如何在Android中使用SharedPreferences来存储,获取和编辑值

时间:2010-09-02 06:26:53

标签: android sharedpreferences

我想存储一个时间值,需要检索和编辑它。如何使用SharedPreferences执行此操作?

31 个答案:

答案 0 :(得分:819)

要获取共享首选项,请使用以下方法 在您的活动中:

SharedPreferences prefs = this.getSharedPreferences(
      "com.example.app", Context.MODE_PRIVATE);

阅读偏好:

String dateTimeKey = "com.example.app.datetime";

// use a default value using new Date()
long l = prefs.getLong(dateTimeKey, new Date().getTime()); 

编辑和保存偏好

Date dt = getSomeDate();
prefs.edit().putLong(dateTimeKey, dt.getTime()).apply();

android sdk的示例目录包含检索和存储共享首选项的示例。它位于:

<android-sdk-home>/samples/android-<platformversion>/ApiDemos directory

修改==&GT;

我注意到,在commit()apply()之间写下区别也很重要。

commit() 如果成功保存成功,则返回true false。它将值保存到SharedPreferences 同步

2.3中添加了

apply() ,并且在成功或失败时都不会返回任何值。它会立即将值保存到SharedPreferences,但会启动异步提交。 更多细节是here

答案 1 :(得分:272)

将值存储在共享首选项中:

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Name","Harneet");
editor.apply();

从共享首选项中检索值:

SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
String name = preferences.getString("Name", "");
if(!name.equalsIgnoreCase(""))
{
    name = name + "  Sethi";  /* Edit the value here*/
}

答案 2 :(得分:162)

sharedpreference

编辑数据
 SharedPreferences.Editor editor = getPreferences(MODE_PRIVATE).edit();
 editor.putString("text", mSaved.getText().toString());
 editor.putInt("selection-start", mSaved.getSelectionStart());
 editor.putInt("selection-end", mSaved.getSelectionEnd());
 editor.apply();

sharedpreference

检索数据
SharedPreferences prefs = getPreferences(MODE_PRIVATE); 
String restoredText = prefs.getString("text", null);
if (restoredText != null) 
{
  //mSaved.setText(restoredText, TextView.BufferType.EDITABLE);
  int selectionStart = prefs.getInt("selection-start", -1);
  int selectionEnd = prefs.getInt("selection-end", -1);
  /*if (selectionStart != -1 && selectionEnd != -1)
  {
     mSaved.setSelection(selectionStart, selectionEnd);
  }*/
}

修改

我从API Demo示例中获取了此片段。那里有一个EditText框。在这个context中,它不是必需的。我正在评论相同的内容。

答案 3 :(得分:38)

写:

SharedPreferences preferences = getSharedPreferences("AUTHENTICATION_FILE_NAME", Context.MODE_WORLD_WRITEABLE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("Authentication_Id",userid.getText().toString());
editor.putString("Authentication_Password",password.getText().toString());
editor.putString("Authentication_Status","true");
editor.apply();

阅读:

SharedPreferences prfs = getSharedPreferences("AUTHENTICATION_FILE_NAME", Context.MODE_PRIVATE);
String Astatus = prfs.getString("Authentication_Status", "");

答案 4 :(得分:26)

最简单的方法:

保存:

getPreferences(MODE_PRIVATE).edit().putString("Name of variable",value).commit();

要检索:

your_variable = getPreferences(MODE_PRIVATE).getString("Name of variable",default value);

答案 5 :(得分:17)

在首选项中设置值:

// MY_PREFS_NAME - a static String variable like: 
//public static final String MY_PREFS_NAME = "MyPrefsFile";
SharedPreferences.Editor editor = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE).edit();
 editor.putString("name", "Elena");
 editor.putInt("idName", 12);
 editor.commit();

从首选项中检索数据:

SharedPreferences prefs = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE); 
String restoredText = prefs.getString("text", null);
if (restoredText != null) {
  String name = prefs.getString("name", "No name defined");//"No name defined" is the default value.
  int idName = prefs.getInt("idName", 0); //0 is the default value.
}

更多信息:

Using Shared Preferences

Shared Preferences

答案 6 :(得分:15)

存储信息

SharedPreferences preferences = getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("username", username.getText().toString());
editor.putString("password", password.getText().toString());
editor.putString("logged", "logged");
editor.commit();

重置首选项

SharedPreferences.Editor editor = preferences.edit();
editor.clear();
editor.commit();

答案 7 :(得分:12)

