Android SharedPreferences一般的读写 的用法。

 1 package com.lixu.testsharepreferences;
 2 
 3 import android.app.Activity;
 4 import android.content.Context;
 5 import android.content.SharedPreferences;
 6 import android.content.SharedPreferences.Editor;
 7 import android.os.Bundle;
 8 import android.widget.Toast;
 9 
10 public class MainActivity extends Activity {
11 
12     private static final String USER_NAME = "username";
13     private static final String USER_PWS = "userpws";
14     private String NAME = "name";
15 
16     @Override
17     protected void onCreate(Bundle savedInstanceState) {
18         super.onCreate(savedInstanceState);
19         setContentView(R.layout.activity_main);
20         writeSharedPreferences();
21         readSharedPreferences();
22 
23     }
24 
25     // Context.MODE_PRIVATE 这个是设置访问权限 意思是只有本app可以读写里面的数据
26     // 如果SharedPreferences里面没有写入数据 就返回"无值"；
27     private void readSharedPreferences() {
28         SharedPreferences sp = this.getSharedPreferences(NAME, Context.MODE_PRIVATE);
29 
30         String str1 = sp.getString(USER_NAME, "无值");
31         String str2 = sp.getString(USER_PWS, "无值");
32 
33         Toast.makeText(getApplicationContext(), "用户名是：" + str1, 1).show();
34 
35         Toast.makeText(getApplicationContext(), "用户密码是：" + str2, 1).show();
36 
37     }
38 
39     private void writeSharedPreferences() {
40         SharedPreferences sp = this.getSharedPreferences(NAME, Context.MODE_PRIVATE);
41 
42         Editor edt = sp.edit();
43         edt.putString(USER_NAME, "lixu");
44         edt.putString(USER_PWS, "123456789");
45         // 提交
46         edt.commit();
47 
48     }
49 
50 }