     public override void DoSomethingNative(FileStruct[] files)
9.     {
10.         pluginClass.Call("doSomethingNative",  files);
11.     }
12. }
13.  

Then on the android side I have the same struct defined as:

Code (CSharp):

1.  
2. package com.my.packagename;
3.  
4. public class FileStruct {
5.     public String path;
6.     public long byteOffset;
7.     public long assetLength;
8. }
9.  
10.  
11. public class PluginClass{
12.     public void doSomethingNative(FileStruct[] assets) {
13.         for (FileStruct asset : assets) {
14.             Log.i(TAG, "doSomethingNative: path: "
15.                     + asset.path
16.                     + " byteOffset: "
17.                     + asset.byteOffset
18.                     + " assetLength: "
19.                     + asset.assetLength);
20.         }
21.     }
22. }
23.  
24.  

Currently this throws the error:

Exception: JNI: Unknown signature for type 'FileStruct' (obj = FileStruct) equal

at UnityEngine._AndroidJNIHelper.GetSignature (System.Object obj) [0x00356] in <3c22a197ab60454cb70124c69f2248be>:0 

...

Is there any way to get something like this to work?? Do I need to create the AndroidJavaObject manually in C#?

 

I ended up solving this by serializing the array to a JSON object and passing that through to my plugin. I suppose it's an OK solution.

 

I'm having a similar issue. Sending a json or string is not an option as the it slows down my communication (~10 ms)