I'm trying to learn a bit of Android development.
I've started a new project for a simple hello world and it works fine.
The project is essentially the default one + one more header file in the cpp folder,
However I can't see such .cpp in the project mode, can anyone suggest how to fix this?
(See picture below).
I've attempted to change some setting in File > Project Structure but it doesn't seem to make any difference.
Maybe worth noticing that the header file isn't listed in the CMakeLists.txt at all.
# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html
# Sets the minimum version of CMake required to build the native library.
cmake_minimum_required(VERSION 3.4.1)
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} )
According to the android doc:
Known Issue: Android Studio currently shows you only the header files that have matching source files—even if you specify other headers in your CMake build script. See Issue #38068472
This means you need a pair filename.h and filename.cpp, you modify your CMakeLists.txt accordingly. The header file will be shown in project mode if it has a corresponding .cpp with the same name.
Reference:
https://developer.android.com/studio/projects/add-native-code
Related
Got error when I build the project like in the below. I tried so many things but never succeeded. I'm using m1 MacBook. Is this related with this error ?
[CXX1405] exception while building Json A problem occurred starting process 'command '/Users/serhat/Library/Android/sdk/cmake/3.18.1/bin/cmake''
in build.gradle:
externalNativeBuild {
cmake {
path "CMakeLists.txt"
}
}
and this is CmakeList.txt :
# For more information about using CMake with Android Studio,read the
# documentation: https://d.android.com/studio/projects/add-native-code.html
# Sets the minimum version of CMake required to build the native library.
cmake_minimum_required(VERSION 3.4.1)
# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} )
I fixed this issue :
softwareupdate --install-rosetta
I want to link expernal 'parquet' project ( https://github.com/apache/arrow/tree/master/cpp ) as part of my current project on Linux.
For this purposes I ran cmake of parquet with such parameters
cd build_parquet
cmake -DCMAKE_BUILD_TYPE=Release -DARROW_PARQUET=ON \
-DBoost_NO_BOOST_CMAKE=TRUE -DBoost_NO_SYSTEM_PATHS=TRUE -DBOOST_ROOT=${BOOST_BUILD_DIR}/include -DBOOST_LIBRARYDIR=${BOOST_BUILD_DIR}/lib/boost -DARROW_BOOST_USE_SHARED=OFF -DBOOST_INCLUDEDIR=${BOOST_BUILD_DIR}/include/boost ..
cmake --build . --config Release
// There are a lot of dependencies except boost, but only boost required to be installed on system, since other could be downloaded and installed by cmake script
Project successfully compiled. I got executable which could launch, generated static libs libarrow.a, libparquet.a, shared libraries libarrow.so, libparquet.so
In my main project I want to use such libraries and I use such commands in cmake to find them
find_path(PARQUET_INCLUDE_DIR NAMES arrow/api.h PATHS ${PARQUET_DIR}/src)
find_library(PARQUET_LIBRARY_RELEASE NAMES parquet.a
PATHS build_parquet/release/Release/ )
find_library(ARROW_LIBRARY_RELEASE NAMES arrow.a
PATHS build_parquet/release/Release/ )
set(PARQUET_LIBRARIES_RELEASE ${PARQUET_LIBRARY_RELEASE} ${ARROW_LIBRARY_RELEASE} )
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Parquet DEFAULT_MSG PARQUET_INCLUDE_DIR
${PARQUET_LIBRARIES_RELEASE } )
That's work okay, libraries and includes are found.
Then I link this libraries to my project
target_link_libraries(${myExe} ${PARQUET_LIBRARIES_RELEASE} ${mySomeOtherLibraries} )
after this I got enormous amount of linker errors such that
libparquet.a(column_writer.cc.o): In function `apache::thrift::transport::TMemoryBuffer::~TMemoryBuffer()':
column_writer.cc:(.text._ZN6apache6thrift9transport13TMemoryBufferD0Ev[_ZN6apache6thrift9transport13TMemoryBufferD5Ev]+0x3): undefined reference to `vtable for apache::thrift::transport::TMemoryBuffer'
.....
so that's what I don't understand much, why lib compiled well in parquet project itself but has a lot of unresolved now, when I use it to link in my own project? Moreover I compiled project for windows and when I did the same things, but with arrow.lib and parquet.lib (instead of libparquet.a and libarrow.a ) things worked fine! I was needed only to put arrow.dll, parquet.dll to executables to run project. But in Linux I've already crashed my head
So, why it doesn't work, what I should do to finally link the project with library ?
