Android应用如何监听自己是否被卸载及卸载反馈功能的实现

  一个应用被用户卸载肯定是有理由的,而开发者却未必能得知这一重要的理由,毕竟用户很少会主动反馈建议,多半就是用得不爽就卸,如果能在被卸载后获取到用户的一些反馈,那对开发者进一步改进应用是非常有利的。目前据我所知,国内的Android应用中实现这一功能的只有360手机卫士、360平板卫士,那么如何实现这一功能的?

  我们可以把实现卸载反馈的问题转化为监听自己是否被卸载,只有得知自己被卸载,才可以设计相应的反馈处理流程。以下的列表是我在研究这一问题的思路:

  1,注册BroadcastReceiver,监听"android.intent.action.PACKAGE_REMOVED"系统广播

  结果:NO。未写代码,直接分析,卸载的第一步就是退出当前应用的主进程,而此广播是在已经卸载完成后才发出的,此时主进程都没有了,去哪onReceive()呢?

  2,若能收到"将要卸载XX包"的系统广播,在主进程被退出之前就抢先进行反馈处理就好了,可惜没有这样的系统广播,不过经过调研,倒是发现了一个办法,读取系统log,当日志中包含"android.intent.action.DELETE"和自己的包名时,意味着自己将要被卸载。

  结果:NO。调试时发现此方法有两个缺陷,(1)点击设置中的卸载按钮即发出此Intent,此时用户尚未在弹框中确认卸载;(2)pm命令卸载不出发此Intent,意味着被诸如手机安全管家,豌豆荚等软件卸载时,无法提前得知卸载意图。

  3,由于时间点不容易把控,所以干脆不依赖系统广播或log,考虑到卸载过程会删除"/data/data/包名"目录,我们可以用线程直接轮询这个目录是否存在,以此为依据判断自己是否被卸载。

  结果:NO。同方法1,主进程退出,相应的线程必定退出,线程还没等到判断目录是否存在就已经被销毁了。

  4,改用C端进程轮询"/data/data/包名"目录是否存在

  结果:YES。借助Java端进程fork出来的C端进程在应用被卸载后不会被销毁。

  OK,上代码!

Activity启动时fork出C端进程轮询目录:

 1 package main.activity;
 2 
 3 import pym.test.uninstalledmoniter.R;
 4 import android.app.Activity;
 5 import android.os.Bundle;
 6 import android.util.Log;
 7 
 8 /**
 9  * @author pengyiming
10  * @note 监听此应用是否被卸载,若被卸载则弹出卸载反馈
11  *
12  */
13 
14 public class UninstalledMoniterActivity extends Activity
15 {
16     /* 数据段begin */
17     private static final String TAG = "UninstalledMoniterActivity";
18     /* 数据段end */
19     
20     /* 函数段begin */
21     private native void init();
22     static
23     {
24         Log.d(TAG, "load libuninstalled_moniter");
25         System.loadLibrary("uninstalled_moniter");
26     }
27     
28     @Override
29     public void onCreate(Bundle savedInstanceState)
30     {
31         super.onCreate(savedInstanceState);
32         Log.d(TAG, "onCreate");
33         
34         setContentView(R.layout.uninstalled_moniter_layout);
35         
36         init();
37     }
38     /* 函数段end */
39 }

核心——native方法头文件:

