Android 监听应用卸载

最近再考虑一个问题，就是监听应用卸载，在卸载360的时候弹出了一个360的网址，很好奇怎么实现的试了好几种方式再Service实时监听log日志，广播都不行，因为卸载了应用程序Service就被停止了。后来再Stackoverflow上面找到了答案，通过底层监听应用目录的变化来实现，下面说说具体得实现方式。

/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
#include 
#include 

#include 
#include 
#include 
#include 
#include 
#include 
#include 

/* 宏定义begin */
//清0宏
#define MEM_ZERO(pDest, destSize) memset(pDest, 0, destSize)

//LOG宏定义
#define LOG_INFO(tag, msg) __android_log_write(ANDROID_LOG_INFO, tag, msg)
#define LOG_DEBUG(tag, msg) __android_log_write(ANDROID_LOG_DEBUG, tag, msg)
#define LOG_WARN(tag, msg) __android_log_write(ANDROID_LOG_WARN, tag, msg)
#define LOG_ERROR(tag, msg) __android_log_write(ANDROID_LOG_ERROR, tag, msg)


/* 内全局变量begin */
static char c_TAG[] = "onEvent";
static jboolean b_IS_COPY = JNI_TRUE;

jstring
Java_com_example_untitled_MyActivity_init( JNIEnv* env,
                                                 jobject thiz )
{
    jstring tag = (*env)->NewStringUTF(env, c_TAG);

    //初始化log
    LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
            , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "init OK"), &b_IS_COPY));

    //fork子进程，以执行轮询任务
    pid_t pid = fork();
    if (pid < 0)
    {
        //出错log
        LOG_ERROR((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "fork failed !!!"), &b_IS_COPY));
    }
    else if (pid == 0)
    {
        //子进程注册"/data/data/pym.test.uninstalledobserver"目录监听器
        int fileDescriptor = inotify_init();
        if (fileDescriptor < 0)
        {
            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                    , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "inotify_init failed !!!"), &b_IS_COPY));

             exit(1);
        }

        int watchDescriptor;
        watchDescriptor = inotify_add_watch(fileDescriptor, "/data/data/com.example.untitled", IN_DELETE);
        if (watchDescriptor < 0)
        {
            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                    , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "inotify_add_watch failed !!!"), &b_IS_COPY));

            exit(1);
        }

        //分配缓存，以便读取event，缓存大小=一个struct inotify_event的大小，这样一次处理一个event
        void *p_buf = malloc(sizeof(struct inotify_event));
        if (p_buf == NULL)
        {
            LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                    , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "malloc failed !!!"), &b_IS_COPY));

            exit(1);
        }
        //开始监听
        LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                    , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "start observer"), &b_IS_COPY));
        size_t readBytes = read(fileDescriptor, p_buf, sizeof(struct inotify_event));

        //read会阻塞进程，走到这里说明收到目录被删除的事件，注销监听器
        free(p_buf);
        inotify_rm_watch(fileDescriptor, IN_DELETE);

        //目录不存在log
        LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
                    , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "uninstalled"), &b_IS_COPY));

        //执行命令am start -a android.intent.action.VIEW -d http://shouji.360.cn/web/uninstall/uninstall.html
       // execlp("am", "am", "start", "-a", "android.intent.action.VIEW", "-d", "http://shouji.360.cn/web/uninstall/uninstall.html", (char *)NULL);
        //4.2以上的系统由于用户权限管理更严格，需要加上 --user 0
       execlp("am", "am", "start","--user", "0" ,"-a", "android.intent.action.VIEW", "-d", "https://www.google.com", (char *)NULL);

    }
    else
    {
        //父进程直接退出，使子进程被init进程领养，以避免子进程僵死
    }

    return (*env)->NewStringUTF(env, "Hello from JNI !");
}

下面是mk文件

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE    := hello-jni
LOCAL_SRC_FILES := hello-jni.c

//因为加了Log日志
LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
LOCAL_LDLIBS += -L$(SYSROOT)/usr/lib -llog

include $(BUILD_SHARED_LIBRARY)

编译SO文件就不多说了，编译成功后将编译好的so文件放在libs目录下

通过调用init方法就可以了