编辑sharedpreference中的数据

 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();

从sharedpreference中检索数据

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);
  }*/
}

Edit

我从API Demo样本中截取了这个片段。它有一个编辑文本框。在这种情况下，它不是必需的。我也有同样的看法。

您可以使用以下方法保存值:

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();
    }

使用这个方法，你可以从SharedPreferences中获取值:

public String getPreferences(Context context, String prefKey) {
  SharedPreferences sharedPreferences = PreferenceManager
 .getDefaultSharedPreferences(context);
 return sharedPreferences.getString(prefKey, "");
}

这里prefKey是用来保存特定值的键。谢谢。

SharedPreferences的基本思想是将内容存储在XML文件中。

Declare your xml file path.(if you don't have this file, Android will create it. If you have this file, Android will access it.) SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE); Write value to Shared Preferences prefs.edit().putLong("preference_file_key", 1010101).apply(); the preference_file_key is the name of shared preference files. And the 1010101 is the value you need to store. apply() at last is to save the changes. If you get error from apply(), change it to commit(). So this alternative sentence is prefs.edit().putLong("preference_file_key", 1010101).commit(); Read from Shared Preferences SharedPreferences sp = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE); long lsp = sp.getLong("preference_file_key", -1); lsp will be -1 if preference_file_key has no value. If 'preference_file_key' has a value, it will return the value of this.

整个代码是

    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.

阅读的代码是

    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

以函数的方式存储和检索全局变量。 要测试，请确保页面上有Textview项，取消代码中的两行注释并运行。然后再次注释这两行，然后运行。 这里TextView的id是用户名和密码。

在你想要使用它的每个Class中，在最后添加这两个例程。 我想这个例行程序是全球例行程序，但不知道如何。这个作品。

这些变量随处可见。 它将变量存储在“MyFile”中。你可以按自己的方式改变。

你称之为使用

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

变量username将用“frans”填充，密码为“!2#4%”。即使在重新启动后，它们仍然可用。

你用

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

下面是我的grid.java的全部代码

    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;
    }

    }

下面是textview项

<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" />

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.

你需要在AdapterClass或任何其他类中使用SharedPreferences。 那一次只是使用这个声明和使用相同的屁股上面。

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

//here context is your application context

用于字符串或布尔值

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

取数据与上面相同

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

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:“temp”为sharedpreferences名称，“name”为输入值。如果value不存在，则返回null