Update
I found the problem, I had to link libraries with adding .so files (not only .a files) like this
find_library(PARQUET_LIBRARY_RELEASE NAMES parquet.so parquet.a
PATHS build_parquet/release/Release/ )
find_library(ARROW_LIBRARY_RELEASE NAMES arrow.so arrow.a
PATHS build_parquet/release/Release/ )
set(PARQUET_LIBRARIES_RELEASE ${PARQUET_LIBRARY_RELEASE} ${ARROW_LIBRARY_RELEASE} )
Project is builded. So now the question is, why I need to add .so files to linker (in Windows only static .lib are enough), is it always a case when I build project in Linux ? Is order of linkage important ( .so files first and .a files next ? )
As Uwe wrote in a comment, the https://github.com/apache/parquet-cpp repository is deprecated, and the Parquet C++ library is being developed as part of the Apache Arrow C++ codebase https://github.com/apache/arrow/tree/master/cpp. Can you try building based on that, and if you have trouble can you post on the dev#arrow.apache.org mailing list?
You have succeed to build the project when link with the shared (.so) libraries instead of the static (.a) ones.
(The command find_library actually looks for one library, which name is listed in NAMES option. In your case it found .so library because its name comes before the .a one).
Actually, both shared and static parquet libraries contain the same set of symbols, and both sets are insufficient for link. The difference is that the shared library contains information, where to find remaining symbols (in the thrift library in your case), but the static library doesn't.
For correctly link with the static libraries, you need to list dependent libraries manually.
On Windows .lib file may mean either a static library, or a import file for the shared (.dll) one. It seems that you link with the dynamic one (it has no lib prefix), which succeed like on Linux.
I am trying to compile OpenCV in native on Android Studio. I am trying to follow : https://sriraghu.com/2017/03/11/opencv-in-android-an-introduction-part-1/
I was succesfully able to do it by following these steps on Windows. However on Ubuntu, its not working. The error is :
Execution failed for task ‘:app:externalNativeBuildDebug’.
Build command failed. Error while executing process /home/user/Android/Sdk/cmake/3.6.4111459/bin/cmake with arguments {–build
/home/user/AndroidStudioProjects/project_folders/app/.externalNativeBuild/cmake/debug/arm64-v8a
–target native-lib}
ninja: error: ‘../../../../jniLibs/src/main/jniLibs/arm64-v8a/libopencv_java3.so’,
needed by
‘../../../../build/intermediates/cmake/debug/obj/arm64-v8a/libnative-lib.so’,
missing and no known rule to make it
The CMakeLists.txt file is:
cmake_minimum_required(VERSION 3.4.1)
set(pathToOpenCV /media/user/Stuff/Softwares/OpenCV-android-sdk/sdk/native)
include_directories(${pathToOpenCV}/jni/include)
add_library( # Sets the name of the library.
native-lib
# Sets the library as a shared library.
SHARED
# Provides a relative path to your source file(s).
src/main/cpp/native-lib.cpp )
# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries in the search path by
# default, you only need to specify the name of the public NDK library
# you want to add. CMake verifies that the library exists before
# completing its build.
add_library(lib_opencv SHARED IMPORTED)
set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATIONS /home/user/cmu/android-apps/OpenCV_app_June23/OpenCV_Android/app/src/main/jniLibs/arm64-v8a/libopencv_java3.so)
find_library( # Sets the name of the path variable.
log-lib
# Specifies the name of the NDK library that
# you want CMake to locate.
log )
# Specifies libraries CMake should link to your target library. You
# can link multiple libraries, such as libraries you define in this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} lib_opencv)
In native-lib.cpp, I am able to add #include without any error prompts in Android Studio.
