android: fix build

[Vinschni]

I assume that line testedPaths.push_back(assetPath); is a residual from tests. It breaks android build.

 /home/vin/git/hello_imgui/build_android/hello_imgui_demodocking_AndroidStudio/app/jni/hello_imgui_subrepo/src/hello_imgui/internal/hello_imgui_assets.cpp:179:9: error: use of undeclared identifier 'testedPaths'
          testedPaths.push_back(assetPath);
          ^
  1 error generated.
  ninja: build stopped: subcommand failed.

[pthom]

Hi,

Thanks for pointing this out. I pushed a commit that removes this line. As I do not own an Android device anymore, I'd be interested in knowing whether the build succeeds for you :-)

[Vinschni]

I managed to build through hello_imgui_demodocking_AndroidStudio and generate "app-release-unsigned.apk" and "app-debug.apk".

Installation of "app-release-unsigned.apk" fails (package invalid) Instllation of "app-debug.apk" succeeds but on start I get an error due to missing hidapi lib. Its not build or linked in the cmake or project at any time.

[pthom]

Could you try to link it manually. For example with something like

target_link_libraries(hello_imgui_demodocking PRIVATE hidapi)

[Vinschni]

I added hidapi as submodule in ./external and tried to make cmake build recognize it by building and linking it.

Then i tried two ways. [1] Way

find_package(hidapi)
target_link_libraries(${target_name} hidapi )

after this line

but it does not find the folder... I tried to help it with

add_library(hidapi ${PROJECT_SOURCE_DIR}/../external/hidapi) 

but it does not work.

[2] Way I added after this line

set(HIDAPI_WITH_LIBUSB FALSE) # surely will be used only on Linux
set(BUILD_SHARED_LIBS FALSE) # HIDAPI as static library on all platforms
add_subdirectory(external/hidapi)

which gives me

--   No package 'libusb-1.0' found
CMake Error at /usr/local/share/cmake-3.20/Modules/FindPkgConfig.cmake:556 (message):
  A required package was not found
Call Stack (most recent call first):
  /usr/local/share/cmake-3.20/Modules/FindPkgConfig.cmake:778 (_pkg_check_modules_internal)
  external/hidapi/libusb/CMakeLists.txt:15 (pkg_check_modules)

I tried more things but don't get it to find and build that lib before trying to link it...

[pthom]

May be you could try to run without hidapi by commenting this line https://github.com/pthom/hello_imgui/blob/a6c6ffe4637885be23993938cef35be77c65d77b/hello_imgui_cmake/android/apkCMake/templates/sdl/apkCMake_activityClassName.java.in#L19 in hello_imgui_cmake/android/apkCMake/templates/sdl/apkCMake_activityClassName.java.in

[edcarllos]

First of all, congratulations on the project. I'm trying to run the demo projects for execution in an Android environment and have some problems.

I solved the first problem; in this case, the C++ version must be 17 because of the functional library. So I added this manually to CMakeLists in the Android Studio project and managed to get around it ["set(CMAKE_CXX_STANDARD 17)"].

On the other hand, I had the following problem: "unable to find library -lX11". I solved it by removing the call to the library from the configuration files.

Lastly, I came across this error regarding HIDAPI. I used the solution you suggested, and the error message mentioned above disappeared; however, the application does not open.

I'm running the project on a machine with Ubuntu 22.04. I'm available to help test some solutions. Thanks!

[pthom]

I'm sorry, I do not have an android device; so that it is difficult for me to run tests.

Could you try to run the application in a debugger and see where it stops or fails?

[edcarllos]

Thanks for the quick response. I tried running with Debug and got some information, but I wonder if it helped. To make it easier, I will post the photo with the execution in Android Studio. I highlighted the line where the error occurs.

[pthom]

I pushed some commits concerning Android. The build should now work directly. However, the app launches but shows nothing...

The solution should be somewhere inside https://github.com/libsdl-org/SDL/blob/main/docs/README-android.md

[pthom]

Apps now work under Android. They do not use the icon provided in assets/app_settings at the moment

[pthom]

Everything should be ok under Android now:

See docs about android setting customization: https://github.com/pthom/hello_imgui_template/

[pthom]

@edcarllos : can you please test on your side

[edcarllos]

@edcarllos : can you please test on your side

Wow! Works like a charm! Thanks Pascal!

The only project that wasn't work was "hello_imgui_demo_test_engine_AndroidStudio" but I guess it is because I need to compile with the option "-DHELLOIMGUI_WITH_TEST_ENGINE=ON"

I had to do just two little modifications in build instructions to work perfectly. When executing the script "../tools/android/cmake_arm-android.sh" is necessary to add the above folder as parameter (../tools/android/cmake_arm-android.sh ../). Furthermore, the variable "HELLOIMGUI_CMAKE_PATH" was not set correctly, so I added the command "set(HELLOIMGUI_CMAKE_PATH /home/users/Projects/CLion/hello_imgui/hello_imgui_cmake)" in the file hello_imgui_add_app.cmake and worked.

Again, thanks for the quick response. Now I will try to analyze how to enable the virtual keyboard in an Android environment to allow text editing in applications.

[pthom]

Thanks!

The only project that wasn't work was "hello_imgui_demo_test_engine_AndroidStudio" but I guess it is because I need to compile with the option "-DHELLOIMGUI_WITH_TEST_ENGINE=ON"

I think so. It might not work out of the box on android, since ImGui Test Engine requires threading.

is necessary to add the above folder as parameter (../tools/android/cmake_arm-android.sh ../)

Corrected, thanks!

the variable "HELLOIMGUI_CMAKE_PATH" was not set correctly

I'm working on related aspects now.

enable the virtual keyboard in an Android environment

SDL_StartTextInput might help

If you get something working, and have time to post an example or a screenshot, please do it (I just opened a gallery).

[edcarllos]

SDL_StartTextInput might help

If you get something working, and have time to post an example or a screenshot, please do it (I just opened a gallery).

Thanks for the tip. If something works I will post it here. If you need to test any other functionality in an Android environment, I am also available.