Singleton共享首选项类。它可能对将来的其他人有所帮助。

import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;

public class SharedPref
{
    private static SharedPreferences mSharedPref;
    public static final String NAME = "NAME";
    public static final String AGE = "AGE";
    public static final String IS_SELECT = "IS_SELECT";

    private SharedPref()
    {

    }

    public static void init(Context context)
    {
        if(mSharedPref == null)
            mSharedPref = context.getSharedPreferences(context.getPackageName(), Activity.MODE_PRIVATE);
    }

    public static String read(String key, String defValue) {
        return mSharedPref.getString(key, defValue);
    }

    public static void write(String key, String value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putString(key, value);
        prefsEditor.commit();
    }

    public static boolean read(String key, boolean defValue) {
        return mSharedPref.getBoolean(key, defValue);
    }

    public static void write(String key, boolean value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putBoolean(key, value);
        prefsEditor.commit();
    }

    public static Integer read(String key, int defValue) {
        return mSharedPref.getInt(key, defValue);
    }

    public static void write(String key, Integer value) {
        SharedPreferences.Editor prefsEditor = mSharedPref.edit();
        prefsEditor.putInt(key, value).commit();
    }
}

只需在SharedPref.init()上致电MainActivity一次

SharedPref.init(getApplicationContext());

写入数据

SharedPref.write(SharedPref.NAME, "XXXX");//save string in shared preference.
SharedPref.write(SharedPref.AGE, 25);//save int in shared preference.
SharedPref.write(SharedPref.IS_SELECT, true);//save boolean in shared preference.

读取数据

String name = SharedPref.read(SharedPref.NAME, null);//read string in shared preference.
int age = SharedPref.read(SharedPref.AGE, 0);//read int in shared preference.
boolean isSelect = SharedPref.read(SharedPref.IS_SELECT, false);//read boolean in shared preference.

答案 8 :(得分:12)

在任何应用程序中,都可以通过PreferenceManager实例及其相关方法getDefaultSharedPreferences(Context)访问默认首选项。

使用SharedPreference实例,可以使用 getInt(String key,int defVal)检索任何首选项的int值。我们对这种情况感兴趣的偏好是反制。

在我们的例子中,我们可以使用edit()修改SharedPreference实例并使用putInt(String key, int newVal)我们增加了应用程序的计数,该应用程序超出了应用程序并且相应地显示。< / p>

要进一步演示此功能,重新启动并重新启动应用程序,您会注意到每次重新启动应用程序时计数都会增加。

<强> PreferencesDemo.java

代码:

package org.example.preferences;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.widget.TextView;

public class PreferencesDemo extends Activity {
   /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // Get the app's shared preferences
        SharedPreferences app_preferences = 
        PreferenceManager.getDefaultSharedPreferences(this);

        // Get the value for the run counter
        int counter = app_preferences.getInt("counter", 0);

        // Update the TextView
        TextView text = (TextView) findViewById(R.id.text);
        text.setText("This app has been started " + counter + " times.");

        // Increment the counter
        SharedPreferences.Editor editor = app_preferences.edit();
        editor.putInt("counter", ++counter);
        editor.commit(); // Very important
    }
}

<强> main.xml中

<强>代码:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="vertical"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent" >

        <TextView
            android:id="@+id/text"  
            android:layout_width="fill_parent" 
            android:layout_height="wrap_content" 
            android:text="@string/hello" />
</LinearLayout>

答案 9 :(得分:12)

如果您正在与团队中的其他开发人员一起制作大型应用程序,并且打算在没有分散代码或不同SharedPreferences实例的情况下完成所有组织,那么您可以执行以下操作:

//SharedPreferences manager class
public class SharedPrefs {

    //SharedPreferences file name
    private static String SHARED_PREFS_FILE_NAME = "my_app_shared_prefs";

    //here you can centralize all your shared prefs keys
    public static String KEY_MY_SHARED_BOOLEAN = "my_shared_boolean";
    public static String KEY_MY_SHARED_FOO = "my_shared_foo";

    //get the SharedPreferences object instance
    //create SharedPreferences file if not present


    private static SharedPreferences getPrefs(Context context) {
        return context.getSharedPreferences(SHARED_PREFS_FILE_NAME, Context.MODE_PRIVATE);
    }

    //Save Booleans
    public static void savePref(Context context, String key, boolean value) {
        getPrefs(context).edit().putBoolean(key, value).commit();       
    }

    //Get Booleans
    public static boolean getBoolean(Context context, String key) {
        return getPrefs(context).getBoolean(key, false);
    }

    //Get Booleans if not found return a predefined default value
    public static boolean getBoolean(Context context, String key, boolean defaultValue) {
        return getPrefs(context).getBoolean(key, defaultValue);
    }

    //Strings
    public static void save(Context context, String key, String value) {
        getPrefs(context).edit().putString(key, value).commit();
    }

    public static String getString(Context context, String key) {
        return getPrefs(context).getString(key, "");
    }

    public static String getString(Context context, String key, String defaultValue) {
        return getPrefs(context).getString(key, defaultValue);
    }

    //Integers
    public static void save(Context context, String key, int value) {
        getPrefs(context).edit().putInt(key, value).commit();
    }

    public static int getInt(Context context, String key) {
        return getPrefs(context).getInt(key, 0);
    }

    public static int getInt(Context context, String key, int defaultValue) {
        return getPrefs(context).getInt(key, defaultValue);
    }

