Refactor project to migrate from experimental gradle to standard grad…

…le and Android Studio 2.2

Old stuff can be found on branch androidstudio_v1.4

README.md

@@ -1,17 +1,109 @@
-# Native OpenCV with Android Studio
+Native OpenCV with Android Studio
+=================================
 
-This application is a sample Android Studio project (tested on 1.4.1) with native OpenCV.
+This application is a sample Android Studio project (tested on version 2.2.2) with native OpenCV.
 
 It gets the camera frames, make JNI calls with its gray matrices references as parameters, add some random noise to the images from a C++ method, and render the generated frames.
 
-## Usage
+
+(Old stuff with experimental gradle and AndroidStudio 1.4 under the branch android_studio_v1.4).
+
+Usage
+-----
+
 Here is how to use this project to run native OpenCV code.
 
 * Make sure you have Android SDK up to date, with NDK installed
 * Download latest OpenCV SDK for Android from OpenCV.org and decompress the zip file.
 * Clone this project
-* Create a symlink named `jniLibs` in `app/src/main` that points to `$OPENCV_SDK/sdk/native/libs`
-* In `app/build.gradle` change line 25 to points to `$OPENCV_SDK/sdk/native`
+* Create a symlink named `jniLibs` in `app/src/main` that points to `YOUR_OPENCV_SDK/sdk/native/libs`
+* In `app/CMakeLists.txt` change line 9 to points to `YOUR_OPENCV_SDK/sdk/native/jni/include`
 * Sync gradle
 * Run the application
 
+
+How to create the native OpenCV project from scratch
+----------------------------------------------------
+
+Here is how I made this project. If you simply want to run openCV with NDK support, use the previous **Usage** chapter. If you want to build the full project from scratch, you can follow the steps in this chapter.
+
+* Make sure you have Android SDK up to date, with NDK installed
+* Download latest OpenCV SDK for Android from OpenCV.org and decompress the zip file.
+
+* Create a new Android Studio project
+  * Check Include C++ Support
+  * Choose empty Activity
+  * In C++ Support, you can check -fexceptions and -frtti
+
+* Import OpenCV library module
+  * New -> Import Module
+  * Choose the `/opt/opencv-android-sdk-v3.0/sdk/java` folder
+  * Unckeck replace jar, unckeck replace lib, unckeck create gradle-style
+
+* Set the OpenCV library module up to fit your SDK
+
+  Edit `openCVLibrary300/build.gradle` to fit your SDK:
+
+  ```
+    compileSdkVersion 25
+    buildToolsVersion "25.0.0"
+    defaultConfig {
+        minSdkVersion 19
+        targetSdkVersion 25
+    }
+  ```
+
+* Add OpenCV module dependency in your app module
+
+  File -> Project structure -> Module app -> Dependencies tab -> New module dependency -> choose OpenCV library module
+
+
+* Make a symlink named `jniLibs` in `app/src/main` that points to `YOUR_OPENCV_SDK/sdk/native/libs`
+
+* Set the app build.gradle
+  * Add abiFilters
+    ```
+        externalNativeBuild {
+            cmake {
+                cppFlags "-frtti -fexceptions"
+                abiFilters 'x86', 'x86_64', 'armeabi', 'armeabi-v7a', 'arm64-v8a', 'mips', 'mips64'
+            }
+        }
+    ```
+
+  * Add openCV jniLibs directory to point to the symlink
+    ```
+    sourceSets {
+        main {
+            jniLibs.srcDirs = ['src/main/jniLibs']
+        }
+    }
+    ```
+  See [build.gradle](app/build.gradle)
+
+* Configure the `CMakeLists.txt` file
+  * After the `cmake_minimum_required`, add
+    ```
+    include_directories(YOUR_OPENCV_SDK/sdk/native/jni/include)
+    add_library( lib_opencv SHARED IMPORTED )
+    set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/libopencv_java3.so)
+    ```
+  * At the end of the file add `lib_opencv` to the `target_link_libraries` list
+
+
+* Grant camera permission
+  * Add the following lines in the `AndroidManifest.xml` file
+    ```
+    <uses-permission android:name="android.permission.CAMERA"/>
+    <uses-feature android:name="android.hardware.camera"/>
+    <uses-feature android:name="android.hardware.camera.autofocus"/>
+    <uses-feature android:name="android.hardware.camera.front"/>
+    <uses-feature android:name="android.hardware.camera.front.autofocus"/>
+    ```
+
+
+* Add OpenCV code
+  * [MainActivity.java](app/src/main/java/ch/hepia/iti/opencvnativeandroidstudio/MainActivity.java)
+  * [activity_main.xml](app/src/main/res/layout/activity_main.xml)
+  * [native-lib.cpp](app/src/main/cpp/native-lib.cpp)
+

app/.gitignore

@@ -0,0 +1 @@
+/build

app/CMakeLists.txt

@@ -0,0 +1,56 @@
+
+# Sets the minimum version of CMake required to build the native
+# library. You should either keep the default value or only pass a
+# value of 3.4.0 or lower.
+
+cmake_minimum_required(VERSION 3.4.1)
+
+# OpenCV stuff
+include_directories(/opt/opencv-android-sdk-v3.0/sdk/native/jni/include)
+add_library( lib_opencv SHARED IMPORTED )
+set_target_properties(lib_opencv PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/src/main/jniLibs/${ANDROID_ABI}/libopencv_java3.so)
+
+# 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 it 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).
+             # Associated headers in the same location as their source
+             # file are automatically included.
+             src/main/cpp/native-lib.cpp )
+
+
+
+# Searches for a specified prebuilt library and stores the path as a
+# variable. Because system libraries are included 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 the
+# build script, prebuilt third-party libraries, or system libraries.
+
+target_link_libraries( # Specifies the target library.
+                       native-lib
+
+                       # OpenCV lib
+                       lib_opencv
+
+                       # Links the target library to the log library
+                       # included in the NDK.
+                       ${log-lib} )

app/build.gradle

@@ -0,0 +1,46 @@
+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 25
+    buildToolsVersion "25.0.0"
+    defaultConfig {
+        applicationId "ch.hepia.iti.opencvnativeandroidstudio"
+        minSdkVersion 19
+        targetSdkVersion 25
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        externalNativeBuild {
+            cmake {
+                cppFlags "-frtti -fexceptions"
+                abiFilters 'x86', 'x86_64', 'armeabi', 'armeabi-v7a', 'arm64-v8a', 'mips', 'mips64'
+            }
+        }
+    }
+    sourceSets {
+        main {
+            jniLibs.srcDirs = ['src/main/jniLibs']
+        }
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+    externalNativeBuild {
+        cmake {
+            path "CMakeLists.txt"
+        }
+    }
+}
+
+dependencies {
+    compile fileTree(include: ['*.jar'], dir: 'libs')
+    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+        exclude group: 'com.android.support', module: 'support-annotations'
+    })
+    compile 'com.android.support:appcompat-v7:25.0.1'
+    testCompile 'junit:junit:4.12'
+    compile project(':openCVLibrary300')
+}

app/proguard-rules.pro

@@ -0,0 +1,17 @@
+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in /home/adrien/Android/Sdk/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# Add any project specific keep options here:
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}