This is the updated tutorial to set up and build an app with SDL2.0.10 in Android Studio 3.4.2 in Windows 10
This time I checked to make sure that the text formatting was correct efter I formattesd the quoted text. In the previous tutorial there were some missing characters. If you find some errors please point it out to make it easier for others. 
For this instructions we wish to create a app named DemolitionCrew. Change accordingly to your situation.
Since all the examples is from a real game I have just released on iOS, Android and Switch I will use its name.
We need to utilize not only the SDL2 main lib but also SDL2_Image, SDL2_net etc
I will compile and run this on a Samsung Galaxy S8+
1. Create this folder structure
Folder Structure
d:\Development\android
d:\Development\android\SDL2
d:\Development\android\SDL2_image
d:\Development\android\SDL2_mixer
d:\Development\android\SDL2_net
d:\Development\android\SDL2_ttf
2. Download these zip archives with source:
https://www.libsdl.org/download-2.0.php
https://www.libsdl.org/projects/SDL_image/
https://www.libsdl.org/projects/SDL_mixer/
https://www.libsdl.org/projects/SDL_net/
https://www.libsdl.org/projects/SDL_ttf
3. unpack every zip to individual folders
4. Copy the content to correct folders
From the SDL2.0.10 folder you copy the folder âandroid-projectâ to âd:\Development\androidâ
From the SDL2.0.10 folder you copy âincludeâ,âsrcâ and âAndroid.mkâ to d:\Development\android\SDL2
From the âSDL2_image-2.0.5â folder you copy all files ending with .c and .h and the folder âexternalâ and the file Android.mk to d:\Development\android\SDL2_image
From the âSDL2_ttf-2.0.15â folder you copy all files ending with .c and .h and the folder âexternalâ and the file Android.mk to d:\Development\android\SDL2_ttf
From the âSDL2_net-2.0.1â folder you copy all files ending with .c and .h and the file Android.mk to d:\Development\android\SDL2_net
From the âSDL2_mixer-2.0.4â folder you copy all files ending with .c and .h and the folders âexternalâ,ânative_midiâ,âtimidityâ and the file Androis.mk to d:\Development\android\SDL2_mixer
5a. Disable WebP in SDL_image
If you doesnât have to have support for WebP you can edit the âAndroid.mkâ file
so that line 16 says âSUPPORT_WEBP ?= falseâ
This time I just left it to true. It worked fine.
5b. Disable mp3 in SDL_Mixer
If you doesnât have to support mp3 and can stick to OGG instead do disable this.
I tried around a bit until I got tired of the mpg123 issue. So this was my solution. (Brutal)
I guess this can all be solved by finding a correct library, but since I donât use mp3 I just removed itsall together.
remove these lines in d:\Development\android\SDL2_mixer\Android.mk
SUPPORT_MP3_MPG123 ?= true
MPG123_LIBRARY_PATH := external/mpg123-1.25.6
and further down in the same file:
ifeq ($(SUPPORT_MP3_MPG123),true)
LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(MPG123_LIBRARY_PATH)
LOCAL_CFLAGS += -DMUSIC_MP3_MPG123
LOCAL_SHARED_LIBRARIES += mpg123
endif
In the SDL_Mixer folder i removed these files:
d:\Development\android\SDL2_mixer\music_mpg123.h
d:\Development\android\SDL2_mixer\music_mpg123.c
The entire folder d:\Development\android\SDL2_mixer\external\mpg123-1.25.6
In the file d:\Development\android\SDL2_mixer\music.c I commented out line 40
//#include âmusic_mpg123.hâ
If you discover this later on, a rebuild might not do it. In that case you just have to
remove the âdebugâ and âreleaseâ folder in
D:\Development\android\DemolitionCrew\app.externalNativeBuild\ndkBuild
This could ofcourse be handled better but I didnât have time for it.
6. Create the Project.
In the folder âd:\Development\androidâ
Rename the folder âandroid-projectâ to what you want your project to be called.
