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

使用SharedPreference实例，可以使用getInt(String key, int defVal)检索任意首选项的int值。在这种情况下，我们更倾向于使用计数器。

在我们的例子中，我们可以使用edit()并使用putInt(String key, int newVal)来修改SharedPreference实例。我们增加了应用程序的计数，这些计数超出了应用程序并相应地显示。

为了进一步演示这一点，再次重新启动应用程序，您将注意到每次重新启动应用程序时计数都会增加。

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
    }
}

main。xml

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>

最好的实践

创建命名为PreferenceManager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:用SP_TITLE替换你的SharedPreference键。

例子:

存储字符串在shareperence:

setString("my_key", "my_value");

从shareperence获取字符串:

String strValue = getString("my_key");

希望这对你有所帮助。

我想在这里补充一点，当使用SharedPreferences时，这个问题的大多数代码片段都有类似MODE_PRIVATE的东西。MODE_PRIVATE意味着无论您写入这个共享首选项的是什么，都只能由您的应用程序读取。

Whatever key you pass to getSharedPreferences() method, android creates a file with that name and stores the preference data into it. Also remember that getSharedPreferences() is supposed to be used when you intend to have multiple preference files for your application. If you intend to use single preference file and store all key-value pairs into it then use the getSharedPreference() method. Its weird why everyone (including myself) simply uses getSharedPreferences() flavor without even understanding the difference between the above two.

下面的视频教程应该会有所帮助 https://www.youtube.com/watch?v=2PcAQ1NBy98

2.用于存储在共享优先级

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

2.用于检索相同的用途

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

简单的方法:

保存:

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

检索:

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

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", "");