    //Floats
    public static void save(Context context, String key, float value) {
        getPrefs(context).edit().putFloat(key, value).commit();
    }

    public static float getFloat(Context context, String key) {
        return getPrefs(context).getFloat(key, 0);
    }

    public static float getFloat(Context context, String key, float defaultValue) {
        return getPrefs(context).getFloat(key, defaultValue);
    }

    //Longs
    public static void save(Context context, String key, long value) {
        getPrefs(context).edit().putLong(key, value).commit();
    }

    public static long getLong(Context context, String key) {
        return getPrefs(context).getLong(key, 0);
    }

    public static long getLong(Context context, String key, long defaultValue) {
        return getPrefs(context).getLong(key, defaultValue);
    }

    //StringSets
    public static void save(Context context, String key, Set<String> value) {
        getPrefs(context).edit().putStringSet(key, value).commit();
    }

    public static Set<String> getStringSet(Context context, String key) {
        return getPrefs(context).getStringSet(key, null);
    }

    public static Set<String> getStringSet(Context context, String key, Set<String> defaultValue) {
        return getPrefs(context).getStringSet(key, defaultValue);
    }
}

在您的活动中,您可以通过这种方式保存SharedPreferences

//saving a boolean into prefs
SharedPrefs.savePref(this, SharedPrefs.KEY_MY_SHARED_BOOLEAN, booleanVar);

您可以通过这种方式检索您的SharedPreferences

//getting a boolean from prefs
booleanVar = SharedPrefs.getBoolean(this, SharedPrefs.KEY_MY_SHARED_BOOLEAN);

答案 10 :(得分:8)

存储在SharedPreferences中

SharedPreferences preferences = getSharedPreferences("temp", getApplicationContext().MODE_PRIVATE);
Editor editor = preferences.edit();
editor.putString("name", name);
editor.commit();

获取SharedPreferences

SharedPreferences preferences=getSharedPreferences("temp", getApplicationContext().MODE_PRIVATE);
String name=preferences.getString("name",null);

注意:&#34; temp&#34;是共享名称和&#34;名称&#34;是输入值。如果值没有退出则返回null

答案 11 :(得分:8)

如何按SharedPreferences存储登录值的简单解决方案。

您可以扩展MainActivity课程或其他课程,您将在其中存储“您想要保留的内容的价值”。把它放到作家和读者类中:

public static final String GAME_PREFERENCES_LOGIN = "Login";

这里输入InputClassOutputClass分别是输出类。

// This is a storage, put this in a class which you can extend or in both classes:
//(input and output)
public static final String GAME_PREFERENCES_LOGIN = "Login";

// String from the text input (can be from anywhere)
String login = inputLogin.getText().toString();

// then to add a value in InputCalss "SAVE",
SharedPreferences example = getSharedPreferences(GAME_PREFERENCES_LOGIN, 0);
Editor editor = example.edit();
editor.putString("value", login);
editor.commit();

现在你可以在其他地方使用它,就像其他类一样。以下是OutputClass

SharedPreferences example = getSharedPreferences(GAME_PREFERENCES_LOGIN, 0);
String userString = example.getString("value", "defValue");

// the following will print it out in console
Logger.getLogger("Name of a OutputClass".class.getName()).log(Level.INFO, userString);

答案 12 :(得分:7)

修改

SharedPreferences pref = getSharedPreferences("YourPref", MODE_PRIVATE);
SharedPreferences.Editor editor = pref.edit();
editor.putString("yourValue", value);
editor.commit();

SharedPreferences pref = getSharedPreferences("YourPref", MODE_PRIVATE);
value= pref.getString("yourValue", "");

答案 13 :(得分:6)

您可以使用此方法保存价值:

<div style="background-image:url(<?php echo $imageUrl?>) no-repeat center center fixed">
</div>
<?php
$imageUrl = 'http://azcombats.com/bg.jpg';
?>

使用此方法,您可以从SharedPreferences获取价值:

public void savePreferencesForReasonCode(Context context,
    String key, String value) {
    SharedPreferences sharedPreferences = PreferenceManager
    .getDefaultSharedPreferences(context);
    SharedPreferences.Editor editor = sharedPreferences.edit();
    editor.putString(key, value);
    editor.commit();
    }

此处public String getPreferences(Context context, String prefKey) { SharedPreferences sharedPreferences = PreferenceManager .getDefaultSharedPreferences(context); return sharedPreferences.getString(prefKey, ""); } 是您用于保存特定值的键。感谢。

答案 14 :(得分:6)

editor.putString("text", mSaved.getText().toString());

此处,mSaved可以是我们可以提取字符串的任何TextViewEditText。你可以简单地指定一个字符串。此处的文字将是保存从mSavedTextViewEditText)获得的值的关键字。

SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);

此外,无需使用包名称保存首选项文件,即“com.example.app”。您可以提及自己的首选名称。希望这有帮助!