In this case we name it âDemolitionCrewâ
7. Start the command promt (WINKEY+R, Write âcmdâ Enter)
Create these links so they will appear as linked folders in the project. It is important that
you have named your project folder in beforehand. Otherwise they diappear.
mklink /J d:\Development\android\DemolitionCrew\app\jni\SDL d:\Development\android\SDL2
mklink /J d:\Development\android\DemolitionCrew\app\jni\SDL_image d:\Development\android\SDL2_image
mklink /J d:\Development\android\DemolitionCrew\app\jni\SDL_mixer d:\Development\android\SDL2_mixer
mklink /J d:\Development\android\DemolitionCrew\app\jni\SDL_net d:\Development\android\SDL2_net
mklink /J d:\Development\android\DemolitionCrew\app\jni\SDL_ttf d:\Development\android\SDL2_ttf
8. Download and start Start Android Studio 3.4.2
I choosed to install it in âd:\Android Studioâ
Start Android Studio
âDo not import settingsâ (I choosed this becuase I have a new installation)
âAndroid Studio Setup Wizardâ will start
Choose âStandardâ
Choose your prefered theme and then finish.
Android Studio will now download all the components.
Click on âOpen an existing Android Studio Projectâ
Navigate to âd:\Development\androidâ and select your project. In this case âDemolitionCrewâ.
Click âOpenâ
If this is the first time you run Android Studio it will need you to accept the Licence agreement.
In the right bottom window you will find a link that says âInstall missing SDK packagesâ
Clicking on that will bring up a window where you can accept the licens agreement.
Click âagreeâ and the next.
Android studio will install all the components.
After that is done click âFinishâ.
In the bottom right window it might say âError: NDK not configuredâ Click on the link âInstall NDKâ
When done it will try to compile and fail.
9. Change view
In the almost top left corner you can alter the view between âAndroidâ and âProjectâ
Change to âProjectâ if it is not already choosen.
Expand the tree view DemolitionCrew->app->src->main
Double Click on AndroidManifest.xml
Change the package=âorg.libsdl.appâ on line 6 to "package=âcom.xirbx.gamesâ (Or what your company and app name is)
The android:versionCode=â1â Not sure if this needs to be increased for each release on the google play store, but increase it anyways.
Change this to required true if you want touch screen to work on all smart phones.
<uses-feature
android:name="android.hardware.touchscreen"
android:required="true" />
Add these lines under the other permission lines if you wish SDL_net to access your local net and the internet
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
Save the file (CTRL+S)
10. Expand the tre view to this:
DemolitionCrew->app->jni
Double click on âApplication.mkâ
Uncomment line 5 so that it says âAPP_STL := c++_sharedâ
Make sure line 10 says: âAPP_PLATFORM=android-16â
Add a line underneath that says âAPP_CPPFLAGS += -fexceptionsâ
Expand the tree to DemolitionCrew->app
Double click on build.gradle
Make sure line 16 says :
minSdkVersion 16
Make sure line 22 says:
arguments âAPP_PLATFORM=android-16â
Change the ApplicationId on line 14 to this:
applicationId âcom.xirbx.games.demolitioncrewâ
NOTE! On line 18 you need to increase the versionCode for each build you
upload to Google Play
11. Expand the tre view to this:
DemolitionCrew->app->jni->src
Double click on âAndroid.mkâ
Change line 14 from
LOCAL_SHARED_LIBRARIES := SDL2
to:
LOCAL_SHARED_LIBRARIES := SDL2 \ SDL2_image \ SDL2_mixer \ SDL2_ttf \ SDL2_net
Change line 12 from:
LOCAL_SRC_FILES := YourSourceHere.c
to
LOCAL_SRC_FILES := \ AssetManager.cpp \ Components.cpp \ ECS.cpp \ Game.cpp \ GameClient.cpp \ GameMap.cpp \ main.cpp \ TextureManager.cpp \ tinyxml2.cpp \ UrlReader.cpp \ Vector2D.cpp \ xmltest.cpp \ ResourcePath.cpp \ tmxparser/base64/base64.cpp \ tmxparser/miniz.c \ tmxparser/TmxColor.cpp \ tmxparser/TmxEllipse.cpp \ tmxparser/TmxGroupLayer.cpp \ tmxparser/TmxImage.cpp \ tmxparser/TmxImageLayer.cpp \ tmxparser/TmxLayer.cpp \ tmxparser/TmxMap.cpp \ tmxparser/TmxObject.cpp \ tmxparser/TmxObjectGroup.cpp \ tmxparser/TmxPolygon.cpp \ tmxparser/TmxPolyline.cpp \ tmxparser/TmxProperty.cpp \ tmxparser/TmxPropertySet.cpp \ tmxparser/TmxTerrain.cpp \ tmxparser/TmxTerrainArray.cpp \ tmxparser/TmxText.cpp \ tmxparser/TmxTile.cpp \ tmxparser/TmxTileLayer.cpp \ tmxparser/TmxTileOffset.cpp \ tmxparser/TmxTileset.cpp \ tmxparser/TmxUtil.cpp
NOTE! You only have to list your .cpp and .c files. It will get the header-files
automatically.
