Build the SDL library as a shared object on Android, so it will work correctly...

Build the SDL library as a shared object on Android, so it will work correctly with SDL_image and SDL_ttf.

Android.mk

+LOCAL_PATH := $(call my-dir)
+
+###########################
+#
+# SDL shared library
+#
+###########################
+
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := SDL
+
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
+
+LOCAL_SRC_FILES := src/SDL_android.cpp \
+	$(subst $(LOCAL_PATH)/,, \
+	$(wildcard $(LOCAL_PATH)/src/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/audio/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/cpuinfo/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/events/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/file/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/joystick/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/haptic/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/stdlib/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/thread/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/timer/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/video/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/power/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/audio/android/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/audio/dummy/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/video/android/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/joystick/android/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/haptic/dummy/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/atomic/dummy/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/thread/pthread/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/timer/unix/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/loadso/dlopen/*.c))
+
+LOCAL_LDLIBS := -ldl -lGLESv1_CM -llog
+
+include $(BUILD_SHARED_LIBRARY)

Makefile.android

-# Makefile to build the SDL library
-
-include ./android/config.cfg #get ANDROID_NDK, ANDROID_NDK_HOST
-
-# For NDK R4
-TOOLS_PATH=$(ANDROID_NDK)/build/prebuilt/$(ANDROID_NDK_HOST)/arm-eabi-4.2.1/bin
-ANDROID_INCLUDES = -I$(ANDROID_NDK)/build/platforms/android-4/arch-arm/usr/include 
-
-# For NDK R5
-#TOOLS_PATH=$(ANDROID_NDK)/toolchains/arm-eabi-4.4.0/prebuilt/$(ANDROID_NDK_HOST)/bin
-#ANDROID_INCLUDES = -I$(ANDROID_NDK)/platforms/android-4/arch-arm/usr/include 
-
-INCLUDE = -I./include
-CFLAGS  = -g -O2 -fno-short-enums $(INCLUDE) $(ANDROID_INCLUDES) -DANDROID -DANDROID_NDK -static
-
-AR	= $(TOOLS_PATH)/arm-eabi-ar
-RANLIB	= $(TOOLS_PATH)/arm-eabi-ranlib
-CC = $(TOOLS_PATH)/arm-eabi-gcc
-
-
-CONFIG_H = include/SDL_config.h
-TARGET  = libSDL.a
-SOURCES = \
-	src/*.c \
-	src/audio/*.c \
-	src/cpuinfo/*.c \
-	src/events/*.c \
-	src/file/*.c \
-	src/joystick/*.c \
-	src/haptic/*.c \
-	src/stdlib/*.c \
-	src/thread/*.c \
-	src/timer/*.c \
-	src/video/*.c \
-	src/power/*.c \
-	src/audio/android/*.c \
-	src/audio/dummy/*.c \
-	src/video/android/*.c \
-	src/joystick/android/*.c \
-	src/haptic/dummy/*.c \
-	src/atomic/dummy/*.c \
-	src/thread/pthread/*.c \
-	src/timer/unix/*.c \
-	src/loadso/dummy/*.c \
-
-OBJECTS = $(shell echo $(SOURCES) | sed -e 's,\.c,\.o,g')
-
-all: $(TARGET)
-
-$(TARGET): $(CONFIG_H) $(OBJECTS)
-	$(AR) crv $@ $^
-	$(RANLIB) $@
-
-$(CONFIG_H):
-	cp $(CONFIG_H).default $(CONFIG_H)
-
-clean:
-	rm -f $(TARGET) $(OBJECTS)

README.android

@@ -2,7 +2,8 @@
 Simple DirectMedia Layer for Android
 ================================================================================
 
-Requirements: Android NDK r4 or later
+Requirements: Android SDK and Android NDK r4 or later
+http://developer.android.com/
 
 ================================================================================
  How the port works
@@ -16,26 +17,44 @@ Java project, along with some C support code that communicates with Java
 - This eventually produces a standard Android .apk package
 
 
+================================================================================
+ Building an app
+================================================================================
 
+Instructions:
+1. Copy the android-project directory wherever you want your Android project to go
+2. Move this SDL directory into the <project>/jni directory
+3. Place your application source files in the <project>/jni/src directory
+4. Edit <project>/jni/src/Android.mk to include your source files
+5. Run 'ndk-build' (a script provided by the NDK). This compiles the C source
 
