如何在Android中写和使用一个自定义的java库

1，定义一个Android.mk
================
LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

MAINLIB_ABS_SRC_DIR := $(LOCAL_PATH)/../
MAINLIB_SRC_DIR := ..

src_files:=$(call all-java-files-under,$(MAINLIB_SRC_DIR))
aidl_files:=$(call all-Iaidl-files-under,$(MAINLIB_SRC_DIR))

LOCAL_SRC_FILES := \
    $(src_files) \
    $(aidl_files)

LOCAL_AIDL_INCLUDES :=  \
    $(MAINLIB_ABS_SRC_DIR)/sensors/java \
    $(MAINLIB_ABS_SRC_DIR)/webkit/java \
    $(MAINLIB_ABS_SRC_DIR)/ui/java

LOCAL_MODULE:= com.xxx.android.frameworks

LOCAL_MODULE_CLASS := JAVA_LIBRARIES

LOCAL_DX_FLAGS := --core-library

#include R.java of resource apk
LOCAL_INTERMEDIATE_SOURCES := $(framework-res-source-path)/my/own/
resource/apk/R.java

include $(BUILD_JAVA_LIBRARY)
==============================

2, 在com/xxx/android/frameworks下开发java库；

3，库的资源作为一个apk的Android.mk
==============================
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)

LOCAL_PACKAGE_NAME := my-lib-res
LOCAL_CERTIFICATE := platform

# Tell aapt to create "extending (non-application)" resource IDs,
LOCAL_AAPT_FLAGS := -x

LOCAL_MODULE_TAGS := user

# Install this alongside the libraries.
LOCAL_MODULE_PATH := $(TARGET_OUT_JAVA_LIBRARIES)

# Create package-export.apk, which other packages can use to get
# PRODUCT-agnostic resource data like IDs and type definitions.
LOCAL_EXPORT_PACKAGE_RESOURCES := true

include $(BUILD_PACKAGE)
===========================================

4，资源apk的AndroidManifest.xml

      package="com.abc.android.widget">

红字是在自定义库(com.xxx.android.frameworks.jar)中的包名。

5，在attrs.xml中自定义widget的style

       
       
       
        .....


6, 在widget文件中
public MyWidgeFlowView(Context context, AttributeSet attrSet, int defStyle) {
        super(context, attrSet, defStyle);

        TypedArray a = context.obtainStyledAttributes(attrSet,
                R.styleable.WidgeFlowView, defStyle, 0);
        mIsMainItemLive = a.getBoolean(R.styleable.WidgeFlowView_isMainItemLive, false);
        mMainItemWidth = a.getDimensionPixelSize(R.styleable.WidgetFlowView_mainItemWidth, 256);
        ....
        a.recycle();
}

5，make编译,结果在com.xxx.android.frameworks.jar

如何使用
1，在AndroidManifest.xml中加入


2，如果在layout文件中用到自定义库中的类

        xmlns:abc.res="com.abc.android.widget"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:background="@drawable/card_wall"
        android:orientation="vertical">
....
        <com.abc.android.widget.XXXView android:id="@+id/widget_id"
                       android:layout_width="fill_parent"
                       android:layout_height="fill_parent"
                       android:layout_weight="0"
                       abc.res:mainItemWidth="185dip"
                       abc.res:mainItemHeight="185dip"
                       abc.res:mainItemOffsetY="-10dip"/>
       

红字是widget在自定义库中的包名

3，在java文件中用要
import com.abc.android.widget.XXXView;