Use ebitenmobile to build for android throws errors (ebitenmobileview_android.c)

[scratch85]

Hi,

I wanted to build for android and adopted my project to look like the go-inovation example. Sadly I receive an error where I am not sure what could be the cause or how to debug further.

go version
go version go1.21.6 windows/amd64

From go.mod

module client

go 1.20

require github.com/hajimehoshi/ebiten/v2 v2.6.4

Error using ebitenmobile

PS> ebitenmobile bind -target android -javapkg com.warlords-client.game -o ./mobile/android/client/client.aar -androidapi=21 ./mobile
gomobile: go build -buildmode=c-shared -o=gomobile-work-680967744\android\src\main\jniLibs\x86_64\libgojni.so ./gobind failed: exit status 1
# gobind/gobind
ebitenmobileview_android.c:22:1: error: variable has incomplete type 'void'
ebitenmobileview_android.c:22:20: error: expected ';' after top level declarator

Any help is appreciated.

Thanks!

[hajimehoshi]

Which version of ebitenmobile are you using?

[hajimehoshi]

Could you try to run ebitenmobile command with -x so that you can see detailed logs?

[scratch85]

Could you try to run ebitenmobile command with -x so that you can see detailed logs?

Sure, here it is: ebitenmobile-output-20240124.txt
Already in line 27 it says:
gomobile: go build -x -buildmode=c-shared -o=C:\Users\me\AppData\Local\Temp\gomobile-work-3405399574\android\src\main\jniLibs\armeabi-v7a\libgojni.so ./gobind failed: exit status 1

It looks like there is an issue with gobind which actually produces this file named ebitenmobileview_android.c

[hajimehoshi]

Thanks! Would it be possible to see the content of ebitenmobileview_android.c? You can keep the files by specifying -work.

[scratch85]

Ahh, this is something that helps a lot:

From the gomobile docs:

The build flags -a, -i, -n, -x, -gcflags, -ldflags, -tags, -trimpath, and -work are shared with the build command. For documentation, see 'go help build'.

But hey, I found the issue today.
Using -javapkg com.client.game it works. Using -javapkg com.warlords-client.game fails with the error mentioned above.
Using -javapkg com.warlordsclient.game works as well, so the issue seems/is the "-" (minus/hyphen) in the -javapkg param or in general the way the cmd params (with go flag) work.

Many thanks for your help and your fast responses.

[hajimehoshi]

That's interesting. So using a hyphen didn't work well. I feel like this is a bug in gobind itself. I'd be nice if you could report this to github.com/golang/go.

[scratch85]

Just made a quick research about java package names. I think this is the root issue: Java does not support hyphens in package names.

• Hyphenated company name in Java packages
• Discussion on: Publishing a Python Package: What I Wish the Maze of Tutorials Covered

Actually this means it is not a real bug, just some input that isn't handled well :)

[hajimehoshi]

ebitenmobile could detect this issue earlier. Let me file an issue.