Android學習之Service命令的妙用

Android系統不光在host上為我們提供了一些好用的命令, 同時device也有一些隱藏著的命令, 通常它是被系統調用,但是由於使用權限設定的原因, 普通的進程也能通過命令列去使用它們.
比如,我之前提到的<Android效能測試工具之dumpsys>http://www.bkjia.com/kf/201203/125340.html 及<Android調試工具之adbs>http://www.bkjia.com/kf/201203/125341.html 

在device中, 有一個service命令, 可以看到當前所有的service, 同時也可以使用它來往一些activity發送一些資訊
如下所示,  service的用法
[plain]
root@android:/ # service                                                        
Usage: service [-h|-?] 
       service list 
       service check SERVICE 
       service call SERVICE CODE [i32 INT | s16 STR] ... 
Options: 
   i32: Write the integer INT into the send parcel. 
   s16: Write the UTF-16 string STR into the send parcel. 
當前啟動並執行service
[plain]
root@android:/ # service list                                                   
Found 61 services: 
0   sip: [android.net.sip.ISipService] 
1   phone: [com.android.internal.telephony.ITelephony] 
2   iphonesubinfo: [com.android.internal.telephony.IPhoneSubInfo] 
3   simphonebook: [com.android.internal.telephony.IIccPhoneBook] 
4   isms: [com.android.internal.telephony.ISms] 
5   nfc: [android.nfc.INfcAdapter] 
6   samplingprofiler: [] 
7   diskstats: [] 
8   appwidget: [com.android.internal.appwidget.IAppWidgetService] 
9   backup: [android.app.backup.IBackupManager] 
10  uimode: [android.app.IUiModeManager] 
11  usb: [android.hardware.usb.IUsbManager] 
12  audio: [android.media.IAudioService] 
13  wallpaper: [android.app.IWallpaperManager] 
14  dropbox: [com.android.internal.os.IDropBoxManagerService] 
15  search: [android.app.ISearchManager] 
16  country_detector: [android.location.ICountryDetector] 
17  location: [android.location.ILocationManager] 
18  devicestoragemonitor: [] 
19  notification: [android.app.INotificationManager] 
20  mount: [IMountService] 
21  throttle: [android.net.IThrottleManager] 
22  connectivity: [android.net.IConnectivityManager] 
...... 

使用service的phone來打電話
[plain]
root@android:/ # service call phone <span style="color:#FF0000;">2</span> s16 "123"                                 
Result: Parcel(00000000    '....') 
此時, 就直接撥號了:), 但是這裡注意, 緊急號碼在這裡是不work的.

下面再來一個用來發簡訊的
[plain]
root@android:/ # service call isms <span style="color:#FF0000;">4</span> s16 "12345678" s16 "" s16 "hello world!" s16 "" s16 "" 

下面就說一下原理
大家先找到代碼frameworks/base/telephony/java/com/android/internal/telephony/ITelephony.aidl和ISms.aidl,
這兩個檔案都是給OEM廠商整合用的, 代碼我這裡就不貼了,細心的童鞋一眼就能看出來, 上面的"2", "4"就是指定了是哪一個函數
比如, 2 就是
[plain]
/** 
     * Place a call to the specified number. 
     * @param number the number to be called. 
     */ 
    void call(String number); 
4就是
[plain]
/** 
    * Send an SMS. 
    * 
    * @param smsc the SMSC to send the message through, or NULL for the 
    *  default SMSC 
    * @param text the body of the message to send 
    * @param sentIntent if not NULL this <code>PendingIntent</code> is 
    *  broadcast when the message is sucessfully sent, or failed. 
    *  The result code will be <code>Activity.RESULT_OK<code> for success, 
    *  or one of these errors:<br> 
    *  <code>RESULT_ERROR_GENERIC_FAILURE</code><br> 
    *  <code>RESULT_ERROR_RADIO_OFF</code><br> 
    *  <code>RESULT_ERROR_NULL_PDU</code><br> 
    *  For <code>RESULT_ERROR_GENERIC_FAILURE</code> the sentIntent may include 
    *  the extra "errorCode" containing a radio technology specific value, 
    *  generally only useful for troubleshooting.<br> 
    *  The per-application based SMS control checks sentIntent. If sentIntent 
    *  is NULL the caller will be checked against all unknown applications, 
    *  which cause smaller number of SMS to be sent in checking period. 
    * @param deliveryIntent if not NULL this <code>PendingIntent</code> is 
    *  broadcast when the message is delivered to the recipient.  The 
    *  raw pdu of the status report is in the extended data ("pdu"). 
    */ 
   void sendText(in String destAddr, in String scAddr, in String text, 
           in PendingIntent sentIntent, in PendingIntent deliveryIntent); 

所以, 以後要想在後台發簡訊,打電話,可以直接調用Java的Runtime Exec來調用service提供的命令, 這樣就可以部分繞過framework中的一些java service, 而直接跟更底層的c++/C實現的service直接互動:) 

摘自  Melody_lu123