答案 15 :(得分:6)

SharedPreferences的基本思想是将内容存储在XML文件中。

  1. 声明您的xml文件路径。(如果您没有此文件,Android将创建它。如果您有此文件,Android将访问它。)

    SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);
    
  2. 将值写入共享首选项

    prefs.edit().putLong("preference_file_key", 1010101).apply();
    

    preference_file_key是共享首选项文件的名称。 1010101是您需要存储的值。

    apply()最后是保存更改。如果您从apply()收到错误,请将其更改为commit()。所以这个替代句子是

    prefs.edit().putLong("preference_file_key", 1010101).commit();
    
  3. 从共享首选项中读取

    SharedPreferences sp = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);
    long lsp = sp.getLong("preference_file_key", -1);
    
    如果lsp没有价值,

    -1将为preference_file_key。如果'preference_file_key'有值,则返回this的值。

  4. 完整的写作代码是

        SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);    // Declare xml file
        prefs.edit().putLong("preference_file_key", 1010101).apply();    // Write the value to key.
    

    阅读代码是

        SharedPreferences sf = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);    // Declare xml file
        long lsp = sp.getLong("preference_file_key", -1);    // Read the key and store in lsp
    

答案 16 :(得分:5)

人们建议如何使用 SharedPreferences 。我做了demo project here。样本的关键点是使用 ApplicationContext&amp;单个共享偏好对象。这演示了如何将 SharedPreferences 与以下功能结合使用: -

  • 使用singelton类访问/更新SharedPreferences
  • 无需为读/写SharedPreferences
  • 传递上下文
  • 它使用apply()而不是commit()
  • apply()是异步保存,不返回任何内容,它先在内存中更新值&amp;更改将在以后写入磁盘 asynchronusly。
  • commit()是同步保存,它根据结果返回true / false。更改将同步写入磁盘
  • 适用于android 2.3+版本

用法示例如下: -

MyAppPreference.getInstance().setSampleStringKey("some_value");
String value= MyAppPreference.getInstance().getSampleStringKey();

Get source code here &安培;可以在developer.android.com上找到详细的API here

答案 17 :(得分:5)

有史以来的最佳做法

创建以 PreferenceManager 命名的接口

// Interface to save values in shared preferences and also for retrieve values from shared preferences
public interface PreferenceManager {

    SharedPreferences getPreferences();
    Editor editPreferences();

    void setString(String key, String value);
    String getString(String key);

    void setBoolean(String key, boolean value);
    boolean getBoolean(String key);

    void setInteger(String key, int value);
    int getInteger(String key);

    void setFloat(String key, float value);
    float getFloat(String key);

}

如何使用活动 / 片段

public class HomeActivity extends AppCompatActivity implements PreferenceManager{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout_activity_home);
    }

    @Override
    public SharedPreferences getPreferences(){
        return getSharedPreferences("SP_TITLE", Context.MODE_PRIVATE);
    }

    @Override
    public SharedPreferences.Editor editPreferences(){
        return getPreferences().edit();
    }

    @Override
    public void setString(String key, String value) {
        editPreferences().putString(key, value).commit();
    }

    @Override
    public String getString(String key) {
        return getPreferences().getString(key, "");
    }

    @Override
    public void setBoolean(String key, boolean value) {
        editPreferences().putBoolean(key, value).commit();
    }

    @Override
    public boolean getBoolean(String key) {
        return  getPreferences().getBoolean(key, false);
    }

    @Override
    public void setInteger(String key, int value) {
        editPreferences().putInt(key, value).commit();
    }

    @Override
    public int getInteger(String key) {
        return getPreferences().getInt(key, 0);
    }

    @Override
    public void setFloat(String key, float value) {
        editPreferences().putFloat(key, value).commit();
    }

    @Override
    public float getFloat(String key) {
        return getPreferences().getFloat(key, 0);
    }
}

注意:使用 SP_TITLE 替换您的SharedPreference键。

<强>示例:

将字符串存储在 shareperence

setString("my_key", "my_value");
来自 shareperence

获取字符串

String strValue = getString("my_key");

希望这会对你有所帮助。

答案 18 :(得分:5)

将值存储在共享首选项中:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sp.edit();
editor.putString("Name","Jayesh");
editor.commit();

从共享首选项中检索值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
String name = sp.getString("Name", ""); // Second parameter is the default value.

答案 19 :(得分:4)

保存

PreferenceManager.getDefaultSharedPreferences(this).edit().putString("VarName","your value").apply();

要撤退:

String name = PreferenceManager.getDefaultSharedPreferences(this).getString("VarName","defaultValue");
  

默认值为:如果此首选项不存在,则返回值。

     

您可以使用 getActivity() getApplicationContext更改“ ” ) in   一些案例

答案 20 :(得分:3)

使用此示例简单明了并检查

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.example.sairamkrishna.myapplication" >

   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:theme="@style/AppTheme" >

      <activity
         android:name=".MainActivity"
         android:label="@string/app_name" >

         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>

      </activity>

   </application>
</manifest>
public class MainActivity extends AppCompatActivity {
   EditText ed1,ed2,ed3;
   Button b1;

   public static final String MyPREFERENCES = "MyPrefs" ;
   public static final String Name = "nameKey";
   public static final String Phone = "phoneKey";
   public static final String Email = "emailKey";

