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Fixed bug #859 CREATE_SUBDIRS helps a lot if browsing HTML documentation in a file browser. ALWAYS_DETAILED_SEC makes sure everything has at least the automatic documentation like function prototype and source references. STRIP_FROM_PATH allows you to include only the relevant portions of the files' paths, cleaning up both the file list and directory tree, though you need to change the path listed here to match wherever you put SDL. ALIASES avoids some warnings generated by C:\source\svn.libsdl.org\trunk\SDL\src\joystick\darwin\10.3.9-FIX\IOHIDLib.h. It seems Apple uses a few commands which are not normally supported by Doxygen. BUILTIN_STL_SUPPORT adds support for parsing code which makes use of the standard template library. There isn't a lot of C++ in SDL (some in bwindow at least), but this still seems like a good idea. TYPEDEF_HIDES_STRUCT means that for code like this: typedef struct A {int B;} C; C is documented as a structure containing B instead of a typedef mapped to A. EXTRACT_ALL, EXTRACT_PRIVATE, EXTRACT_STATIC, EXTRACT_LOCAL_METHODS, EXTRACT_ANON_NSPACES and INTERNAL_DOCS make sure that _everything_ is documented. CASE_SENSE_NAMES = NO avoids potential conflicts when building documentation on case insensitive file systems like NTFS and FAT32. WARN_NO_PARAMDOC lets you know when you have documented some, but not all, of the parameters of a function. This is useful when you're working on adding such documentation since it makes partially documented functions easier to spot. WARN_LOGFILE writes warnings to a seperate file instead of mixing them in with stdout. When not running in quiet mode, these warnings can be hard to spot without this flag. I added *.h.in and *.h.default to FILE_PATTERNS to generate documentation for config.h.in and config.h.default. RECURSIVE tells doxygen to look not only in the input directory, but also in subfolders. EXCLUDE avoids documenting things like test programs, examples and templates which need to be documented separately. I've used EXCLUDE_PATTERNS to exclude non-source subdirectories that often find their way into source folders (such as obj or .svn). EXAMPLE_PATH lists directories doxygen will search to find included example code. So far, SDL doesn't really use this feature, but I've listed some likely locations. SOURCE_BROWSER adds syntax highlighted source code to the HTML output. USE_HTAGS is nice, but not available on Windows. INLINE_SOURCES adds the body of a function to it's documentation so you can quickly see exactly what it does. ALPHABETICAL_INDEX generates an alphabetical list of all structures, functions, etc., which makes it much easier to find what you're looking for. IGNORE_PREFIX skips the SDL_ prefix when deciding which index page to place an item on so you don't have everything show up under "S". HTML_DYNAMIC_SECTIONS hides the includes/included by diagrams by default and adds JavaScript to allow the user to show and hide them by clicking a link. ENUM_VALUES_PER_LINE = 1 makes enums easier to read by placing each value on it's own line. GENERATE_TREEVIEW produces a two frame index page with a navigation tree on the left. I have LaTeX and man pages turned off to speed up doxygen, you may want to turn them back on yourself. I added _WIN32=1 to PREDEFINED to cause SDL to output documentation related to Win32 builds of SDL. Normally, doxygen gets confused since there are multiple definitions for various structures and formats that vary by platform. Without this doxygen can produce broken documentation or, if you're lucky, output documentation only for the dummy drivers, which isn't very useful. You need to pick a platform. GENERATE_TAGFILE produces a file which can be used to link other doxygen documentation to the SDL documentation. CLASS_DIAGRAMS turns on class diagrams even when dot is not available. HAVE_DOT tells doxygen to try to use dot to generate diagrams. TEMPLATE_RELATIONS and INCLUDE_GRAPH add additional diagrams to the documentation. DOT_MULTI_TARGETS speeds up dot. OUTPUT_DIRECTORY, INPUT and other paths reflect the fact that this Doxyfile is intended to process src as well as include and is being run from a separate subdirectory. Doxygen produces several temporary files while it's running and if interrupted, can leave those files behind. It's easier to clean up if there aren't a hundred or so files in the same folder. I typically run doxygen in SDL/doxy and set the output directory to '.'. Since doxygen puts it's output in subfolders by type, this keeps things pretty well organised. You could use '../doc' instead and get the same results.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 21 Jan 2011 12:57:01 -0800
parents 3811132c584f
children
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================================================================================
Simple DirectMedia Layer for Android
================================================================================

Requirements:

Android SDK
http://developer.android.com/sdk/index.html

Android NDK r4 or later
http://developer.android.com/sdk/ndk/index.html


================================================================================
 How the port works
================================================================================

- Android applications are Java-based, optionally with parts written in C
- As SDL apps are C-based, we use a small Java shim that uses JNI to talk to 
the SDL library
- This means that your application C code must be placed inside an android 
Java project, along with some C support code that communicates with Java
- This eventually produces a standard Android .apk package

The Android Java code implements an "activity" and can be found in:
android-project/src/org/libsdl/app/SDLActivity.java