+If you want to use the Eclipse IDE, skip to the Eclipse section below.
+
+6. Edit <project>/local.properties to point to the Android SDK directory
+7. Run 'ant debug' in android/project. This compiles the .java and eventually 
+creates a .apk with the native code embedded
+8. 'ant install' will push the apk to the device or emulator (if connected)
 
 
 ================================================================================
- Building an app
+ Using Eclipse
 ================================================================================
 
-Instructions:
-1. Edit android/config.cfg to point to the location of the NDK
-2. Run 'make -f Makefile.android'. If all goes well, libsdl.a should be created
-3. Place your application source files in android/project/jni
-4. Edit the Android.mk to include your source files
-5. Run 'ndk-build' (a script provided by the NDK). This compiles the C source
-6. Edit project/local.properties to point to the SDK directory
-6. Run 'ant debug' in android/project. This compiles the .java and eventually 
-creates a .apk with the C source embedded
-7. 'ant install' will push the apk to the device or emulator (if connected)
+NEED CONTENT
 
 
+================================================================================
+ Loading files
+================================================================================
+
+NEED CONTENT
+
+
+================================================================================
+ Troubleshooting
+================================================================================
+
+NEED CONTENT
 
 
 ================================================================================

android/config.cfg.example

-# This file sets up paths needed to find the NDK build tools.
-# Edit it appropriately for your configuration and save it as "config.cfg".
-
-# This should be the full path to the Android NDK
-ANDROID_NDK := /Users/hercules/eclipse/android-ndk-r5
-
-# This should be "linux-x86" for linux, "darwin-x86" for mac
-ANDROID_NDK_HOST := darwin-x86

android/project/AndroidManifest.xml

-<?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-      package="org.libsdl.app"
-      android:versionCode="1"
-      android:versionName="1.0">
-    <application android:label="@string/app_name" android:icon="@drawable/icon">
-        <activity android:name="SDLActivity"
-                  android:label="@string/app_name">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.LAUNCHER" />
-            </intent-filter>
-        </activity>
-    </application>
-</manifest> 

android/project/build.properties

-# This file is used to override default values used by the Ant build system.
-# 
-# This file must be checked in Version Control Systems, as it is
-# integral to the build system of your project.
-
-# This file is only used by the Ant script.
-
-# You can use this to override default values such as
-#  'source.dir' for the location of your java source folder and
-#  'out.dir' for the location of your output folder.
-
-# You can also use it define how the release builds are signed by declaring
-# the following properties:
-#  'key.store' for the location of your keystore and
-#  'key.alias' for the name of the key to use.
-# The password will be asked during the build when you use the 'release' target.
-

android/project/build.xml

-<?xml version="1.0" encoding="UTF-8"?>
-<project name="SDLApp" default="help">
-
-    <!-- The local.properties file is created and updated by the 'android' tool.
-         It contains the path to the SDK. It should *NOT* be checked in in Version
-         Control Systems. -->
-    <property file="local.properties" />
-
-    <!-- The build.properties file can be created by you and is never touched
-         by the 'android' tool. This is the place to change some of the default property values
-         used by the Ant rules.
-         Here are some properties you may want to change/update:
-
-         application.package
-             the name of your application package as defined in the manifest. Used by the
-             'uninstall' rule.
-         source.dir
-             the name of the source directory. Default is 'src'.
-         out.dir
-             the name of the output directory. Default is 'bin'.
-
-         Properties related to the SDK location or the project target should be updated
-          using the 'android' tool with the 'update' action.
-
-         This file is an integral part of the build system for your application and
-         should be checked in in Version Control Systems.
-
-         -->
-    <property file="build.properties" />
-
-    <!-- The default.properties file is created and updated by the 'android' tool, as well
-         as ADT.
-         This file is an integral part of the build system for your application and
-         should be checked in in Version Control Systems. -->
-    <property file="default.properties" />
-
-    <!-- Custom Android task to deal with the project target, and import the proper rules.
-         This requires ant 1.6.0 or above. -->
-    <path id="android.antlibs">
-        <pathelement path="${sdk.dir}/tools/lib/anttasks.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/sdklib.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/androidprefs.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/apkbuilder.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/jarutils.jar" />
-    </path>
-
-    <taskdef name="setup"
-        classname="com.android.ant.SetupTask"
-        classpathref="android.antlibs" />
-
-    <!-- Execute the Android Setup task that will setup some properties specific to the target,
-         and import the build rules files.
-
-         The rules file is imported from
-            <SDK>/platforms/<target_platform>/templates/android_rules.xml
-
-         To customize some build steps for your project:
-         - copy the content of the main node <project> from android_rules.xml
-         - paste it in this build.xml below the <setup /> task.
-         - disable the import by changing the setup task below to <setup import="false" />
-
-         This will ensure that the properties are setup correctly but that your customized
-         build steps are used.
-    -->
-    <setup />
-
-</project>