   SharedPreferences sharedpreferences;

   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);

      ed1=(EditText)findViewById(R.id.editText);
      ed2=(EditText)findViewById(R.id.editText2);
      ed3=(EditText)findViewById(R.id.editText3);

      b1=(Button)findViewById(R.id.button);
      sharedpreferences = getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);

      b1.setOnClickListener(new View.OnClickListener() {
         @Override
         public void onClick(View v) {
            String n  = ed1.getText().toString();
            String ph  = ed2.getText().toString();
            String e  = ed3.getText().toString();

            SharedPreferences.Editor editor = sharedpreferences.edit();

            editor.putString(Name, n);
            editor.putString(Phone, ph);
            editor.putString(Email, e);
            editor.commit();
            Toast.makeText(MainActivity.this,"Thanks",Toast.LENGTH_LONG).show();
         }
      });
   }

}

答案 21 :(得分:2)

我想在此处添加,在使用SharedPreferences时,此问题的大多数代码段都会有类似MODE_PRIVATE的内容。好吧,MODE_PRIVATE意味着您写入此共享首选项的任何内容只能由您的应用程序读取。

无论你传递给getSharedPreferences()方法的密钥是什么,android都会创建一个具有该名称的文件并将偏好数据存储到其中。 还要记住,当您打算为应用程序提供多个首选项文件时,应该使用getSharedPreferences()。如果您打算使用单个首选项文件并将所有键值对存储到其中,则使用getSharedPreference()方法。很奇怪为什么每个人(包括我自己)都只使用getSharedPreferences()风格而不理解上述两者之间的区别。

以下视频教程应该有所帮助 https://www.youtube.com/watch?v=2PcAQ1NBy98

答案 22 :(得分:2)

使用此simple library,以下是调用SharedPreferences的方法..

TinyDB tinydb = new TinyDB(context);

tinydb.putInt("clickCount", 2);

tinydb.putString("userName", "john");
tinydb.putBoolean("isUserMale", true); 

tinydb.putList("MyUsers", mUsersArray);
tinydb.putImagePNG("DropBox/WorkImages", "MeAtlunch.png", lunchBitmap);

//These plus the corresponding get methods are all Included

答案 23 :(得分:2)

简单无忧::“Android-SharedPreferences-Helper”库

迟到总比没有好:我创建了the "Android-SharedPreferences-Helper" library来帮助降低使用SharedPreferences的复杂性和工作量。它还提供了一些扩展功能。它提供的几件事情如下:

  
      
  • 一行初始化和设置
  •   
  • 轻松选择是使用默认首选项还是自定义首选项文件
  •   
  • 预定义(数据类型默认值)和可自定义(您可以选择的)每种数据类型的默认值
  •   
  • 只需使用额外的参数
  • 即可为单次使用设置不同的默认值   
  • 您可以像默认类一样注册和取消注册OnSharedPreferenceChangeListener
  •   
dependencies {
    ...
    ...
    compile(group: 'com.viralypatel.sharedpreferenceshelper', name: 'library', version: '1.1.0', ext: 'aar')
}
  

SharedPreferencesHelper对象的声明:(在课堂上推荐   电平)

SharedPreferencesHelper sph; 
  

SharedPreferencesHelper对象的实例化:(推荐于   onCreate()方法)

// use one of the following ways to instantiate
sph = new SharedPreferencesHelper(this); //this will use default shared preferences
sph = new SharedPreferencesHelper(this, "myappprefs"); // this will create a named shared preference file
sph = new SharedPreferencesHelper(this, "myappprefs", 0); // this will allow you to specify a mode
  

将值放入共享首选项

相当简单!与默认方式(使用SharedPreferences类时)不同,您不需要随时调用.edit().commit()

sph.putBoolean("boolKey", true);
sph.putInt("intKey", 123);
sph.putString("stringKey", "string value");
sph.putLong("longKey", 456876451);
sph.putFloat("floatKey", 1.51f);

// putStringSet is supported only for android versions above HONEYCOMB
Set name = new HashSet();
name.add("Viral");
name.add("Patel");
sph.putStringSet("name", name);

就是这样!您的值存储在共享首选项中。

  

从共享偏好中获取值

再一次,只用一个简单的方法调用键名。

sph.getBoolean("boolKey");
sph.getInt("intKey");
sph.getString("stringKey");
sph.getLong("longKey");
sph.getFloat("floatKey");

// getStringSet is supported only for android versions above HONEYCOMB
sph.getStringSet("name");
  

它有很多其他扩展功能

GitHub Repository Page上查看扩展功能,使用和安装说明等的详细信息。

答案 24 :(得分:2)

我为sharedpreferences写了一个帮助类:

import android.content.Context;
import android.content.SharedPreferences;