 1 /* 头文件begin */
 2 #include <jni.h>
 3 #include <stdio.h>
 4 #include <string.h>
 5 #include <android/log.h>
 6 #include <unistd.h>
 7 /* 头文件end */
 8 
 9 /* 宏定义begin */
10 //清0宏
11 #define MEM_ZERO(pDest, destSize) memset(pDest, 0, destSize)
12 
13 //LOG宏定义
14 #define LOG_INFO(tag, msg) __android_log_write(ANDROID_LOG_INFO, tag, msg)
15 #define LOG_DEBUG(tag, msg) __android_log_write(ANDROID_LOG_DEBUG, tag, msg)
16 #define LOG_WARN(tag, msg) __android_log_write(ANDROID_LOG_WARN, tag, msg)
17 #define LOG_ERROR(tag, msg) __android_log_write(ANDROID_LOG_ERROR, tag, msg)
18 /* 宏定义end */
19 
20 #ifndef _Included_main_activity_UninstalledMoniterActivity
21 #define _Included_main_activity_UninstalledMoniterActivity
22 #ifdef __cplusplus
23 extern "C" {
24 #endif
25 
26 #undef main_activity_UninstalledMoniterActivity_MODE_PRIVATE
27 #define main_activity_UninstalledMoniterActivity_MODE_PRIVATE 0L
28 #undef main_activity_UninstalledMoniterActivity_MODE_WORLD_READABLE
29 #define main_activity_UninstalledMoniterActivity_MODE_WORLD_READABLE 1L
30 #undef main_activity_UninstalledMoniterActivity_MODE_WORLD_WRITEABLE
31 #define main_activity_UninstalledMoniterActivity_MODE_WORLD_WRITEABLE 2L
32 #undef main_activity_UninstalledMoniterActivity_MODE_APPEND
33 #define main_activity_UninstalledMoniterActivity_MODE_APPEND 32768L
34 #undef main_activity_UninstalledMoniterActivity_MODE_MULTI_PROCESS
35 #define main_activity_UninstalledMoniterActivity_MODE_MULTI_PROCESS 4L
36 #undef main_activity_UninstalledMoniterActivity_BIND_AUTO_CREATE
37 #define main_activity_UninstalledMoniterActivity_BIND_AUTO_CREATE 1L
38 #undef main_activity_UninstalledMoniterActivity_BIND_DEBUG_UNBIND
39 #define main_activity_UninstalledMoniterActivity_BIND_DEBUG_UNBIND 2L
40 #undef main_activity_UninstalledMoniterActivity_BIND_NOT_FOREGROUND
41 #define main_activity_UninstalledMoniterActivity_BIND_NOT_FOREGROUND 4L
42 #undef main_activity_UninstalledMoniterActivity_BIND_ABOVE_CLIENT
43 #define main_activity_UninstalledMoniterActivity_BIND_ABOVE_CLIENT 8L
44 #undef main_activity_UninstalledMoniterActivity_BIND_ALLOW_OOM_MANAGEMENT
45 #define main_activity_UninstalledMoniterActivity_BIND_ALLOW_OOM_MANAGEMENT 16L
46 #undef main_activity_UninstalledMoniterActivity_BIND_WAIVE_PRIORITY
47 #define main_activity_UninstalledMoniterActivity_BIND_WAIVE_PRIORITY 32L
48 #undef main_activity_UninstalledMoniterActivity_BIND_IMPORTANT
49 #define main_activity_UninstalledMoniterActivity_BIND_IMPORTANT 64L
50 #undef main_activity_UninstalledMoniterActivity_BIND_ADJUST_WITH_ACTIVITY
51 #define main_activity_UninstalledMoniterActivity_BIND_ADJUST_WITH_ACTIVITY 128L
52 #undef main_activity_UninstalledMoniterActivity_CONTEXT_INCLUDE_CODE
53 #define main_activity_UninstalledMoniterActivity_CONTEXT_INCLUDE_CODE 1L
54 #undef main_activity_UninstalledMoniterActivity_CONTEXT_IGNORE_SECURITY
55 #define main_activity_UninstalledMoniterActivity_CONTEXT_IGNORE_SECURITY 2L
56 #undef main_activity_UninstalledMoniterActivity_CONTEXT_RESTRICTED
57 #define main_activity_UninstalledMoniterActivity_CONTEXT_RESTRICTED 4L
58 #undef main_activity_UninstalledMoniterActivity_RESULT_CANCELED
59 #define main_activity_UninstalledMoniterActivity_RESULT_CANCELED 0L
60 #undef main_activity_UninstalledMoniterActivity_RESULT_OK
61 #define main_activity_UninstalledMoniterActivity_RESULT_OK -1L
62 #undef main_activity_UninstalledMoniterActivity_RESULT_FIRST_USER
63 #define main_activity_UninstalledMoniterActivity_RESULT_FIRST_USER 1L
64 #undef main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_DISABLE
65 #define main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_DISABLE 0L
66 #undef main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_DIALER
67 #define main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_DIALER 1L
68 #undef main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SHORTCUT
69 #define main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SHORTCUT 2L
70 #undef main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SEARCH_LOCAL
71 #define main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SEARCH_LOCAL 3L
72 #undef main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SEARCH_GLOBAL
73 #define main_activity_UninstalledMoniterActivity_DEFAULT_KEYS_SEARCH_GLOBAL 4L
74 
75 /*
76  * Class:     main_activity_UninstalledMoniterActivity
77  * Method:    init
78  * Signature: ()V
79  */
80 JNIEXPORT void JNICALL Java_main_activity_UninstalledMoniterActivity_init(JNIEnv *, jobject);
81 
82 #ifdef __cplusplus
83 }
84 #endif
85 #endif