My previous searches suggest that there is something wrong with the paths. I have checked that the paths are correct, or is there a different way to put the path in Ubuntu?
I am trying to generate some Boost 1.58 libraries that I need (chrono, regex and thread) for Visual Studio 2012 and link the libraries with CMake. I have real problems for CMake and Visual Studio to find or link the libs, depending on the configuration I set.
I am finally using the following configuration:
bjam.exe --link=static --threading multi --variant=debug stage
But this doesn't seem to generate static libs.
How should I generate the libs and search them with CMake in order for Visual Studio to link them properly?
I finally came up with the solution and I think it is detailed enough to become a generic answer.
Visual Studio searches for dynamic libraries so we need to compile Boost libraries as shared, multithreaded, debug and release, and runtime-link shared. In windows using bjam.exe all commands have the prefix "--" except link, so the right way to build the libraries is:
bjam.exe link=shared --threading=multi --variant=debug --variant=release --with-chrono --with-regex --with-thread stage
This will generate the libs and DLLs in the folder Boost/stage/lib, so we need to set an environment variable Boost_LIBRARY_DIR C:/Boost/stage/lib, for example.
There are more options that may come in hand:
runtime-link = shared/static
toolset= msvc-11.0
The libraries will have a name like this for release:
boost_chrono-vc110-mt-1_58.lib
boost_chrono-vc110-mt-1_58.dll
And for debug:
boost_chrono-vc110-mt-gd-1_58.lib
boost_chrono-vc110-mt-gd-1_58.dll
In order for CMake to link them properly we need to write the following in the CMakeLists.txt:
add_definitions( -DBOOST_ALL_DYN_LINK ) //If not VS will give linking errors of redefinitions
set(Boost_USE_STATIC_LIBS OFF )
set(Boost_USE_MULTITHREADED ON)
set(Boost_USE_STATIC_RUNTIME OFF)
find_package(Boost COMPONENTS thread chrono regex REQUIRED )
INCLUDE_DIRECTORIES(${Boost_INCLUDE_DIRS})
TARGET_LINK_LIBRARIES( ${PROJ_NAME} ${Boost_LIBRARIES} )
bjam.exe --link=static --threading multi --variant=debug stage
But this doesn't seem to generate static libs.
Building the special stage target places Boost library binaries in the stage\lib\ subdirectory of the Boost tree.
More about building Boost on Windows here
CMake:
SET (CMAKE_BUILD_TYPE Debug) # in order to link with boost debug libs you may need to set that to build your program in debug mode (or do that from command line)
FIND_PACKAGE (Boost 1.58 COMPONENTS "chrono" "regex" "thread" REQUIRED)
#ADD_DEFINITIONS(-DBOOST_ALL_DYN_LINK) # make sure you don't have this as it will try to link with boost .dll's
INCLUDE_DIRECTORIES(${Boost_INCLUDE_DIRS})
LINK_DIRECTORIES(${Boost_LIBRARY_DIRS})
TARGET_LINK_LIBRARIES(${EXE_OR_LIB_NAME} ${Boost_LIBRARIES})
I guess this would be a generic question on including libraries with existing makefiles within cmake; but here's my context -
I'm trying to include scintilla in another CMake project, and I have the following problem:
On Linux, scintilla has a makefile in (say) the ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/gtk directory; if you run make in that directory (as usual), you get a ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/bin/scintilla.a file - which (I guess) is the static library.
Now, if I'd try to use cmake's ADD_LIBRARY, I'd have to manually specify the sources of scintilla within cmake - and I'd rather not mess with that, given I already have a makefile. So, I'd rather call the usual scintilla make - and then instruct CMAKE to somehow refer to the resulting scintilla.a. (I guess that this then would not ensure cross-platform compatibility - but note that currently cross-platform is not an issue for me; I'd just like to build scintilla as part of this project that already uses cmake, only within Linux)
So, I've tried a bit with this:
ADD_CUSTOM_COMMAND(
OUTPUT scintilla.a
COMMAND ${CMAKE_MAKE_PROGRAM}
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/gtk
COMMENT "Original scintilla makefile target" )
... but then, add_custom_command adds a "target with no output"; so I'm trying several approach to build upon that, all of which fail (errors given as comment):
ADD_CUSTOM_TARGET(scintilla STATIC DEPENDS scintilla.a) # Target "scintilla" of type UTILITY may not be linked into another target.
