Add CMakeLists for Android build

Update CMakeLists.txt to download properly

Update README

Update CMakeLists

examples/example_sdl3_opengl3/CMakeLists.txt

@@ -0,0 +1,86 @@
+cmake_minimum_required(VERSION 3.6)
+
+project(ImGuiExample)
+
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+set(BUILD_FOR_ANDROID CACHE BOOL 0)
+
+set(DEAR_IMGUI_SRCS
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui_demo.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui_draw.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui_tables.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui_widgets.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../backends/imgui_impl_sdl3.cpp
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../backends/imgui_impl_opengl3.cpp
+)
+
+set(DEAR_IMGUI_HEADERS
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imconfig.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imgui_internal.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imstb_rectpack.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imstb_textedit.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../imstb_truetype.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../backends/imgui_impl_sdl3.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../backends/imgui_impl_opengl3.h
+)
+
+if(NOT DEFINED ENV{BUILD_FOR_ANDROID})
+  set(EXE "example_sdl3_opengl3")
+
+  include_directories(${CMAKE_CURRENT_SOURCE_DIR}/../.. ${CMAKE_CURRENT_SOURCE_DIR}/../../backends)
+
+  add_executable(${EXE} ${CMAKE_CURRENT_SOURCE_DIR}/main.cpp ${DEAR_IMGUI_SRCS})
+  find_package(SDL3 REQUIRED CONFIG REQUIRED COMPONENTS SDL3-shared)
+  find_package(OpenGL REQUIRED)
+  target_link_libraries(${EXE} PRIVATE GL GLU SDL3::SDL3)
+else()
+  message(STATUS "Building SDL3 app for Android...")
+
+  if(NOT DEFINED ENV{ANDROID_HOME})
+    message(FATAL_ERROR "Set ANDROID_HOME to path of Android Sdk.")
+  endif()
+
+  if(NOT DEFINED ENV{ANDROID_NDK_HOME})
+    message(FATAL_ERROR "Set ANDROID_NDK_HOME to path of Android Ndk.")
+  endif()
+
+  target_compile_definitions(${CMAKE_PROJECT_NAME} PRIVATE IMGUI_IMPL_OPENGL_ES3)
+
+  set(ANDROID_JNI_FILES
+    ${DEAR_IMGUI_SRCS}
+    ${DEAR_IMGUI_HEADERS}
+    ${CMAKE_CURRENT_SOURCE_DIR}/main.cpp)
+  set(JAVA_PKG_NAME "com.example.imgui")
+  set(SDL_DIR_NAME SDL-main)
+  set(ANDROID_BUILD_SCRIPT "${CMAKE_BINARY_DIR}/${SDL_DIR_NAME}/build-scripts/androidbuild.sh")
+
+  file(DOWNLOAD https://github.com/libsdl-org/SDL/archive/main.zip SHOW_PROGRESS ${CMAKE_BINARY_DIR}/${SDL_DIR_NAME}.zip STATUS DOWNLOAD_STATUS)
+  file(ARCHIVE_EXTRACT INPUT ${SDL_DIR_NAME}.zip)
+  # Separate the returned status code, and error message.
+  list(GET DOWNLOAD_STATUS 0 STATUS_CODE)
+  list(GET DOWNLOAD_STATUS 1 ERROR_MESSAGE)
+  # Check if download was successful.
+  if(${STATUS_CODE} EQUAL 0)
+    message(STATUS "Download completed successfully!")
+  else()
+    # Exit CMake if the download failed, printing the error message.
+    message(FATAL_ERROR "Error occurred during download: ${ERROR_MESSAGE}")
+  endif()
+
+  if(NOT EXISTS ${ANDROID_BUILD_SCRIPT})
+    message(FATAL_ERROR ": ${ANDROID_BUILD_SCRIPT} is not valid.")
+  endif()
+
+  set(ANDROID_APP_PREFIX ${CMAKE_BINARY_DIR}/${SDL_DIR_NAME}/build/${JAVA_PKG_NAME})
+  execute_process(COMMAND bash ${ANDROID_BUILD_SCRIPT} ${JAVA_PKG_NAME} ${ANDROID_JNI_FILES} WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
+  if(EXISTS ${ANDROID_APP_PREFIX}/app)
+    execute_process(COMMAND sed -i -e "s|-lGLESv2|-lGLESv3|" ${ANDROID_APP_PREFIX}/app/jni/src/Android.mk WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
+    execute_process(COMMAND sed -i -e "s|Game|${PROJECT_NAME}|g" ${ANDROID_APP_PREFIX}/app/src/main/res/values/strings.xml WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
+    execute_process(COMMAND sed -i -e "s|\"SDLActivity\"|\"${PROJECT_NAME}Activity\"|g" ${ANDROID_APP_PREFIX}/app/src/main/AndroidManifest.xml WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
+  endif()
+endif()

examples/example_sdl3_opengl3/README.md

@@ -1,40 +1,11 @@
+# Example SDL3 with OpenGL3
 
-# How to Build
+## Android
 
-## Windows with Visual Studio's IDE
+This example can run the Dear ImGui demo app on modern Android (targeting API 33+).
 
-Use the provided project file (.vcxproj). Add to solution (imgui_examples.sln) if necessary.
+Set JAVA_HOME, ANDROID_HOME, and ANDROID_NDK_HOME environment variables in order to run `CMakeLists.txt`.
 
-## Windows with Visual Studio's CLI
+Example CMake command to run from a "build" directory within this example: `BUILD_FOR_ANDROID=1 cmake ..`
 
-Use build_win32.bat or directly:
-```
-set SDL2_DIR=path_to_your_sdl3_folder
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x86 SDL3.lib opengl32.lib /subsystem:console
-#                 ^^ include paths     ^^ source files                                                                                    ^^ output exe                    ^^ output dir   ^^ libraries
-# or for 64-bit:
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x64 SDL3.lib SDL2mainopengl32.lib /subsystem:console
-```
-
-## Linux and similar Unixes
-
-Use our Makefile or directly:
-```
-c++ `sdl3-config --cflags` -I .. -I ../.. -I ../../backends
-  main.cpp ../../backends/imgui_impl_sdl3.cpp ../../backends/imgui_impl_opengl3.cpp ../../imgui*.cpp
-  `sdl3-config --libs` -lGL -ldl
-```
-
-## macOS
-
-Use our Makefile or directly:
-```
-brew install sdl3
-c++ `sdl3-config --cflags` -I .. -I ../.. -I ../../backends
-  main.cpp ../../backends/imgui_impl_sdl3.cpp ../../backends/imgui_impl_opengl3.cpp ../../imgui*.cpp
-  `sdl3-config --libs` -framework OpenGl -framework CoreFoundation
-```
-
-## Emscripten
-
-As of 2023-05-30 Emscripten doesn't support SDL3 yet.
+Example Gradle build: `ANDROID_HOME=MY_SDK_PATH ANDROID_NDK_HOME=MY_NDK_PATH build/SDL-main/build/my.java.pkg/gradlew installDebug`. This should install the demo app on a connected emulator or physical device.

examples/example_sdl3_opengl3/main.cpp

@@ -11,7 +11,14 @@
 #include "imgui_impl_sdl3.h"
 #include "imgui_impl_opengl3.h"
 #include <stdio.h>
+<<<<<<< HEAD
 #include <SDL3/SDL.h>
+=======
+
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_main.h>
+
+>>>>>>> e54b3b42 (Update CMakeLists.txt to download properly)
 #if defined(IMGUI_IMPL_OPENGL_ES2)
 #include <SDL3/SDL_opengles2.h>
 #else