android/project/default.properties

-# This file is automatically generated by Android Tools.
-# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
-# 
-# This file must be checked in Version Control Systems.
-# 
-# To customize properties used by the Ant build system use,
-# "build.properties", and override values to adapt the script to your
-# project structure.
-
-# Project target.
-target=android-4

android/project/jni/Android.mk

-LOCAL_PATH := $(call my-dir)
-
-include $(CLEAR_VARS)
-
-LOCAL_MODULE := sdlapp
-SDL := ../../../
-
-LOCAL_CFLAGS := -DANDROID_NDK \
-                -DDISABLE_IMPORTGL \
-                -I$(SDL)/include
-
-LOCAL_SRC_FILES := \
-    android-support.cpp \
-    lesson05.c \
-
-LOCAL_LDLIBS := -lGLESv1_CM -ldl -llog -lSDL -lgcc -L$(SDL)
-
-include $(BUILD_SHARED_LIBRARY)

android/project/local.properties

-# This file is automatically generated by Android Tools.
-# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
-# 
-# This file must *NOT* be checked in Version Control Systems,
-# as it contains information specific to your local configuration.
-
-# location of the SDK. This is only used by Ant
-# For customization when using a Version Control System, please read the
-# header note.
-sdk.dir=/home/paul/Projects/gsoc/sdk/android-sdk-linux_86

android/project/res/layout/main.xml

-<?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:orientation="vertical"
-    android:layout_width="fill_parent"
-    android:layout_height="fill_parent"
-    >
-<TextView  
-    android:layout_width="fill_parent" 
-    android:layout_height="wrap_content" 
-    android:text="Hello World, SDLActivity"
-    />
-</LinearLayout>
-

android/project/res/values/strings.xml

-<?xml version="1.0" encoding="utf-8"?>
-<resources>
-    <string name="app_name">SDLActivity</string>
-</resources>

include/SDL_config_android.h

@@ -127,7 +127,7 @@ typedef unsigned int size_t;
 #define SDL_HAPTIC_DUMMY	1
 
 /* Enable various shared object loading systems */
-#define SDL_LOADSO_DUMMY	1
+#define SDL_LOADSO_DLOPEN	1
 
 /* Enable various threading systems */
 #define SDL_THREAD_PTHREAD	1

android/project/jni/android-support.cpp → src/SDL_android.cpp

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997-2010 Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+#include "SDL_config.h"
+
 /*******************************************************************************
  This file links the Java side of Android with libsdl
 *******************************************************************************/
 #include <jni.h>
-#include <sys/time.h>
-#include <time.h>
 #include <android/log.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
-#include <pthread.h>
-
-#define DEBUG
 
 
 /*******************************************************************************
                                Globals
 *******************************************************************************/
-static long _getTime(void){
-	struct timeval  now;
-	gettimeofday(&now, NULL);
-	return (long)(now.tv_sec*1000 + now.tv_usec/1000);
-}
-
+JavaVM* mVM = NULL;
 JNIEnv* mEnv = NULL;
 JNIEnv* mAudioThreadEnv = NULL; //See the note below for why this is necessary
-JavaVM* mVM = NULL;
 
 //Main activity
 jclass mActivityInstance;
@@ -36,7 +44,6 @@ jmethodID midFlipBuffers;
 jmethodID midEnableFeature;
 jmethodID midUpdateAudio;
 
-extern "C" int SDL_main(int argc, char *argv[]);
 extern "C" int Android_OnKeyDown(int keycode);
 extern "C" int Android_OnKeyUp(int keycode);
 extern "C" void Android_SetScreenResolution(int width, int height);
@@ -59,19 +66,20 @@ float fLastAccelerometer[3];
                  Functions called by JNI
 *******************************************************************************/
 
