安卓SharedPreferences类的使用

 1 package com.lidaochen.phonecall;
 2 
 3 import android.content.Intent;
 4 import android.content.SharedPreferences;
 5 import android.net.Uri;
 6 import android.os.Environment;
 7 import android.support.v7.app.AppCompatActivity;
 8 import android.os.Bundle;
 9 import android.text.TextUtils;
10 import android.util.Log;
11 import android.view.View;
12 import android.widget.Button;
13 import android.widget.CheckBox;
14 import android.widget.EditText;
15 import android.widget.TabHost;
16 import android.widget.ThemedSpinnerAdapter;
17 import android.widget.Toast;
18 
19 import java.util.Map;
20 
21 public class MainActivity extends AppCompatActivity{
22     private EditText et_userName;
23     private EditText et_pwd;
24     private CheckBox cb;
25     private SharedPreferences sp;
26     @Override
27     protected void onCreate(Bundle savedInstanceState) {
28         super.onCreate(savedInstanceState);
29         setContentView(R.layout.activity_main);
30         // 初始化sp实例
31         sp = getSharedPreferences("test", 0);
32 
33         // 1.获取控件
34         et_userName = (EditText)findViewById(R.id.et_username);
35         et_pwd = (EditText)findViewById(R.id.et_pwd);
36         cb = (CheckBox)findViewById(R.id.cb);
37         // 把我们需要的数据在test.xml中显示出来，然后在控件上显示出来
38         String name = sp.getString("name", "");
39         String pwd = sp.getString("pwd", "");
40         // 将数据显示在控件上
41         et_userName.setText(name);
42         et_pwd.setText(pwd);
43     }
44     // 按钮点击事件
45     public void login(View v)
46     {
47         // 获取userName和pwd
48         String name = et_userName.getText().toString().trim();
49         String pwd = et_pwd.getText().toString().trim();
50         // 判断name和pwd是否为空
51         if(TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd))
52         {
53             Toast.makeText(MainActivity.this, "用户名或密码不能为空", Toast.LENGTH_LONG).show();
54         }
55         else
56         {
57             System.out.println("登录之后要干的事情！");
58             if(cb.isChecked())
59             {
60                // 获取sp的编辑器
61                 SharedPreferences.Editor edit = sp.edit();
62                 edit.putString("name", name);
63                 edit.putString("pwd", pwd);
64                 // 把edit进行提交
65                 edit.commit();
66                 Toast.makeText(MainActivity.this, "保存成功！", Toast.LENGTH_LONG).show();
67             }
68             else
69             {
70                 Toast.makeText(MainActivity.this, "请勾选复选框", Toast.LENGTH_LONG).show();
71             }
72         }
73     }
74 }