Save the file (CTRL + S)
12. Expand DemolitionCrew->app->src->main
Here you will see âjavaâ, âresâ and âAndroidManifest.xmlâ
NOTE! It is easy to accidentally choose the wrong src-folder.
Right click on âDemolitionCrew->app->src->mainâ
Select New->Folder->Assets Folder. (NOT Directory. the folder option is the one with a android figure on)
A window pops up. Click âFinishâ
A new folder is created called âassetsâ
13. It is OK to breath now!
Now you can minimize the Android studio window and in windows
open up our project folder:
In this folder i place all my assets:
D:\Development\android\DemolitionCrew\app\src\main\assets
Assets are stuff like all your game graphics, sound, music and levels.
In this folder i place all my C++ and C code
D:\Development\android\DemolitionCrew\app\jni\src
Also place all the header files for SDL including SDL_mixer.h, SDL_image.h, SDL_ttf.h and SDL_net.h
I guess there is a better way to do this but I was desperate.
14. Go back to Android Studio
Navigate to DemolitionCrew->app->jni->src in the tree view
If you have a a main.cpp file, it can look something like this.
#include "main.h"
extern "C"
{
using namespace std;
Game *game=nullptr;
int SDL_main(int argc, char* argv[])
{
game = new Game();
game->gameState=gs_LOADING_GAME;
game->init("Game"); // Setting up SDL stuff and open screens
while(game->running())
{
game->update();
game->render();
}
game->clean();
return 0;
}
}
The important stuff here is the extern âCâ after the #includes but before everything else
and that you should use SDL_main() instead of plain main()
15. It is time to make a java-class for our game.
Navigate to DemolitionCrew->app->src->main->java
Right click âjavaâ and select âNew->Packageâ. Name it âcom.xirbx.gamesâ
Right click âcom.xirbx.gamesâ and select âNew->Fileâ. Name it âDemolitionCrew.javaâ (Or your game name)
Double click on DemolitionCrew.java
and paste this text:
package com.xirbx.games;
import org.libsdl.app.SDLActivity;
/**
* A sample wrapper class that just calls SDLActivity
*/
public class DemolitionCrew extends SDLActivity { }
16. Expand the tree view DemolitionCrew->app->src->main
Double Click on AndroidManifest.xml
On line 58 , change from:
<activity android:name="SDLActivity"
To:
<activity android:name="DemolitionCrew"
Save file (CTRL + S)
17. Naming the Game Icon
Expand the tree to this:
DemolitionCrew->app->src->main->res->values
Double click on the âstrings.xmlâ
Change:
<string name="app_name">Game</string>
To:
<string name="app_name">Demolition Crew</string>
This string is where the AndroidManifest.xml gets its game name value from.
I guess you can localize this for different languages.
18. Changing the Icon picture
Expand the tree to this:
DemolitionCrew->app->src->main->res
In each folder that begins with âmipmapâ there is a png image called âic_launcher.pngâ
Replace those with your own images.
Make sure they are the correct sizes.
I think it is easier to change those from windows and not in Android studio.
19. When all this is done you should be able to build the entire project. (CTRL +F9)
20. Connect a Android device (That is set to developer mode I guess) and press Run (SHIFT +F10)
I hope this tutorial saved you some time. Please check out my games on App store, Google Play
and Nintendo eShop!
Jesper / xirBX AB
