第八个作业 QQ账号的保存

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

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

public class FileSaveQQ {
    public static boolean saveUserIfo(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("password",password );
        return userMap;
    }
    

}

import android.support.v7.app.ActionBarActivity;
import android.text.TextUtils;

import java.util.Map;

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity{
    private EditText et_account;
    private EditText et_password;
    private Button btn_login;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_account=(EditText)findViewById(R.id.et_account);
        et_password=(EditText)findViewById(R.id.et_password);
        btn_login =(Button)findViewById(R.id.btn_login);
        Map<String, String>userInfo=FileSaveQQ.getUserInfo(this);
        if(userInfo !=null) {
            et_account.setText(userInfo.get("account"));
            et_password.setText(userInfo.get("password"));
        }
    }


        
    
    public void Click(View v) {
        switch(v.getId()) {
            case R.id.btn_login:
                String account = et_account.getText().toString().trim();
                String password = et_password.getText().toString();
                if(TextUtils.isEmpty(account)) {
                    Toast.makeText(this, "请输入QQ账号", Toast.LENGTH_SHORT).show();
                    return;
                }
                if(TextUtils.isEmpty(password)) {
                    Toast.makeText(this, "请输入密码", Toast.LENGTH_SHORT).show();
                    return;
                }
                Toast.makeText(this, "登陆成功", Toast.LENGTH_SHORT).show();
                boolean isSaveSuccess = FileSaveQQ.saveUserIfo(this, account, password);
                if(isSaveSuccess) {
                    Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show();
                }else {
                    Toast.makeText(this, "保存失败", Toast.LENGTH_SHORT).show();
                }
                break;
            
        }
    }

    
}

 <ImageView 
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:layout_centerHorizontal="true"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="30dp"
        android:src="@drawable/ic_luncher02"
        />
    <LinearLayout 
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginTop="15dp"
         android:background="@android:color/white"
         android:orientation="horizontal">
          <TextView
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:padding="10dp"
              android:text="账号"
              android:textColor="#000"
              android:textSize="20sp"
             />
         <EditText
              android:id="@+id/et_account"
              android:layout_width="match_parent"
                 android:layout_height="wrap_content"
              android:layout_marginLeft="5dp"
              android:background="@null"
              android:padding="10dp"
             />
         </LinearLayout>
         <LinearLayout 
                android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:layout_marginTop="10dp"
                android:background="@android:color/white"
                 android:orientation="horizontal">
             
             <TextView 
                 android:id="@+id/tv_password"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:padding="10dp"
                 android:text="密码"
                 android:textColor="#000"
                 android:textSize="20sp" 
                 />
             <EditText
              android:id="@+id/et_password"
              android:layout_width="match_parent"
                 android:layout_height="wrap_content"
              android:layout_marginLeft="5dp"
              android:background="@null"
              android:inputType="textPassword"
              android:padding="10dp"/>
         </LinearLayout>
         <Button 
             android:id="@+id/btn_login"
             android:layout_width="match_parent"
                android:layout_height="wrap_content"
             android:layout_marginTop="25dp"
             android:background="#3c8dc4"
             android:text="登录"
             android:textColor="@android:color/white"
             android:textSize="20sp"
             android:onClick="Click"
             />