How to load a binary file from the resources

[Kostas]

Hello all!

I have managed to compile the androidlcltest project and run it in my Galaxy Note Smartphone without big problems.

Now i wanted to go a step further and compile my neural network based backgammon engine with lazarus.

So i need to load the file with the paramters of the neural network.

I have put the file in the raw directory and it seems to be added to the apk android file at the end.

How can i now load the file?

To open a file stream does not seem to work, because the parameters file is embedded in the apk file as a resource.

So how can i access these resource data?

Thanks in advance
Kostas

[felipemdc]

When the application is installed the APK is uncompressed and the files are stored in the file system. From what I remember resource files will go to a directory /data/data/<package name> maybe /res/ afterwards too. So for the example: /data/data/com.pascal.lcltest/

Using "adb shell" you can access the directory and see for yourself where things are.

Your program always has read/write access to your own directory and you can use TFileStream or anything else to access files there. Later I will check this better, but I thought I'd give a partial answer anyway now as it will probably get you going.

[Kostas]

Thanks a lot.
I will try to give it a try as you describe it.

I have i have something new i will let you know.

Regards
Kostas

[meanderix]

I have put the file in the raw directory and it seems to be added to the apk android file at the end.

How can i now load the file?

To open a file stream does not seem to work, because the parameters file is embedded in the apk file as a resource.

So how can i access these resource data?

Ah, I didn't know about this approach. A different option would be to include the data in a resource script (.rc file.) That should work too.

Mattias

[meanderix]

I looked at this further and I don't think the raw files are extracted to /data/data/<packagename>. I think you need to use getResources().openRawResource(R.raw.yourfile) to access the resource file (from the Java side.) However, I would recommend using a resource script since then you can access it directly in pascal.

[Kostas]

Ah, I didn't know about this approach. A different option would be to include the data in a resource script (.rc file.) That should work too.

This does not seem to work when compiling for Android.

I created a .rc file and the data are included to the executable when i compile for Win32.

But when i compile for Android i get an error: androidlcltest.lpr(37,36) Error: Error while compiling resources. Compile with -vd for more details. Check for duplicates.

Any idea?

Kostas

[meanderix]

But when i compile for Android i get an error: androidlcltest.lpr(37,36) Error: Error while compiling resources. Compile with -vd for more details. Check for duplicates.

Any idea?

Hmm, I think I had a similar error -- I think I manually compiled it to a .res file and included that instead. It could be that you need to configure the resource compiler.

[Kostas]

Hmm, I think I had a similar error -- I think I manually compiled it to a .res file and included that instead. It could be that you need to configure the resource compiler.

Yes i converted first with brcc32 into a res file and included it in the exe.

But when i try to open it with: aResStream := TResourceStream.Create(HInstance, 'PORTESDATA', 'RT_RCDATA');
i get a runtime error: Resource 'PORTESDATA' not found.

The rc file that i created has the following line: PORTESDATA RCDATA "LeonPortes.coe"
This happens in Win64. I haven't yet tested in Android...

Any idea?

EDIT: The resource file is added in the executable
EDIT2: I am compiling in Win64 and run the program in a Windows7 64bit. No idea if this can be a problem...

Thanks in advance
Kostas

[meanderix]

The rc file that i created has the following line: PORTESDATA RCDATA "LeonPortes.coe"

The following worked for me:

Code: Text  [Select][+][-]

1. SVGDATA STR tiger.svg
2.  

Code: Text  [Select][+][-]

1.   S := TResourceStream.Create(HINSTANCE, PChar('SVGDATA'), PChar('STR'));
2.   try
3.     Doc.LoadFromStream(S);
4.   finally
5.     S.Free;
6.   end;
7.  

I'm using the LResources unit.

[Kostas]

The only way that worked for me is the use of lazarus resources.

1. I used lazres.exe to create a .lrs file:

Code: [Select]


        lazres network.lrs LeonPortes.coe


2. I included in the intialization section the .lrs file:

Code: [Select]


       {$I network.lrs}


3. I opened later the file using a TLazarusResourceStream:

Code: [Select]


       aLazRes := TLazarusResourceStream.Create('LeonPortes', 'COE');


Now it works right, also in Android!

Kostas

[felipemdc]

I looked at this further and I don't think the raw files are extracted to /data/data/<packagename>. I think you need to use getResources().openRawResource(R.raw.yourfile) to access the resource file (from the Java side.)

It doesn't need to be from the Java side. You can make such a call (any call actually, now that I learned more about it) in JNI in Pascal.

[Daniello]

It doesn't need to be from the Java side. You can make such a call (any call actually, now that I learned more about it) in JNI in Pascal.

I'm also interested in loading files, could you post a sample that uses the JNI?