package com.example.day10_26;

import java.util.Map;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {
    private EditText et1;
    private EditText et2;
    private Button bu1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et1 = (EditText) findViewById(R.id.et1);
        et2 = (EditText) findViewById(R.id.et2);
        bu1 = (Button) findViewById(R.id.bu1);
        Map<String, String> userInfo = SPSaveQQ.getUserInfo(this);
        if (userInfo != null) {
            et1.setText(userInfo.get("account"));
            et2.setText(userInfo.get("passeord"));
        }

    }

    public void Click(View view) {
        // Toast.makeText(MainActivity.this, "登录成功", Toast.LENGTH_SHORT);
        switch (view.getId()) {

        case R.id.bu1:
            String account = et1.getText().toString().trim();
            String password = et2.getText().toString();
            if (TextUtils.isEmpty(account)) {
                Toast.makeText(MainActivity.this, "请输入QQ账号", Toast.LENGTH_SHORT)
                        .show();
                return;
            }
            if (TextUtils.isEmpty(password)) {
                Toast.makeText(MainActivity.this, "请输入密码", Toast.LENGTH_SHORT).show();
                return;
            }
            Toast.makeText(MainActivity.this, "登录成功", Toast.LENGTH_SHORT).show();
            boolean isSaveSuccee = SPSaveQQ.saveUserInfo(MainActivity.this,
                    account, password);
            if (isSaveSuccee) {
                Toast.makeText(MainActivity.this, "保存成功", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(MainActivity.this, "保存失败", Toast.LENGTH_SHORT).show();
            }
            break;
        default:
            break;
        }
    }
}

package com.example.day10_26;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import android.content.Context;
import android.content.SharedPreferences;

public class SPSaveQQ {
    /**
     * 保存数据
     * 
     * @param context
     * @param account
     * @param password
     * @return
     */

    public static boolean saveUserInfo(Context context, String account,
            String password) {
        SharedPreferences sp = context.getSharedPreferences("data",
                Context.MODE_PRIVATE);
        SharedPreferences.Editor edit = sp.edit();
        edit.putString("userName", account);
        edit.putString("pwd", password);
        edit.commit();
        return true;

    }

    public static Map<String, String> getUserInfo(Context context) {
        SharedPreferences sp = context.getSharedPreferences("data", Context.MODE_PRIVATE);
        String account = sp.getString("userName", null);
        String password = sp.getString("pwd", null);
        Map<String,String> userMap = new HashMap<String, String>();
        userMap.put("account", account);
        userMap.put("passeord", password);
        return userMap;
    }
}

<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="com.example.homework2.MainActivity" >
    
    <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="90dp"
        android:text="账号"
        android:textSize="30sp" 
        android:background="#FFFFFF"
        />

    <EditText
        android:id="@+id/et1"
        android:layout_width="200sp"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/tv1"
        android:layout_alignParentRight="true"
        android:layout_alignTop="@+id/tv1"
        android:layout_toRightOf="@+id/tv1"
        android:phoneNumber="true"
        android:background="#FFFFFF"
        android:textSize="20sp" >
    </EditText>
    
    <TextView
        android:id="@+id/tv2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="140sp"
        android:text="密码"
        android:textSize="30sp" 
        android:background="#FFFFFF"
        />
    
    <EditText
        android:id="@+id/et2"
        android:layout_width="200sp"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/tv2"
        android:layout_alignParentRight="true"
        android:layout_alignTop="@+id/tv2"
        android:layout_toRightOf="@+id/tv2"
        android:password="true"
        android:background="#FFFFFF"
        android:textSize="20sp" >
    </EditText>

     <TextView
         android:id="@+id/tv3"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_below="@+id/bt1"
         android:layout_centerHorizontal="true"
         android:layout_marginTop="98dp"
         android:textSize="30sp" />

     <ImageView
         
         android:layout_width="45sp"
         android:layout_height="45sp"
         android:layout_above="@+id/et1"
         android:layout_centerHorizontal="true"
         android:src="@drawable/ic_launcher"
         android:layout_marginBottom="18dp" />

     <Button
         android:id="@+id/bu1"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_alignLeft="@+id/tv2"
         android:layout_below="@+id/tv2"
         android:layout_marginTop="69dp"
         android:background="#63B8FF"
         android:onClick="Click"
         android:text="登录"
         android:textSize="30sp" />
    
</RelativeLayout>