Add gradle support to android build script

.gitignore

@@ -56,10 +56,13 @@ android/android-ndk*
 android/android-sdk*
 android/assets
 android/bin
-android/obj
+android/build
 android/libs
+android/obj
+android/.gradle
 android-*
 *.apk
+*.keystore
 
 lib/curl
 lib/freetype

android/README.ANDROID

@@ -31,7 +31,8 @@ after some tweaks, but atm. only linux is supported.
 
 Dependencies list (may be incomplete):
 
-    autoconf, automake, make, python, ant, imagemagick, cmake, vorbis-tools
+    autoconf, automake, make, python, gradle, ant, imagemagick, cmake, 
+    vorbis-tools
 
 Additionally some dependencies for optimize_data script:
 
@@ -74,6 +75,13 @@ You can choose build type by setting BUILD_TYPE environment variable to "debug"
 or "release". The default is debug build. Note that if you choose release build,
 you have to manually sign the apk with your key and run zipalign.
 
+Additionally you can choose the build tool by setting BUILD_TOOL environment
+variable to "gradle" or "ant". Note that ant has been already removed from
+Android SDK, so you have to use SDK <= 25.2.5 for building with ant. By default 
+the BUILD_TOOL is set to "gradle". It has hardcoded version of SDK build-tools 
+that are set to "25.0.3", so you have to use this particular version (or you can
+edit build.gradle file).
+
 Basically if all dependencies are installed in the system, it should be enough
 to just run:
 

android/build.gradle

@@ -0,0 +1,31 @@
+buildscript
+{
+    repositories
+    {
+        jcenter()
+    }
+
+    dependencies
+    {
+        classpath 'com.android.tools.build:gradle:2.2.3'
+    }
+}
+
+apply plugin: 'com.android.application'
+
+android
+{
+    compileSdkVersion sdkVersion.toInteger()
+    buildToolsVersion "25.0.3"
+
+    sourceSets
+    {
+        main
+        {
+            manifest.srcFile 'AndroidManifest.xml'
+            jniLibs.srcDirs = ['libs']
+            res.srcDirs = ['res']
+            assets.srcDirs = ['assets']
+        }
+    }
+}

android/make.sh

@@ -22,16 +22,19 @@ export NDK_ABI_ARMV7=armeabi-v7a
 export ARCH_ARMV7=arm
 export HOST_ARMV7=arm-linux-androideabi
 export NDK_PLATFORM_ARMV7=android-19
+export SDK_VERSION_ARMV7=19
 
 export NDK_ABI_X86=x86
 export ARCH_X86=x86
 export HOST_X86=i686-linux-android
 export NDK_PLATFORM_X86=android-19
+export SDK_VERSION_X86=19
 
 export NDK_ABI_AARCH64=arm64-v8a
 export ARCH_AARCH64=arm64
 export HOST_AARCH64=aarch64-linux-android
 export NDK_PLATFORM_AARCH64=android-21
+export SDK_VERSION_AARCH64=21
 
 
 # A helper function that checks if error ocurred
@@ -75,16 +78,19 @@ if [ "$COMPILE_ARCH" = "armv7" ]; then
     export NDK_ABI=$NDK_ABI_ARMV7
     export ARCH=$ARCH_ARMV7
     export HOST=$HOST_ARMV7
+    export SDK_VERSION=$SDK_VERSION_ARMV7
 elif [ "$COMPILE_ARCH" = "x86" ]; then
     export NDK_PLATFORM=$NDK_PLATFORM_X86
     export NDK_ABI=$NDK_ABI_X86
     export ARCH=$ARCH_X86
     export HOST=$HOST_X86
+    export SDK_VERSION=$SDK_VERSION_X86
 elif [ "$COMPILE_ARCH" = "aarch64" ]; then
     export NDK_PLATFORM=$NDK_PLATFORM_AARCH64
     export NDK_ABI=$NDK_ABI_AARCH64
     export ARCH=$ARCH_AARCH64
     export HOST=$HOST_AARCH64
+    export SDK_VERSION=$SDK_VERSION_AARCH64
 else
     echo "Unknow COMPILE_ARCH: $COMPILE_ARCH. Possible values are: " \
          "armv7, aarch64, x86"
@@ -97,10 +103,12 @@ if [ -z "$BUILD_TYPE" ]; then
 fi
 
 if [ "$BUILD_TYPE" = "debug" ] || [ "$BUILD_TYPE" = "Debug" ]; then
-    export BUILD_TYPE="debug"
+    export ANT_BUILD_TYPE="debug"
+    export GRADLE_BUILD_TYPE="assembleDebug"
     export IS_DEBUG_BUILD=1
 elif [ "$BUILD_TYPE" = "release" ] || [ "$BUILD_TYPE" = "Release" ]; then
-    export BUILD_TYPE="release"
+    export ANT_BUILD_TYPE="release"
+    export GRADLE_BUILD_TYPE="assembleRelease"
     export IS_DEBUG_BUILD=0
 else
     echo "Unsupported BUILD_TYPE: $BUILD_TYPE. Possible values are: " \
@@ -108,6 +116,17 @@ else
     exit
 fi
 
+# Check selected build tool
+if [ -z "$BUILD_TOOL" ]; then
+    BUILD_TOOL="gradle"
+fi
+
+if [ "$BUILD_TOOL" != "gradle" ] && [ "$BUILD_TOOL" != "ant" ]; then
+    echo "Unsupported BUILD_TOOL: $BUILD_TOOL. Possible values are: " \
+         "gradle, ant"
+    exit
+fi
+
 # Check if we have access to the Android NDK and SDK
 if [ -z "$NDK_PATH" ]; then
     export NDK_PATH="$NDK_PATH_DEFAULT"
@@ -302,5 +321,12 @@ check_error
 
 # Build apk
 echo "Building APK"
-ant $BUILD_TYPE -Dsdk.dir="$SDK_PATH" -Dtarget=$NDK_PLATFORM
+
+if [ "$BUILD_TOOL" = "gradle" ]; then
+    export ANDROID_HOME="$SDK_PATH"
+    gradle -PsdkVersion=$SDK_VERSION $GRADLE_BUILD_TYPE
+elif [ "$BUILD_TOOL" = "ant" ]; then
+    ant $ANT_BUILD_TYPE -Dsdk.dir="$SDK_PATH" -Dtarget=$NDK_PLATFORM
+fi
+
 check_error