Android学习笔记之数据的共享存储SharedPreferences
（1）布局文件，一个简单的登录文件;
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="22dp"
android:layout_marginTop="22dp"
android:text="用户名：" />
<EditText
android:id="@+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/textView1"
android:layout_alignBottom="@+id/textView1"
android:layout_toRightOf="@+id/textView1"
android:ems="10" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="@+id/textView1"
android:layout_below="@+id/editText1"
android:layout_marginTop="17dp"
android:text="密码：" />
<EditText
android:id="@+id/editText2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/editText1"
android:layout_below="@+id/editText1"
android:ems="10"
android:inputType="textPassword" >
<requestFocus />
</EditText>
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/checkBox1"
android:layout_marginLeft="34dp"
android:layout_marginTop="32dp"
android:layout_toRightOf="@+id/button1"
android:text="取消" />
<CheckBox
android:id="@+id/checkBox1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_below="@+id/editText2"
android:layout_marginTop="22dp"
android:text="记住用户名" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/button2"
android:layout_alignBottom="@+id/button2"
android:layout_alignLeft="@+id/editText2"
android:text="登录" />
<CheckBox
android:id="@+id/checkBox2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/checkBox1"
android:layout_alignBottom="@+id/checkBox1"
android:layout_marginLeft="14dp"
android:layout_toRightOf="@+id/button1"
android:text="静音登录" />
</RelativeLayout>
（2）目录结构：
（3）SharedPreferences的工具类LoginService.java
package com.lc.data_storage_share.sharepreference;
import java.util.Map;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
public class LoginService {
private Context context; // 上下文
public LoginService(Context context) {
this.context = context;
}
/*
* 保存登录信息
*/
public boolean saveLoginMsg(String name, String password) {
boolean flag = false;
// 不要加后缀名，系统自动以.xml的格式保存
// 这里的login是要存放的文件名
SharedPreferences preferences = context.getSharedPreferences("login",
context.MODE_PRIVATE + context.MODE_APPEND);
Editor editor = preferences.edit();
editor.putString("name", name);
editor.putString("password", password);
flag = editor.commit();
return flag;
}
/*
* 保存文件
*/
public boolean saveSharePreference(String filename, Map<String, Object> map) {
boolean flag = false;
SharedPreferences preferences = context.getSharedPreferences(filename,
Context.MODE_PRIVATE);
/*
* 存数据的时候要用到Editor
*/
Editor editor = preferences.edit();
for (Map.Entry<String, Object> entry : map.entrySet()) {
String key = entry.getKey();
Object object = entry.getValue();
if (object instanceof Boolean) {
Boolean new_name = (Boolean) object;
editor.putBoolean(key, new_name);
} else if (object instanceof Integer) {
Integer integer = (Integer) object;
editor.putInt(key, integer);
} else if (object instanceof Float) {
Float f = (Float) object;
editor.putFloat(key, f);
} else if (object instanceof Long) {
Long l = (Long) object;
editor.putLong(key, l);
} else if (object instanceof String) {
String s = (String) object;
editor.putString(key, s);
}
}
flag = editor.commit();
return flag;
}
/*
* 读取文件
*/
public Map<String, ?> getSharePreference(String filename) {
Map<String, ?> map = null;
SharedPreferences preferences = context.getSharedPreferences(filename,
Context.MODE_PRIVATE);
/*
* 读数据的饿时候只需要访问即可
*/
map = preferences.getAll();
return map;
}
}
（3）MainActivity.java
package com.lc.data_storage_share;
import java.util.HashMap;
import java.util.Map;
import com.example.data_storage_share.R;
import com.lc.data_storage_share.sharepreference.LoginService;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
/*
* 单元测试的时候需要在清单文件中
*/
public class MainActivity extends Activity {
private Button button1;// 登录
private Button button2;// 取消
private EditText editText1, editText2;
private CheckBox checkBox1;// 记住密码
private CheckBox checkBox2; // 静音登录
private LoginService service;
Map<String, ?> map = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1 = (Button) this.findViewById(R.id.button1);
button2 = (Button) this.findViewById(R.id.button2);
editText1 = (EditText) this.findViewById(R.id.editText1);
editText2 = (EditText) this.findViewById(R.id.editText2);
checkBox1 = (CheckBox) this.findViewById(R.id.checkBox1);
checkBox2 = (CheckBox) this.findViewById(R.id.checkBox2);
service = new LoginService(this);
map = service.getSharePreference("login");
if (map != null && !map.isEmpty()) {
editText1.setText(map.get("username").toString());
checkBox1.setChecked((Boolean) map.get("isName"));
checkBox2.setChecked((Boolean) map.get("isquiet"));
}
button1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (editText1.getText().toString().trim().equals("admin")) {
Map<String, Object> map1 = new HashMap<String, Object>();
if (checkBox1.isChecked()) {
map1.put("username", editText1.getText().toString()
.trim());
}else {
map1.put("username", "");
}
map1.put("isName", checkBox1.isChecked());
map1.put("isquiet", checkBox2.isChecked());
service.saveSharePreference("login", map1);
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
（4）测试类：
package com.lc.data_storage_share;
import java.util.HashMap;
import java.util.Map;
import android.test.AndroidTestCase;
import android.util.Log;
import com.lc.data_storage_share.sharepreference.LoginService;
public class MyTest extends AndroidTestCase {
private final String TAG = "MyTest";
public MyTest() {
// TODO Auto-generated constructor stub
}
/*
* 登录
*/
public void save() {
LoginService service = new LoginService(getContext());
boolean flag = service.saveLoginMsg("admin", "123");
Log.i(TAG, "-->>" + flag);
}
/*
* 保存文件
*/
public void saveFile() {
LoginService service = new LoginService(getContext());
Map<String, Object> map = new HashMap<String, Object>();
map.put("name", "jack");
map.put("age", 23);
map.put("salary", 23000.0f);
map.put("id", 1256423132l);
map.put("isManager", true);
boolean flag = service.saveSharePreference("msg", map);
Log.i(TAG, "-->>" + flag);
}
/*
* 读取文件
*/
public void readFile() {
LoginService service = new LoginService(getContext());
Map<String, ?> map = service.getSharePreference("msg");
Log.i(TAG, "-->>" + map.get("name"));
Log.i(TAG, "-->>" + map.get("age"));
Log.i(TAG, "-->>" + map.get("salary"));
Log.i(TAG, "-->>" + map.get("isManager"));
Log.i(TAG, "-->>" + map.get("id"));
}
}
如何添加Junit测试单元：
1.在清单文件中添加：
2.在application中添加：
3.测试类MyTest要继承AndroidTestCase
（5）结果，下次登录的时候会记着用户名