ADD_LIBRARY(scintilla STATIC DEPENDS scintilla.a) # Cannot find source file "DEPENDS".
ADD_LIBRARY(scintilla STATIC) # You have called ADD_LIBRARY for library scintilla without any source files.
ADD_DEPENDENCIES(scintilla scintilla.a)
I'm obviously quote a noob with cmake - so, is it possible at all to have cmake run a pre-existing makefile, and "capture" its output library file, such that other components of the cmake project can link against it?
Many thanks for any answers,
Cheers!
EDIT: possible duplicate: CMake: how do i depend on output from a custom target? - Stack Overflow - however, here the breakage seems to be due to the need to specifically have a library that the rest of the cmake project would recognize...
Another related: cmake - adding a custom command with the file name as a target - Stack Overflow; however, it specifically builds an executable from source files (which I wanted to avoid)..
You could also use imported targets and a custom target like this:
# set the output destination
set(SCINTILLA_LIBRARY ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/gtk/scintilla.a)
# create a custom target called build_scintilla that is part of ALL
# and will run each time you type make
add_custom_target(build_scintilla ALL
COMMAND ${CMAKE_MAKE_PROGRAM}
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/gtk
COMMENT "Original scintilla makefile target")
# now create an imported static target
add_library(scintilla STATIC IMPORTED)
# Import target "scintilla" for configuration ""
set_property(TARGET scintilla APPEND PROPERTY IMPORTED_CONFIGURATIONS NOCONFIG)
set_target_properties(scintilla PROPERTIES
IMPORTED_LOCATION_NOCONFIG "${SCINTILLA_LIBRARY}")
# now you can use scintilla as if it were a regular cmake built target in your project
add_dependencies(scintilla build_scintilla)
add_executable(foo foo.c)
target_link_libraries(foo scintilla)
# note, this will only work on linux/unix platforms, also it does building
# in the source tree which is also sort of bad style and keeps out of source
# builds from working.
OK, I think I have it somewhat; basically, in the CMakeLists.txt that build scintilla, I used this only:
ADD_CUSTOM_TARGET(
scintilla.a ALL
COMMAND ${CMAKE_MAKE_PROGRAM}
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/scintilla/gtk
COMMENT "Original scintilla makefile target" )
... and then, the slightly more complicated part, was to find the correct cmake file elsewhere in the project, where the ${PROJECT_NAME} was defined - so as to add a dependency:
ADD_DEPENDENCIES(${PROJECT_NAME} scintilla.a)
... and finally, the library needs to be linked.
Note that in the commands heretofore, the scintilla.a is merely a name/label/identifier/string (so it could be anything else, like scintilla--a or something); but for linking - the full path to the actual `scintilla.a file is needed (which in this project ends up in a variable ${SCINTILLA_LIBRARY}). In this project, the linking basically occurs through a form of a
list(APPEND PROJ_LIBRARIES ${SCINTILLA_LIBRARY} )
... and I don't really know how cmake handles the actual linking afterwards (but it seems to work)
For consistency, I tried to use ${SCINTILLA_LIBRARY} instead of scintilla.a as identifier in the ADD_CUSTOM_TARGET, but got error: "Target names may not contain a slash. Use ADD_CUSTOM_COMMAND to generate files". So probably this could be solved smarter/more correct with ADD_CUSTOM_COMMAND - however, I read that it "defines a new command that can be executed during the build process. The outputs named should be listed as source files in the target for which they are to be generated."... And by now I'm totally confused so as to what is a file, what is a label, and what is a target - so I think I'll leave at this (and not fix it if it ain't broken :) )
Well, it'd still be nice to know a more correct way to do this eventually,
Cheers!