Feature: use module in cmake

app/src/main/cpp/CMakeLists.txt

@@ -10,38 +10,46 @@ cmake_minimum_required(VERSION 3.4.1)
 # 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.
-             media-handle
-
-             # Sets the library as a shared library.
-             SHARED
-
-             # Provides a relative path to your source file(s).
-
+set(SRC_FFMPEG
         ffmpeg/cmdutils.c
         ffmpeg/ffmpeg.c
         ffmpeg/ffmpeg_filter.c
         ffmpeg/ffmpeg_opt.c
         ffmpeg_cmd.c
         ffmpeg/ffprobe.c
-        ffmpeg/ffmpeg_hw.c
-        video_player.cpp
-        video_filter.c
-        ffprobe_cmd.cpp
-        video_cutting.cpp
+        ffmpeg/ffmpeg_hw.c)
+
+set(SRC_VISUALIZER
         visualizer/fft.cpp
         visualizer/fixed_fft.cpp
         visualizer/frank_visualizer.cpp
         visualizer/frank_visualizer_jni.cpp
-        visualizer/window.cpp
+        visualizer/window.cpp)
+
+set(SRC_METADATA
         metadata/media_retriever.cpp
         metadata/media_retriever_jni.cpp
         metadata/metadata_util.c
-        metadata/ffmpeg_media_retriever.c
+        metadata/ffmpeg_media_retriever.c)
+
+add_library( # Sets the name of the library.
+             media-handle
+
+             # Sets the library as a shared library.
+             SHARED
+
+             # Provides a relative path to your source file(s).
+        ${SRC_FFMPEG}
+        ${SRC_VISUALIZER}
+        ${SRC_METADATA}
+        video_player.cpp
+        video_filter.c
+        ffprobe_cmd.cpp
+        video_cutting.cpp
         yuv/yuv_converter.cpp
+        pcm/pcm_process.cpp
         media_transcode.cpp
         ff_audio_resample.cpp
-        pcm/pcm_process.cpp
         common_media_jni.cpp
         ff_audio_player.cpp
         audio_player_jni.cpp