-//Library init
-extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved){
+// Library init
+extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved)
+{
+    mVM = vm;
 
-    JNIEnv* env = NULL;
-    jint result = -1;
-
-    if (vm->GetEnv((void**) &env, JNI_VERSION_1_4) != JNI_OK) {
-        return result;
-    }
+    return JNI_VERSION_1_4;
+}
 
+// Called before SDL_main() to initialize JNI bindings
+extern "C" void SDL_Android_Init(JNIEnv* env)
+{
     mEnv = env;
 
-    __android_log_print(ANDROID_LOG_INFO, "SDL", "JNI: OnLoad");
+    __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL_Android_Init()");
 
     jclass cls = mEnv->FindClass ("org/libsdl/app/SDLActivity"); 
     mActivityInstance = cls;
@@ -81,62 +89,41 @@ extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved){
     midUpdateAudio = mEnv->GetStaticMethodID(cls,"updateAudio","([B)V");
 
     if(!midCreateGLContext || !midFlipBuffers || !midEnableFeature ||
-        !midUpdateAudio){
+        !midUpdateAudio) {
         __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: Bad mids\n");
-    }else{
+    } else {
 #ifdef DEBUG
         __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: Good mids\n");
 #endif
     }
-    
-    return JNI_VERSION_1_4;
 }
 
-//Start up the SDL app
-extern "C" void Java_org_libsdl_app_SDLActivity_nativeInit( JNIEnv* env, 
-                                                                jobject obj ){ 
-                                                                   
-	__android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: Native Init");
-
-	mEnv = env;
-	bRenderingEnabled = true;
-
-	Android_EnableFeature(FEATURE_ACCEL, true);
-
-    char *argv[2];
-    argv[0] = strdup("SDL_app");
-    argv[1] = NULL;
-    SDL_main(1, argv);
-}
-
-//Keydown
+// Keydown
 extern "C" void Java_org_libsdl_app_SDLActivity_onNativeKeyDown(JNIEnv* env, 
-               jobject obj, jint keycode){
-    
+               jobject obj, jint keycode)
+{
     int r = Android_OnKeyDown(keycode);
 #ifdef DEBUG
     __android_log_print(ANDROID_LOG_INFO, "SDL", 
                         "SDL: native key down %d, %d\n", keycode, r);
 #endif
-                        
 }
 
-//Keyup
+// Keyup
 extern "C" void Java_org_libsdl_app_SDLActivity_onNativeKeyUp(JNIEnv* env, 
-               jobject obj, jint keycode){
-    
+               jobject obj, jint keycode)
+{
     int r = Android_OnKeyUp(keycode);
 #ifdef DEBUG
     __android_log_print(ANDROID_LOG_INFO, "SDL", 
                         "SDL: native key up %d, %d\n", keycode, r);
 #endif
-                        
 }
 
-//Touch
+// Touch
 extern "C" void Java_org_libsdl_app_SDLActivity_onNativeTouch(JNIEnv* env, 
-               jobject obj, jint action, jfloat x, jfloat y, jfloat p){
-
+               jobject obj, jint action, jfloat x, jfloat y, jfloat p)
+{
 #ifdef DEBUG
     __android_log_print(ANDROID_LOG_INFO, "SDL", 
                         "SDL: native touch event %d @ %f/%f, pressure %f\n", 
@@ -144,42 +131,40 @@ extern "C" void Java_org_libsdl_app_SDLActivity_onNativeTouch(JNIEnv* env,
 #endif
 
     //TODO: Pass this off to the SDL multitouch stuff
-                        
 }
 
-//Quit
+// Quit
 extern "C" void Java_org_libsdl_app_SDLActivity_nativeQuit( JNIEnv*  env, 
-                                                                jobject obj ){    
-
-    //Stop rendering as we're no longer in the foreground
+                                                                jobject obj )
+{    
+    // Stop rendering as we're no longer in the foreground
     bRenderingEnabled = false;
 
-    //Inject a SDL_QUIT event
-    int r = SDL_SendQuit();
-
-    __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: Native quit %d", r);        
+    // Inject a SDL_QUIT event
+    SDL_SendQuit();
 }
 
