android: update 'debug' information support

cmake/android/OpenCVDetectAndroidSDK.cmake

@@ -9,7 +9,8 @@ if(DEFINED ANDROID_NDK_REVISION AND ANDROID_NDK_REVISION MATCHES "(1[56])([0-9]+
 endif()
 
 # fixup -g option: https://github.com/opencv/opencv/issues/8460#issuecomment-434249750
-if((INSTALL_CREATE_DISTRIB OR CMAKE_BUILD_TYPE STREQUAL "Release")
+if(INSTALL_CREATE_DISTRIB
+  AND (NOT BUILD_WITH_DEBUG_INFO AND NOT CMAKE_BUILD_TYPE MATCHES "Debug")
   AND NOT OPENCV_SKIP_ANDROID_G_OPTION_FIX
 )
   if(" ${CMAKE_CXX_FLAGS} " MATCHES " -g ")

cmake/android/android_ant_projects.cmake

@@ -201,8 +201,8 @@ macro(add_android_project target path)
             LIBRARY_OUTPUT_DIRECTORY "${android_proj_bin_dir}/libs/${ANDROID_NDK_ABI_NAME}"
             )
 
-        if (NOT (CMAKE_BUILD_TYPE MATCHES "debug"))
-            add_custom_command(TARGET ${JNI_LIB_NAME} POST_BUILD COMMAND ${CMAKE_STRIP} --strip-unneeded "$<TARGET_FILE:${JNI_LIB_NAME}>")
+        if(NOT BUILD_WITH_DEBUG_INFO AND NOT CMAKE_BUILD_TYPE MATCHES "Debug")
+          add_custom_command(TARGET ${JNI_LIB_NAME} POST_BUILD COMMAND ${CMAKE_STRIP} --strip-unneeded "$<TARGET_FILE:${JNI_LIB_NAME}>")
         endif()
       endif()
     endif()

modules/java/android_sdk/android_gradle_lib/build.gradle

@@ -11,11 +11,14 @@ android {
 
     buildTypes {
         debug {
-            packagingOptions{
-                doNotStrip '*.so'
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
             }
         }
         release {
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+            }
             minifyEnabled false
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
         }

modules/java/android_sdk/build.gradle.in

@@ -102,7 +102,15 @@ android {
     }
 
     buildTypes {
+        debug {
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+            }
+        }
         release {
+            packagingOptions {
+                doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+            }
             minifyEnabled false
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
         }

modules/java/jni/CMakeLists.txt

@@ -77,7 +77,7 @@ if(ANDROID)
 
   # force strip library after the build command
   # because samples and tests will make a copy of the library before install
-  if(NOT CMAKE_BUILD_TYPE MATCHES "Debug")
+  if(NOT BUILD_WITH_DEBUG_INFO AND NOT CMAKE_BUILD_TYPE MATCHES "Debug")
     add_custom_command(TARGET ${the_module} POST_BUILD COMMAND ${CMAKE_STRIP} --strip-unneeded "$<TARGET_FILE:${the_module}>")
   endif()
 endif()

platforms/android/build_sdk.py

@@ -143,6 +143,7 @@ class Builder:
         self.cmake_path = self.get_cmake()
         self.ninja_path = self.get_ninja()
         self.debug = True if config.debug else False
+        self.debug_info = True if config.debug_info else False
 
     def get_cmake(self):
         if not self.config.use_android_buildtools and check_executable(['cmake', '--version']):
@@ -217,6 +218,8 @@ class Builder:
 
         if self.debug:
             cmake_vars['CMAKE_BUILD_TYPE'] = "Debug"
+
+        if self.debug_info:  # Release with debug info
             cmake_vars['BUILD_WITH_DEBUG_INFO'] = "ON"
 
         if self.config.extra_modules_path is not None:
@@ -234,7 +237,7 @@ class Builder:
         # full parallelism for C++ compilation tasks
         execute([self.ninja_path, "opencv_modules"])
         # limit parallelism for Gradle steps (avoid huge memory consumption)
-        execute([self.ninja_path, '-j3', "install" if self.debug else "install/strip"])
+        execute([self.ninja_path, '-j3', "install" if (self.debug_info or self.debug) else "install/strip"])
 
     def build_javadoc(self):
         classpaths = []
@@ -291,7 +294,8 @@ if __name__ == "__main__":
     parser.add_argument('--no_ccache', action="store_true", help="Do not use ccache during library build")
     parser.add_argument('--force_copy', action="store_true", help="Do not use file move during library build (useful for debug)")
     parser.add_argument('--force_opencv_toolchain', action="store_true", help="Do not use toolchain from Android NDK")
-    parser.add_argument('--debug', action="store_true", help="Build for debug")
+    parser.add_argument('--debug', action="store_true", help="Build 'Debug' binaries (CMAKE_BUILD_TYPE=Debug)")
+    parser.add_argument('--debug_info', action="store_true", help="Build with debug information (useful for Release mode: BUILD_WITH_DEBUG_INFO=ON)")
     args = parser.parse_args()
 
     log.basicConfig(format='%(message)s', level=log.DEBUG)

samples/android/build.gradle.in

@@ -62,5 +62,32 @@ gradle.afterProject { project ->
                 }
             }
         }
+
+        // (you still need to re-build OpenCV with debug information to debug it)
+        if (true) {
+            gradle.println("Override doNotStrip-debug for the project ${project.name}")
+            project.android {
+                buildTypes {
+                    debug {
+                        packagingOptions {
+                            doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+                        }
+                    }
+                }
+            }
+        }
+        if (false || project.hasProperty("doNotStrip")) {
+            gradle.println("Override doNotStrip-release for the project ${project.name}")
+            project.android {
+                buildTypes {
+                    release {
+                        packagingOptions {
+                            doNotStrip '**/*.so'  // controlled by OpenCV CMake scripts
+                        }
+                    }
+                }
+            }
+        }
+
     }
 }