/**
 * Created by mete_ on 23.12.2016.
 */
public class HelperSharedPref {

Context mContext;

public HelperSharedPref(Context mContext) {
    this.mContext = mContext;
}

/**
 *
 * @param key Constant RC
 * @param value Only String, Integer, Long, Float, Boolean types
 */
public void saveToSharedPref(String key, Object value) throws Exception {
    SharedPreferences.Editor editor = mContext.getSharedPreferences(key, Context.MODE_PRIVATE).edit();
    if (value instanceof String) {
        editor.putString(key, (String) value);
    } else if (value instanceof Integer) {
        editor.putInt(key, (Integer) value);
    } else if (value instanceof Long) {
        editor.putLong(key, (Long) value);
    } else if (value instanceof Float) {
        editor.putFloat(key, (Float) value);
    } else if (value instanceof Boolean) {
        editor.putBoolean(key, (Boolean) value);
    } else {
        throw new Exception("Unacceptable object type");
    }

    editor.commit();
}

/**
 * Return String
 * @param key
 * @return null default is null
 */
public String loadStringFromSharedPref(String key) throws Exception {
    SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
    String restoredText = prefs.getString(key, null);

    return restoredText;
}

/**
 * Return int
 * @param key
 * @return null default is -1
 */
public Integer loadIntegerFromSharedPref(String key) throws Exception {
    SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
    Integer restoredText = prefs.getInt(key, -1);

    return restoredText;
}

/**
 * Return float
 * @param key
 * @return null default is -1
 */
public Float loadFloatFromSharedPref(String key) throws Exception {
    SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
    Float restoredText = prefs.getFloat(key, -1);

    return restoredText;
}

/**
 * Return long
 * @param key
 * @return null default is -1
 */
public Long loadLongFromSharedPref(String key) throws Exception {
    SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
    Long restoredText = prefs.getLong(key, -1);

    return restoredText;
}

/**
 * Return boolean
 * @param key
 * @return null default is false
 */
public Boolean loadBooleanFromSharedPref(String key) throws Exception {
    SharedPreferences prefs = mContext.getSharedPreferences(key, Context.MODE_PRIVATE);
    Boolean restoredText = prefs.getBoolean(key, false);

    return restoredText;
}

}

答案 25 :(得分:2)

SharedPreferences.Editor editor = getSharedPreferences("identifier", 
MODE_PRIVATE).edit();
//identifier is the unique to fetch data from your SharedPreference.


editor.putInt("keyword", 0); 
// saved value place with 0.
//use this "keyword" to fetch saved value again.
editor.commit();//important line without this line your value is not stored in preference   

// fetch the stored data using ....

SharedPreferences prefs = getSharedPreferences("identifier", MODE_PRIVATE); 
// here both identifier will same

int fetchvalue = prefs.getInt("keyword", 0);
// here keyword will same as used above.
// 0 is default value when you nothing save in preference that time fetch value is 0.

您需要在AdapterClass中使用SharedPreferences或任何其他。 那个时候只是使用这个声明并使用上面的相同屁股。

SharedPreferences.Editor editor = context.getSharedPreferences("idetifier", 
Context.MODE_PRIVATE).edit();
SharedPreferences prefs = context.getSharedPreferences("identifier", Context.MODE_PRIVATE);

//here context is your application context

表示字符串或布尔值

editor.putString("stringkeyword", "your string"); 
editor.putBoolean("booleankeyword","your boolean value");
editor.commit();

获取与上述相同的数据

String fetchvalue = prefs.getString("keyword", "");
Boolean fetchvalue = prefs.getBoolean("keyword", "");

答案 26 :(得分:1)

2.forstoring in shared prefrence

SharedPreferences.Editor editor = 
getSharedPreferences("DeviceToken",MODE_PRIVATE).edit();
                    editor.putString("DeviceTokenkey","ABABABABABABABB12345");
editor.apply();

2.检索相同用途

    SharedPreferences prefs = getSharedPreferences("DeviceToken", 
 MODE_PRIVATE);
  String deviceToken = prefs.getString("DeviceTokenkey", null);

答案 27 :(得分:1)

将值存储在共享首选项中:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor editor = sp.edit();
editor.putString("Name","Jayesh");
editor.commit();

从共享首选项中检索值:

SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(this);
String name = sp.getString("Name", "");

答案 28 :(得分:1)

我创建了一个助手课程,让我的生活变得轻松。这是一个通用类,并且有许多常用于共享首选项,电子邮件有效期,日期时间格式等应用程序的方法。在您的代码中复制此类,并在您需要的任何地方访问它。

 import android.app.AlertDialog;
 import android.app.ProgressDialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.SharedPreferences;
 import android.support.v4.app.FragmentActivity;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.EditText;
 import android.widget.Toast;

 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Random;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.regex.PatternSyntaxException;

