Sunday, August 14, 2011

How to build Android ndk sample using ant

This is a walkthrough of how to build the hello-jni sample from Android ndk after you have installed sdk and ndk. You want to use ant instead of Eclipse for building sample project.

Suppose your install paths of sdk and ndk are
~/android-sdk-mac_x86 and ~/android-ndk-r5c

Setup PATH
export PATH=${PATH}:~/android-sdk-mac_x86/tools:~/android-ndk-r5c

Please take note that for Mac OSX Mavericks, ant is no longer in Mac, just download a binary distribution of Ant from . Just download it, unzip/untar it, and add its bin directory to your PATH. say export PATH=${PATH}:~/apache-ant-1.9.4/bin

cd ~/android-ndk-r5c/samples/hello-jni

list target (assume sdk installed)
android list target

update project with target 1
android update project -t 1 -p .

list avd (suppose AVD4G created during sdk installation)
android list avd

start emulator
emulator -avd AVD4G -scale 0.5 &

#if you have Samsung Galaxy skin (download here)
emulator -avd AVD4G -skin GALAXY_Tab -scale 0.5 &

debug build
ant debug

install to emulator
ant debug install

use ant uninstall to remove

If you want to code-sign the binary, first create the and self-signing certificate and compile release


# location of the keystore. This is used by ant release /my-path-to-mykey/my.keystore

create self-signing certificate and compile release
keytool -genkey -v -keystore /my-path-to-mykey/my.keystore -alias mykeystore -keyalg RSA -keysize 2048 -validity 10000
ant release

This is how to compile C++ program with stlport in ndk

cd ~/android-ndk-r5c/samples/test-libstdc++

modify jni/test-libstl.cpp to
jni/test-libstl.cpp    Select all
#include <iostream> using namespace std; int main() {   cout << "hello, world\n";   return 0; }

create jni/ with
APP_STL := stlport_static

modify jni/ with
jni/    Select all
LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) LOCAL_MODULE := test-libstl LOCAL_SRC_FILES := test-libstl.cpp LOCAL_LDLIBS := -llog include $(BUILD_EXECUTABLE) include $(CLEAR_VARS) LOCAL_EXECUTABLE := test-libstl run:     ~/android-sdk-mac_x86/platform-tools/adb push libs/armeabi/$(LOCAL_MODULE) /data/local/bin/$(LOCAL_MODULE)     ~/android-sdk-mac_x86/platform-tools/adb shell chmod 755 /data/local/bin/$(LOCAL_MODULE)     ~/android-sdk-mac_x86/platform-tools/adb shell /data/local/bin/$(LOCAL_MODULE) # makefile requires the use of tab for the indented spaces above

run with emulator

cd ~/android-ndk-r5c/samples/test-libstdc++
ndk-build clean && ndk-build
ndk-build run

For Windows, add this PATH in environment (path should not have spaces)

JAVA_HOME=C:\Program Files\Java\jdk1.6.0_29

and you need cygwin to start ndk-build

1 comment:

David said...

Cool stuff, works too!