核心——native方法实现:

 1 /* 头文件begin */
 2 #include "main_activity_UninstalledMoniterActivity.h"
 3 /* 头文件end */
 4 
 5 #ifdef __cplusplus
 6 extern "C" {
 7 #endif
 8 
 9 /* 内全局变量begin */
10 static char c_TAG[] = "UninstalledMoniterActivity.init";
11 static jboolean b_IS_COPY = JNI_TRUE;
12 /* 内全局变量 */
13 
14 /*
15  * Class:     main_activity_UninstalledMoniterActivity
16  * Method:    init
17  * Signature: ()V
18  */
19 JNIEXPORT void JNICALL Java_main_activity_UninstalledMoniterActivity_init(JNIEnv *env, jobject obj)
20 {
21     jstring tag = (*env)->NewStringUTF(env, c_TAG);
22 
23     //初始化log
24     LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
25             , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "init OK"), &b_IS_COPY));
26 
27     //fork子进程,以执行轮询任务
28     pid_t pid = fork();
29     if (pid < 0)
30     {
31         //出错log
32         LOG_ERROR((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
33                 , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "fork error !!!"), &b_IS_COPY));
34     }
35     else if (pid == 0)
36     {
37         //子进程轮询"/data/data/pym.test.uninstalledmoniter"目录是否存在,若不存在则说明已被卸载
38         while (1)
39         {
40             FILE *p_file = fopen("/data/data/pym.test.uninstalledmoniter", "r");
41             if (p_file != NULL)
42             {
43                 fclose(p_file);
44 
45                 //目录存在log
46                 LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
47                             , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "I'm OK !!!"), &b_IS_COPY));
48 
49                 sleep(1);
50             }
51             else
52             {
53                 //目录不存在log
54                 LOG_DEBUG((*env)->GetStringUTFChars(env, tag, &b_IS_COPY)
55                             , (*env)->GetStringUTFChars(env, (*env)->NewStringUTF(env, "I'm NOT OK !!!"), &b_IS_COPY));
56 
57                 //执行命令am start -a android.intent.action.VIEW -d http://shouji.360.cn/web/uninstall/uninstall.html
58                 execlp("am", "am", "start", "-a", "android.intent.action.VIEW", "-d", "http://shouji.360.cn/web/uninstall/uninstall.html", (char *)NULL);
59             }
60         }
61     }
62     else
63     {
64         //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
65     }
66 }
67 
68 #ifdef __cplusplus
69 }
70 #endif

注1:为了调试方便,包含<android/log.h>,使得so在执行过程中也可以像Java端一样方便得打出log。相应的mk文件需要加上以下两句声明

LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
LOCAL_LDLIBS += -L$(SYSROOT)/usr/lib -llog

注2:代码中引用了360手机卫士的反馈地址,仅供大家学习、测试使用~~~

posted @ 2013-06-26 19:07 热气球 阅读(...) 评论(...) 编辑 收藏