-//Screen size
+// Screen size
 extern "C" void Java_org_libsdl_app_SDLActivity_nativeSetScreenSize(
-                JNIEnv*  env, jobject obj, jint width, jint height){
-
+                JNIEnv*  env, jobject obj, jint width, jint height)
+{
     __android_log_print(ANDROID_LOG_INFO, "SDL", 
                         "SDL: Set screen size on init: %d/%d\n", width, height);
     Android_SetScreenResolution(width, height);
-                        
 }
 
-//Resize
+// Resize
 extern "C" void Java_org_libsdl_app_SDLActivity_onNativeResize(
                                         JNIEnv*  env, jobject obj, jint width, 
-                                        jint height, jint format){
+                                        jint height, jint format)
+{
     Android_OnResize(width, height, format);
 }
 
 extern "C" void Java_org_libsdl_app_SDLActivity_onNativeAccel(
                                         JNIEnv*  env, jobject obj,
-                                        jfloat x, jfloat y, jfloat z){
+                                        jfloat x, jfloat y, jfloat z)
+{
     fLastAccelerometer[0] = x;
     fLastAccelerometer[1] = y;
     fLastAccelerometer[2] = z;   
@@ -190,7 +175,8 @@ extern "C" void Java_org_libsdl_app_SDLActivity_onNativeAccel(
 /*******************************************************************************
              Functions called by SDL into Java
 *******************************************************************************/
-extern "C" void Android_CreateContext(){
+extern "C" void Android_CreateContext()
+{
     __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: sdl_create_context()\n");
 
     bRenderingEnabled = true;
@@ -198,30 +184,30 @@ extern "C" void Android_CreateContext(){
     mEnv->CallStaticVoidMethod(mActivityInstance, midCreateGLContext ); 
 }
 
-extern "C" void Android_Render(){
-
-    if(!bRenderingEnabled){
+extern "C" void Android_Render()
+{
+    if (!bRenderingEnabled) {
         return;
     }
 
-    //When we get here, we've accumulated a full frame    
-    mEnv->CallStaticVoidMethod(mActivityInstance, midFlipBuffers ); 
+    // When we get here, we've accumulated a full frame    
+    mEnv->CallStaticVoidMethod(mActivityInstance, midFlipBuffers); 
 }
 
-extern "C" void Android_EnableFeature(int featureid, bool enabled){
-
+extern "C" void Android_EnableFeature(int featureid, bool enabled)
+{
     mEnv->CallStaticVoidMethod(mActivityInstance, midEnableFeature, 
                                 featureid, (int)enabled); 
 }
 
-extern "C" void Android_UpdateAudioBuffer(unsigned char *buf, int len){
-
+extern "C" void Android_UpdateAudioBuffer(unsigned char *buf, int len)
+{
     //Annoyingly we can't just call into Java from any thread. Because the audio
     //callback is dispatched from the SDL audio thread (that wasn't made from
     //java, we have to do some magic here to let the JVM know about the thread.
     //Because everything it touches on the Java side is static anyway, it's 
     //not a big deal, just annoying.
-    if(!mAudioThreadEnv){
+    if(!mAudioThreadEnv) {
         __android_log_print(ANDROID_LOG_INFO, "SDL", "SDL: Need to set up audio thread env\n");
 
         mVM->AttachCurrentThread(&mAudioThreadEnv, NULL);

src/main/android/SDL_android_main.cpp

+
+/* Include the SDL main definition header */
+#include "SDL_main.h"
+
+/*******************************************************************************
+                 Functions called by JNI
+*******************************************************************************/
+#include <jni.h>
+
+// Called before SDL_main() to initialize JNI bindings in SDL library
+extern "C" void SDL_Android_Init(JNIEnv* env);
+
+// Library init
+extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved)
+{
+    return JNI_VERSION_1_4;
+}
+
+// Start up the SDL app
+extern "C" void Java_org_libsdl_app_SDLActivity_nativeInit( JNIEnv* env, jobject obj )
+{
+    /* This interface could expand with ABI negotiation, calbacks, etc. */
+    SDL_Android_Init(env);
+
+    /* Run the application code! */
+    char *argv[2];
+    argv[0] = strdup("SDL_app");
+    argv[1] = NULL;
+    SDL_main(1, argv);
+}