SharedPreferences未得到清除android

Question

我在我的应用程序中有登录功能。这里当用户第一次登录时，用户的详细信息被保存在一个共享的首选项文件中。当用户下次登录时，用户直接进入第二个屏幕。这工作正常。现在我已经实现了注销功能。在这里，我明确了喜好。然后，如果我从另一个帐户登录，我仍然可以获得第一个帐户的用户详细信息。

这里是我的代码： -

public class SessionManagement 
{ 
    SharedPreferences pref; 

     // Editor for Shared preferences 
     SharedPreferences.Editor editor; 

     // ContextS 
     Context _context; 

     // Shared pref mode 
     int PRIVATE_MODE = 0; 

     // Sharedpref file name 
     private static final String PREF_NAME = "UserDetails"; 

     // All Shared Preferences Keys 
     private static final String IS_LOGIN = "IsLoggedIn"; 

     // User name (make variable public to access from outside) 
     public static final String KEY_EMAILID = "email"; 

     // Email address (make variable public to access from outside) 
     public static final String KEY_DEVICEURL = "deviceurl"; 

     public static final String KEY_ENDPOINTHOST = "endpointhost"; 
     public static final String KEY_DEVICENAME = "devicename"; 
     public static final String KEY_USERSNAME = "usersname"; 
     public static final String KEY_ENCODEDACCOUNTNAME = "encodedaccountname"; 
     public static final String KEY_HOSTURL = "hosturl"; 
     public static final String KEY_DEVICEiD = "deviceid"; 

     public static final String KEY_DEVICEREGISTERED = "deviceregistered"; 
     // Constructor 
     static SessionManagement session = null; 

    public static SessionManagement getInstance(Context context) 
    { 
    _context = context; 
    if(session == null) 
     session = new SessionManagement(); 
    return session; 
    } 
    public SessionManagement() 
    { 

     pref = _context.getSharedPreferences(PREF_NAME, PRIVATE_MODE); 
     editor = pref.edit(); 
    } 

     public void createLoginSession(String emailId, String deviceauthurl, String deviceid, String endpointhost, String devicename, String usersname, String encodedaccountname, String hosturl) 
     { 
      // Storing login value as TRUE 
      editor.putBoolean(IS_LOGIN, true); 

      editor.putBoolean(KEY_DEVICEREGISTERED, true); 
      editor.putString(KEY_EMAILID, emailId); 
      editor.putString(KEY_DEVICEURL, deviceurl); 
      editor.putString(KEY_DEVICEiD, deviceid); 
      editor.putString(KEY_ENDPOINTHOST, endpointhost); 
      editor.putString(KEY_DEVICENAME,devicename); 
      editor.putString(KEY_USERSNAME, usersname); 
      editor.putString(KEY_ENCODEDACCOUNTNAME, encodedaccountname); 
      editor.putString(KEY_HOSTURL, hosturl); 

      // commit changes 
      editor.commit(); 
     } 

     /** 
     * Get stored session data 
     * */ 
     public HashMap<String, String> getUserDetails() 
     { 
      HashMap<String, String> user = new HashMap<String, String>(); 

      user.put(KEY_EMAILID, pref.getString(KEY_EMAILID, null)); 
      user.put(KEY_DEVICEAUTHURL, pref.getString(KEY_DEVICEAUTHURL, null)); 
      user.put(KEY_DEVICEiD, pref.getString(KEY_DEVICEiD, null)); 
      user.put(KEY_ENDPOINTHOST, pref.getString(KEY_ENDPOINTHOST, null)); 
      user.put(KEY_DEVICENAME, pref.getString(KEY_DEVICENAME, null)); 
      user.put(KEY_USERSNAME, pref.getString(KEY_USERSNAME, null)); 
      user.put(KEY_ENCODEDACCOUNTNAME, pref.getString(KEY_ENCODEDACCOUNTNAME, null)); 
      user.put(KEY_HOSTURL, pref.getString(KEY_HOSTURL, null)); 

      // return user 
      return user; 

     } 
     /** 
     * Check login method wil check user login status 
     * If false it will redirect user to login page 
     * Else won't do anything 
     * */ 
     public void checkLogin() 
     { 
      // Check login status 
      if(!this.isLoggedIn()) 
      { 
       // user is not logged in redirect him to Login Activity 
       Intent i = new Intent(_context, Login.class); 
       // Closing all the Activities 
       i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 

       i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK); 

       // Add new Flag to start new Activity 
       i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 

       // Staring Login Activity 
        _context.startActivity(i); 
      } 

     } 

     // This function clears all session data and redirect the user to LoginActivity 
     /** 
      * Clear session details 
      * */ 
      public void logoutUser() 
      { 
       // Clearing all data from Shared Preferences 
       //editor.clear(); 
       editor.remove(KEY_DEVICEURL); 
       editor.remove(KEY_DEVICENAME); 
       editor.remove(KEY_DEVICEREGISTERED); 
       editor.remove(KEY_DEVICEiD); 
       editor.remove(KEY_EMAILID); 
       editor.remove(KEY_ENCODEDACCOUNTNAME); 
       editor.remove(KEY_ENDPOINTHOST); 
       editor.remove(KEY_HOSTURL); 
       editor.remove(KEY_USERSNAME); 
       editor.remove(IS_LOGIN); 
       editor.remove(PREF_NAME); 
       editor.clear(); 
       editor.commit(); 


