使用SharedPreferences进行数据的存储实例：增删改查联系人界面

效果描述：

在目标界面中，有两个文本编辑框，用于输入姓名和电话号码。然后有4个按钮，分别是：添加，查询，删除和更新。

该工程下载地址

效果图如下所示：

实现方法

将姓名和电话号码作为一个整体保存到SharedPreferences中，这个过程需要转码，具体如下.

页面布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
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"
android:background="@drawable/b1" >

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginTop="10dp">

<EditText
android:id="@+id/name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="在这里编辑姓名"
android:ems="10" >

<requestFocus />
</EditText>

<EditText
android:id="@+id/phone"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:hint="在这里编辑电话号码"
android:inputType="phone" />

</LinearLayout>

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_marginTop="10dp">

<Button
android:id="@+id/find"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="查询"
android:layout_marginLeft="10dp"/>

<Button
android:id="@+id/add"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="添加"
android:layout_marginLeft="30dp"/>

</LinearLayout>

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_marginTop="10dp">

<Button
android:id="@+id/delate"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="删除"
android:layout_marginLeft="10dp"/>

<Button
android:id="@+id/refresh"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="更新"
android:layout_marginLeft="30dp"/>

</LinearLayout>

<View
android:layout_marginTop="6dp"
android:layout_marginLeft="5dp"
android:layout_width="260dp"
android:layout_height="2dp"
android:background="#8ec7e2"/>

<EditText
android:id="@+id/show"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:hint="在此显示联系人信息"
android:inputType="textMultiLine" />

</LinearLayout>

保存姓名和电话号码的people类

package com.example.p1;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Map;

public class People implements Serializable
{
ArrayList<String> names=null;
ArrayList<String> phones=null;

}

事件响应

package com.example.p1;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.app.Activity;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.util.Base64;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity
{
private static final String FILENAME = "people";
private static final int MODE = MODE_PRIVATE;
EditText name,phone=null;
Button find,add,refresh,delate=null;
EditText show=null;
SharedPreferences shared=null;
People people=new People();
String showInformation=new String("");

@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

name=(EditText) findViewById(R.id.name);
phone=(EditText) findViewById(R.id.phone);
find=(Button) findViewById(R.id.find);
add=(Button) findViewById(R.id.add);
refresh=(Button) findViewById(R.id.refresh);
delate=(Button) findViewById(R.id.delate);
show=(EditText) findViewById(R.id.show);
shared=getSharedPreferences(FILENAME, MODE);
people.names=new ArrayList();
people.phones=new ArrayList();

//点击添加按钮，响应响应的动作事件
add.setOnClickListener(new OnClickListener()
{

@Override
public void onClick(View arg0)
{
if(name.getText()!=null && phone.getText()!=null)
{
if(!"".equals(name.getText().toString()) &&!"".equals(phone.getText().toString()))
{
people.names.add(name.getText().toString());
people.phones.add(phone.getText().toString());
ByteArrayOutputStream baos=new ByteArrayOutputStream();

try
{
ObjectOutputStream oos=new ObjectOutputStream(baos);
oos.writeObject(people);
String peopleBase64=new String(Base64.encode(baos.toByteArray(), Base64.DEFAULT));
Editor editor=shared.edit();

ebe4
editor.putString("people", peopleBase64);
editor.commit();

if("".equals(showInformation))
{
showInformation=name.getText().toString()+" "+phone.getText().toString()+"\n";
}
else
{
showInformation +=name.getText().toString()+" "+phone.getText().toString()+"\n";
}

show.setText(showInformation);
name.setText("");
phone.setText("");
Toast.makeText(MainActivity.this, "信息添加成功！", Toast.LENGTH_LONG).show();

}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
else
{
Toast.makeText(MainActivity.this, "请填写完整！", Toast.LENGTH_LONG).show();
}
}
}
});

//点击查询按钮，响应相应的动作事件
find.setOnClickListener(new OnClickListener()
{

@Override
public void onClick(View arg0)
{
String peopleBase64=shared.getString("people", "none");

if(name.getText()!=null && phone.getText()!=null)
{
if(!"".equals(name.getText().toString()) && !"".equals(phone.getText().toString()))
{
String tempName=name.getText().toString();
String tempPhone=phone.getText().toString();
int flag1=0;
int flag2=0;

for(int i=0;i<people.names.size();i++)
{
String temp=people.names.get(i);
if(temp.equals(tempName))
flag1=1;
}
for(int i=0;i<people.phones.size();i++)
{
String temp=people.phones.get(i);
if(temp.equals(tempPhone))
flag2=1;
}

if(flag1==1 && flag2==1)
Toast.makeText(MainActivity.this, "查询成功！", Toast.LENGTH_LONG).show();
else
Toast.makeText(MainActivity.this, "查询失败！", Toast.LENGTH_LONG).show();
}
}
else
{
Toast.makeText(MainActivity.this, "请输入查询内容！", Toast.LENGTH_LONG).show();
}
}
});

//为删除添加动作事件
delate.setOnClickListener(new OnClickListener()
{

@Override
public void onClick(View arg0)
{
String tempName=name.getText().toString();
String tempPhone=phone.getText().toString();

if(name.getText()!=null && phone.getText()!=null)
{
if(!"".equals(name.getText().toString()) && !"".equals(phone.getText().toString()))
{
int flag=0;

for(int i=0;i<people.names.size();i++)
{
String temp1=people.names.get(i);
String temp2=people.phones.get(i);
if(temp1.equals(tempName) && temp2.equals(tempPhone))
{
people.names.remove(i);
people.phones.remove(i);
flag=1;
}
}

if(flag==1)
Toast.makeText(MainActivity.this, "删除成功！", Toast.LENGTH_LONG).show();
else
Toast.makeText(MainActivity.this, "删除失败！", Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(MainActivity.this, "删除的内容不存在！", Toast.LENGTH_LONG).show();
}
}
else
{
Toast.makeText(MainActivity.this, "删除的内容不能为空！", Toast.LENGTH_LONG).show();
}
}
});

//为更新按钮添加动作事件
refresh.setOnClickListener(new OnClickListener()
{

@Override
public void onClick(View arg0)
{
String tempShow="";
for(int i=0;i<people.names.size();i++)
{
tempShow=tempShow+people.names.get(i)+" "+people.phones.get(i)+"\n";
}

show.setText(tempShow);
}
});
}

@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;
}

}

文件的保存路径与内容

打开DDMS，从FileExplorer中找到data/data,在com.example.p1(包名)目录下找到shared_prefs的pepple(文件名),然后导出查看。保存的转换成Base64编码。