/**
* Created by Zohaib Hassan on 3/4/2016.
*/
 public class Helper {

private static ProgressDialog pd;

public static void saveData(String key, String value, Context context) {
    SharedPreferences sp = context.getApplicationContext()
            .getSharedPreferences("appData", 0);
    SharedPreferences.Editor editor;
    editor = sp.edit();
    editor.putString(key, value);
    editor.commit();
}

public static void deleteData(String key, Context context){
    SharedPreferences sp = context.getApplicationContext()
            .getSharedPreferences("appData", 0);
    SharedPreferences.Editor editor;
    editor = sp.edit();
    editor.remove(key);
    editor.commit();

}

public static String getSaveData(String key, Context context) {
    SharedPreferences sp = context.getApplicationContext()
            .getSharedPreferences("appData", 0);
    String data = sp.getString(key, "");
    return data;

}




public static long dateToUnix(String dt, String format) {
    SimpleDateFormat formatter;
    Date date = null;
    long unixtime;
    formatter = new SimpleDateFormat(format);
    try {
        date = formatter.parse(dt);
    } catch (Exception ex) {

        ex.printStackTrace();
    }
    unixtime = date.getTime();
    return unixtime;

}

public static String getData(long unixTime, String formate) {

    long unixSeconds = unixTime;
    Date date = new Date(unixSeconds);
    SimpleDateFormat sdf = new SimpleDateFormat(formate);
    String formattedDate = sdf.format(date);
    return formattedDate;
}

public static String getFormattedDate(String date, String currentFormat,
                                      String desiredFormat) {
    return getData(dateToUnix(date, currentFormat), desiredFormat);
}




public static double distance(double lat1, double lon1, double lat2,
                              double lon2, char unit) {
    double theta = lon1 - lon2;
    double dist = Math.sin(deg2rad(lat1)) * Math.sin(deg2rad(lat2))
            + Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2))
            * Math.cos(deg2rad(theta));
    dist = Math.acos(dist);
    dist = rad2deg(dist);
    dist = dist * 60 * 1.1515;
    if (unit == 'K') {
        dist = dist * 1.609344;
    } else if (unit == 'N') {
        dist = dist * 0.8684;
    }
    return (dist);
}

/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
/* :: This function converts decimal degrees to radians : */
/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
private static double deg2rad(double deg) {
    return (deg * Math.PI / 180.0);
}

/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
/* :: This function converts radians to decimal degrees : */
/* ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: */
private static double rad2deg(double rad) {
    return (rad * 180.0 / Math.PI);
}

public static int getRendNumber() {
    Random r = new Random();
    return r.nextInt(360);
}

public static void hideKeyboard(Context context, EditText editText) {
    InputMethodManager imm = (InputMethodManager) context
            .getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);
}

public static void showLoder(Context context, String message) {
    pd = new ProgressDialog(context);

    pd.setCancelable(false);
    pd.setMessage(message);
    pd.show();
}

public static void showLoderImage(Context context, String message) {
    pd = new ProgressDialog(context);
    pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
    pd.setCancelable(false);
    pd.setMessage(message);
    pd.show();
}

public static void dismissLoder() {
    pd.dismiss();
}

public static void toast(Context context, String text) {

    Toast.makeText(context, text, Toast.LENGTH_LONG).show();
}
/*
     public static Boolean connection(Context context) {
    ConnectionDetector connection = new ConnectionDetector(context);
    if (!connection.isConnectingToInternet()) {

        Helper.showAlert(context, "No Internet access...!");
        //Helper.toast(context, "No internet access..!");
        return false;
    } else
        return true;
}*/

public static void removeMapFrgment(FragmentActivity fa, int id) {

    android.support.v4.app.Fragment fragment;
    android.support.v4.app.FragmentManager fm;
    android.support.v4.app.FragmentTransaction ft;
    fm = fa.getSupportFragmentManager();
    fragment = fm.findFragmentById(id);
    ft = fa.getSupportFragmentManager().beginTransaction();
    ft.remove(fragment);
    ft.commit();

}

public static AlertDialog showDialog(Context context, String message) {
    AlertDialog.Builder builder = new AlertDialog.Builder(context);
    builder.setMessage(message);

    builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int id) {
            // TODO Auto-generated method stub

        }
    });

    return builder.create();
}

public static void showAlert(Context context, String message) {
    AlertDialog.Builder builder = new AlertDialog.Builder(context);
    builder.setTitle("Alert");
    builder.setMessage(message)
            .setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    dialog.dismiss();
                }
            }).show();
}

public static boolean isURL(String url) {
    if (url == null)
        return false;

    boolean foundMatch = false;
    try {
        Pattern regex = Pattern
                .compile(
                        "\\b(?:(https?|ftp|file)://|www\\.)?[-A-Z0-9+&#/%?=~_|$!:,.;]*[A-Z0-9+&@#/%=~_|$]\\.[-A-Z0-9+&@#/%?=~_|$!:,.;]*[A-Z0-9+&@#/%=~_|$]",
                        Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
        Matcher regexMatcher = regex.matcher(url);
        foundMatch = regexMatcher.matches();
        return foundMatch;
    } catch (PatternSyntaxException ex) {
        // Syntax error in the regular expression
        return false;
    }
}

public static boolean atLeastOneChr(String string) {
    if (string == null)
        return false;