       File file = new File("/data/data/com.zcv.acb/shared_prefs/UserDetails.xml"); 
       file.delete(); 


       // After logout redirect user to Loing Activity 
       Intent i = new Intent(_context, Login.class); 
       // Closing all the Activities 
       i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 

       i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK); 

       // Add new Flag to start new Activity 
       i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 

       // Staring Login Activity 
       _context.startActivity(i); 

      } 

      public boolean isLoggedIn() 
      { 
       return pref.getBoolean(IS_LOGIN, false); 
      } 
} 

Login.java

SessionManagement sessionManager =SessionManagement.getInstance(this); 
     session.logoutUser(); 
sessionManager.createLoginSession(username, deviceUrl, deviceId, endPointHost, deviceName, name, encodedAccountNameToken, hostUrlToken); 
    if(sessionManager.isLoggedIn()) 
     { 
      //Go directly to main activity 
     HashMap<String, String> userDetails = sessionManager.getUserDetails(); 

     startMyActivity(); 
     finish(); 
     } 

Logout.java

SessionManagement session =SessionManagement.getInstance(this); 
     session.logoutUser(); 
      this.finish(); 

有什么建议？

Answer 1

brother use this method to remove the string shared preference: 

     public static void removeSharedPrefStringData(Context context, String key) 
     { 

      SharedPreferences appInstallInfoSharedPref = context.getSharedPreferences(Constant.SHARED_PREF_NAME, context.MODE_MULTI_PROCESS); 

      Editor appInstallInfoEditor = appInstallInfoSharedPref.edit(); 
      appInstallInfoEditor.remove(key); 
      appInstallInfoEditor.commit(); 

     } 

set and get preference methods are here: 

    public static void setSharedPrefStringData(Context context, String key, String value) 
    { 
     SharedPreferences appInstallInfoSharedPref = context.getSharedPreferences(Constant.SHARED_PREF_NAME, context.MODE_MULTI_PROCESS); 
     Editor appInstallInfoEditor = appInstallInfoSharedPref.edit(); 
     appInstallInfoEditor.putString(key, value); 
     appInstallInfoEditor.commit(); 
    } 

    public static String getSharedPrefStringData(Context context, String key) 
    { 

     SharedPreferences userAcountPreference = context.getSharedPreferences(Constant.SHARED_PREF_NAME, Context.MODE_MULTI_PROCESS); 

     return userAcountPreference.getString(key, ""); 

    } 

Answer 2

用于保存共享偏好

当节省共享偏好调用此方法savePreference("Username","some name");

时删除共享偏好调用此方法savePreference("Username","");

private void savePreferences(String key, String value) 
{ 
    SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this); 
    Editor editor = sharedPreferences.edit(); 
    editor.putString(key, value); 
    editor.commit(); 
} 

为得到共享偏好

现在每当检查首选项时，你会得到空字符串重定向用户登录活动。其他用户屏幕

private boolean loadSavedPreferences() 
{ 
    boolean check=false; 
    SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this); 
    String name = sharedPreferences.getString("Username", ""); 
    if(!name.equals("")) 
    { 
     check = true; 
    } 
    return check; 
} 

这很简单。

更新：2

public void createLoginSession(String emailId, String deviceauthurl, String deviceid, String endpointhost, String devicename, String usersname, String encodedaccountname, String hosturl) 
    { 
     // Storing login value as TRUE 
     savePreferences(IS_LOGIN, true); 

     savePreferences(KEY_DEVICEREGISTERED, true); 
     savePreferences(KEY_EMAILID, emailId); 
     savePreferences(KEY_DEVICEURL, deviceurl); 
     savePreferences(KEY_DEVICEiD, deviceid); 
     savePreferences(KEY_ENDPOINTHOST, endpointhost); 
     savePreferences(KEY_DEVICENAME,devicename); 
     savePreferences(KEY_USERSNAME, usersname); 
     savePreferences(KEY_ENCODEDACCOUNTNAME, encodedaccountname); 
     savePreferences(KEY_HOSTURL, hosturl); 

    } 

保持一件事记在心里。 savePreference只接受（String，String）你需要为（String，boolean）创建一个

Answer 3

问题是，你使用的是2个不同的会话管理对象，即登录有不同的对象，注销会有不同的会话管理对象。这就是为什么它不工作。它们都属于不同的共享偏好对象。当你初始化注销对象时，会创建一个更多的共享首选项对象。解决方案是使用单例对象或使用静态方法和成员来解决你的问题。但是我想单身人士对此很有帮助。 chnage你这样的代码：

public class SessionManagement { 
static SessionManagement man = null; 

public static SessionManagement getInstance(){ 
if(man == null) 
    man = new SessionManagement(); 
return man; 
} 

... 

} 

，让你的类的构造函数私有（只是删除公众和你的构造与私人代替）在这之后的所有代码

保持不变。

现在登录活动和注销活动，通过调用这个

SessionManagement sess = SessionManagement.getInstance();