Android NDK – hello catcake

catcake version

catcake-0.9.5-src.tar.gz

Build catcake into a static library with Android NDK

After downloaded the package, then un-zip it into a workspace folder as you wish. To make some work become more easy, I added a env variable named “CATCAKE_ROOT”to point out where my catcake root folder is.

The fist thing that we need to do is to build the catcake project into a static library, so that any other samples could re-use it without need to rebuild it.

To build the static library with Android NDk, I created a file “Application.mk”under $(CATCAKE_ROOT)\project\android\jni.

Application.mk

APP_MODULES      := catcake
APP_PLATFORM     := android-10

For file “Android.mk”(located in the same folder), I modified “LOCAL_C_INCLUDES”part.

LOCAL_C_INCLUDES before modification

LOCAL_C_INCLUDES := \
    apps/catcake/include \
    apps/catcake/source \
    apps/catcake/project/include/zlib \
    apps/catcake/project/include/libpng \
    apps/catcake/project/include/freetype

LOCAL_C_INCLUDES after modification

LOCAL_C_INCLUDES += $(CATCAKE_ROOT)/include
LOCAL_C_INCLUDES += $(CATCAKE_ROOT)/source
LOCAL_C_INCLUDES += $(CATCAKE_ROOT)/project/include/zlib
LOCAL_C_INCLUDES += $(CATCAKE_ROOT)/project/include/libpng
LOCAL_C_INCLUDES += $(CATCAKE_ROOT)/project/include/freetype

Then switch to folder $(CATCAKE_ROOT)\project\android, type in:

> ndk-build –B

If you see something like this, that means you have already successfully build the catcake static library.

The you need to copy following libraries into $(CATCAKE_ROOT)\lib

$(CATCAKE_ROOT)\project\android\obj\local\armeabi\libcatcake.a

$(CATCAKE_ROOT)\project\lib\libfreetype.a libpng.a libz.a

Build hello_catcake sample with NDK

Now that you already have the libcatcake.a file, you could continue the hello_catcake sample. You could find hello_catcake under $(CATCAKE_ROOT)\sample\project\hello_catcake folder. Modify the Android.mk as following to let sample use libcatcake.a and find the header files and other libraries in the correct location.

Android.mk

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)
LOCAL_MODULE := static_catcake
LOCAL_SRC_FILES := ../../../../../lib/libcatcake.a
# LOCAL_EXPORT_C_INCLUDES := $(CATCAKE_ROOT)/include
include $(PREBUILT_STATIC_LIBRARY)

include $(CLEAR_VARS)
LOCAL_MODULE := hello_catcake
LOCAL_SRC_FILES := main.cpp hello_catcake.cpp 
LOCAL_C_INCLUDES := $(CATCAKE_ROOT)/include
LOCAL_CXXFLAGS := -DNDEBUG -DCK_ANDROID
LOCAL_LDLIBS := -L$(CATCAKE_ROOT)/lib -lfreetype -lpng -lz -lGLESv1_CM -lgcc
LOCAL_STATIC_LIBRARIES := static_catcake

include $(BUILD_SHARED_LIBRARY)

If the build process goes smoothly, you will see the information like the following diagram:

Android platform version setting up

One thing that you need to take care about is the Android platform version setting up. There are some place that could set this value, so please make sure all of them use a consistent value.

Application.mk => APP_PLATFORM := android-10

default.properties => target=android-10

project.properties => target=android-15 # eclipse project setting

AndroidManifest.xml => <uses-sdk android:minSdkVersion="10" /> # eclipse project setting

Run hello_catcake from Eclipse

Now you could import the hello_catcake sample into the eclipse, then “Run”-> “Run As Android Application”.

The first time, you run the application, you need to push the application data to emulator with adb push command. This already mentioned in the source code comment part.

ckCreateCatcake("Hello Catcake", 320, 480, 30);

    /*
        The resource files need to be copied to the target by using 'adb push' command like this:
            adb push hello_catcake/data /data/data/catcake_application.hello_catcake/data

        And they must be specified by the absolute paths in ckResMgr::loadResource.
    */
    ckResMgr::loadResource("/data/data/catcake_application.hello_catcake/data/catcake_logo_71x14.png", true);
    ckResMgr::loadResource("/data/data/catcake_application.hello_catcake/data/stonsans.ttf", true);

    newHelloCatcake();