    boolean foundMatch = false;
    try {
        Pattern regex = Pattern.compile("[a-zA-Z0-9]",
                Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
        Matcher regexMatcher = regex.matcher(string);
        foundMatch = regexMatcher.matches();
        return foundMatch;
    } catch (PatternSyntaxException ex) {
        // Syntax error in the regular expression
        return false;
    }
}

public static boolean isValidEmail(String email, Context context) {
    String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
    CharSequence inputStr = email;
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
    Matcher matcher = pattern.matcher(inputStr);
    if (matcher.matches()) {
        return true;
    } else {
        // Helper.toast(context, "Email is not valid..!");

        return false;
    }
}

public static boolean isValidUserName(String email, Context context) {
    String expression = "^[0-9a-zA-Z]+$";
    CharSequence inputStr = email;
    Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
    Matcher matcher = pattern.matcher(inputStr);
    if (matcher.matches()) {
        return true;
    } else {
        Helper.toast(context, "Username is not valid..!");
        return false;
    }
}

public static boolean isValidDateSlash(String inDate) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("dd/mm/yyyy");
    dateFormat.setLenient(false);
    try {
        dateFormat.parse(inDate.trim());
    } catch (ParseException pe) {
        return false;
    }
    return true;
}

public static boolean isValidDateDash(String inDate) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("dd-mm-yyyy");
    dateFormat.setLenient(false);
    try {
        dateFormat.parse(inDate.trim());
    } catch (ParseException pe) {
        return false;
    }
    return true;
}

public static boolean isValidDateDot(String inDate) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
    dateFormat.setLenient(false);
    try {
        dateFormat.parse(inDate.trim());
    } catch (ParseException pe) {
        return false;
    }
    return true;
}

}

答案 29 :(得分:1)

以函数方式存储和检索全局变量。 要进行测试,请确保页面上有Textview项,取消注释代码中的两行并运行。然后再次评论这两行,然后运行 这里TextView的id是用户名和密码。

在您要使用它的每个类中,最后添加这两个例程。 我希望这个例程是全局惯例,但不知道如何。这很有效。

变量随处可见。 它将变量存储在&#34; MyFile&#34;中。你可以按自己的方式改变它。

您使用

调用它
 storeSession("username","frans");
 storeSession("password","!2#4%");***

变量用户名将填入&#34; frans&#34;密码用&#34;!2#4%&#34;。即使重启后它们也可用。

并使用

检索它
 password.setText(getSession(("password")));
 usernames.setText(getSession(("username")));

在grid.java的整个代码下面

    package nl.yentel.yenteldb2;
    import android.content.SharedPreferences;
    import android.os.Bundle;
    import android.support.design.widget.FloatingActionButton;
    import android.support.design.widget.Snackbar;
    import android.support.v7.app.AppCompatActivity;
    import android.support.v7.widget.Toolbar;
    import android.view.View;
    import android.widget.EditText;
    import android.widget.TextView;

    public class Grid extends AppCompatActivity {
    private TextView usernames;
    private TextView password;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_grid);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

      ***//  storeSession("username","frans.eilering@gmail.com");
        //storeSession("password","mijn wachtwoord");***
        password = (TextView) findViewById(R.id.password);
        password.setText(getSession(("password")));
        usernames=(TextView) findViewById(R.id.username);
        usernames.setText(getSession(("username")));
    }

    public void storeSession(String key, String waarde) { 
        SharedPreferences pref = getApplicationContext().getSharedPreferences("MyFile", MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        editor.putString(key, waarde);
        editor.commit();
    }

    public String getSession(String key) {
//http://androidexample.com/Android_SharedPreferences_Basics/index.php?view=article_discription&aid=126&aaid=146
        SharedPreferences pref = getApplicationContext().getSharedPreferences("MyFile", MODE_PRIVATE);
        SharedPreferences.Editor editor = pref.edit();
        String output = pref.getString(key, null);
        return output;
    }

    }
在下面找到textview项目

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="usernames"
    android:id="@+id/username"
    android:layout_below="@+id/textView"
    android:layout_alignParentStart="true"
    android:layout_marginTop="39dp"
    android:hint="hier komt de username" />

 <TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="password"
    android:id="@+id/password"
    android:layout_below="@+id/user"
    android:layout_alignParentStart="true"
    android:hint="hier komt het wachtwoord" />

答案 30 :(得分:1)

这里我创建了一个Helper类来在android中使用首选项。

这是助手类:

public class PrefsUtil {

public static SharedPreferences getPreference() {
    return PreferenceManager.getDefaultSharedPreferences(Applicatoin.getAppContext());
}

public static void putBoolean(String key, boolean value) {
    getPreference().edit().putBoolean(key, value)
            .apply();
}

public static boolean getBoolean(String key) {
    return getPreference().getBoolean(key, false);
}

public static void putInt(String key, int value) {

    getPreference().edit().putInt(key, value).apply();

}

public static void delKey(String key) {

    getPreference().edit().remove(key).apply();

}

}