The Java code loads your game code, the SDL shared library, and
dispatches to native functions implemented in the SDL library:
src/SDL_android.cpp

Your project must include some glue code that starts your main() routine:
src/main/android/SDL_android_main.cpp


================================================================================
 Building an app
================================================================================

Instructions:
1. Copy the android-project directory wherever you want to keep your projects and rename it to the name of your project.
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)

Here's an explanation of the files in the Android project, so you can customize them:

android-project/
	AndroidManifest.xml	- package manifest, do not modify
	build.properties	- empty
	build.xml		- build description file, used by ant
	default.properties	- holds the ABI for the application, currently android-4 which corresponds to the Android 1.6 system image
	local.properties	- holds the SDK path, you should change this to the path to your SDK
	jni/			- directory holding native code
	jni/Android.mk		- Android makefile that includes all subdirectories
	jni/SDL/		- directory holding the SDL library files
	jni/SDL/Android.mk	- Android makefile for creating the SDL shared library
	jni/src/		- directory holding your C/C++ source
	jni/src/Android.mk	- Android makefile that you should customize to include your source code and any library references
	res/			- directory holding resources for your application
	res/drawable-*		- directories holding icons for different phone hardware
	res/layout/main.xml	- place holder for the main screen layout, overridden by the SDL video output
	res/values/strings.xml	- strings used in your application, including the application name shown on the phone.
	src/org/libsdl/app/SDLActivity.java	- the Java class handling the initialization and binding to SDL.  Be very careful changing this, as the SDL library relies on this implementation.


================================================================================
 Additional documentation
================================================================================

The documentation in the NDK docs directory is very helpful in understanding the build process and how to work with native code on the Android platform.

The best place to start is with docs/OVERVIEW.TXT


================================================================================
 Using Eclipse
================================================================================

First make sure that you've installed Eclipse and the Android extensions as described here:
	http://developer.android.com/sdk/eclipse-adt.html

Once you've copied the SDL android project and customized it, you can create an Eclipse project from it:
 * File -> New -> Other
 * Select the Android -> Android Project wizard and click Next
 * Enter the name you'd like your project to have
 * Select "Create project from existing source" and browse for your project directory
 * Make sure the Build Target is set to Android 1.6
 * Click Finish


================================================================================
 Loading files and resources
================================================================================

NEED CONTENT


================================================================================
 Troubleshooting
================================================================================

You can create and run an emulator from the Eclipse IDE:
 * Window -> Android SDK and AVD Manager

You can see if adb can see any devices with the following command:
	adb devices

You can see the output of log messages on the default device with:
	adb logcat

You can push files to the device with:
	adb push local_file remote_path_and_file

You can push files to the SD Card at /sdcard, for example:
	adb push moose.dat /sdcard/moose.dat

You can see the files on the SD card with a shell command:
	adb shell ls /sdcard/

You can start a command shell on the default device with:
	adb shell

You can do a clean build with the following commands:
	ndk-build clean
	ndk-build

You can see the complete command line that ndk-build is using by passing V=1 on the command line:
	ndk-build V=1

If your application crashes in native code, you can use addr2line to convert the addresses in the stack trace to lines in your code.

For example, if your crash looks like this:
I/DEBUG   (   31): signal 11 (SIGSEGV), code 2 (SEGV_ACCERR), fault addr 400085d0
I/DEBUG   (   31):  r0 00000000  r1 00001000  r2 00000003  r3 400085d4
I/DEBUG   (   31):  r4 400085d0  r5 40008000  r6 afd41504  r7 436c6a7c
I/DEBUG   (   31):  r8 436c6b30  r9 435c6fb0  10 435c6f9c  fp 4168d82c
I/DEBUG   (   31):  ip 8346aff0  sp 436c6a60  lr afd1c8ff  pc afd1c902  cpsr 60000030
I/DEBUG   (   31):          #00  pc 0001c902  /system/lib/libc.so
I/DEBUG   (   31):          #01  pc 0001ccf6  /system/lib/libc.so
I/DEBUG   (   31):          #02  pc 000014bc  /data/data/org.libsdl.app/lib/libmain.so
I/DEBUG   (   31):          #03  pc 00001506  /data/data/org.libsdl.app/lib/libmain.so

You can see that there's a crash in the C library being called from the main code.  I run addr2line with the debug version of my code:
	arm-eabi-addr2line -C -f -e obj/local/armeabi/libmain.so
and then paste in the number after "pc" in the call stack, from the line that I care about:
000014bc

I get output from addr2line showing that it's in the quit function, in testspriteminimal.c, on line 23.

You can add logging to your code to help show what's happening:

#include <android/log.h>

	__android_log_print(ANDROID_LOG_INFO, "foo", "Something happened! x = %d", x);

If you need to build without optimization turned on, you can create a file called "Application.mk" in the jni directory, with the following line in it:
APP_OPTIM := debug


================================================================================
 Known issues
================================================================================

- SDL audio (although it's mostly written, just not working properly yet)
- TODO. I'm sure there's a bunch more stuff I haven't thought of