Andriod Studio实现保存QQ密码功能(案例代码详解)

<?xml version=\"1.0\" encoding=\"utf-8\"?>
<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.kh11.MainActivity\">

  <ImageView
    android:id=\"@+id/iv\"
    android:layout_width=\"70dp\"
    android:layout_height=\"70dp\"
    android:layout_centerHorizontal=\"true\"
    android:layout_marginTop=\"40dp\"
    android:background=\"@drawable/touxiang\"/>
  <LinearLayout
    android:id=\"@+id/ll_number\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"wrap_content\"
    android:layout_below=\"@+id/iv\"
    android:layout_centerVertical=\"true\"
    android:layout_marginBottom=\"5dp\"
    android:layout_marginLeft=\"10dp\"
    android:layout_marginRight=\"10dp\"
    android:layout_marginTop=\"15dp\"
    android:background=\"#ffffff\">
    <TextView
      android:id=\"@+id/tv_number\"
      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_number\"
      android:layout_width=\"match_parent\"
      android:layout_height=\"wrap_content\"
      android:layout_marginLeft=\"5dp\"
      android:background=\"@null\"
      android:padding=\"10dp\"/>
  </LinearLayout>
  <LinearLayout
    android:id=\"@+id/ll_password\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"wrap_content\"
    android:layout_below=\"@+id/ll_number\"
    android:layout_centerVertical=\"true\"
    android:layout_marginLeft=\"10dp\"
    android:layout_marginRight=\"10dp\"
    android:background=\"#ffffff\">
    <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_below=\"@+id/ll_password\"
    android:layout_marginLeft=\"10dp\"
    android:layout_marginRight=\"10dp\"
    android:layout_marginTop=\"50dp\"
    android:background=\"#3C8DC4\"
    android:text=\"登录\"
    android:textColor=\"#ffffff\"
    android:textSize=\"20sp\"/>
</RelativeLayout>

package cn.itcast.saveqq;

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

import java.util.HashMap;
import java.util.Map;

public class SPSaveQQ {
  public static boolean saveUserInfo(Context context,String number,String password){
    SharedPreferences sp = context.getSharedPreferences(\"data\",Context.MODE_PRIVATE);
    SharedPreferences.Editor edit = sp.edit();
    edit.putString(\"userName\",number);
    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 number = sp.getString(\"userName\", null);
    String password = sp.getString(\"pwd\", null);
    Map<String ,String > userMap = new HashMap<String,String>();
    userMap.put(\"number\",number);
    userMap.put(\"password\",password);
    return userMap;
  }
}

package com.example.kh11;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import java.util.Map;
import cn.itcast.saveqq.SPSaveQQ;
public class MainActivity extends AppCompatActivity implements View.OnClickListener{
  private EditText etNumber;
  private EditText etPassword;
  private Button btnLogin;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //初始化界面
    initView();
    Map<String ,String > userInfo = SPSaveQQ.getUserInfo(this);
    if(userInfo != null){
      etNumber.setText(userInfo.get(\"number\"));
      etPassword.setText(userInfo.get(\"password\"));
    }
  }
  private void initView(){
    etNumber = (EditText) findViewById(R.id.et_number);
    etPassword = (EditText) findViewById(R.id.et_password);
    btnLogin = (Button) findViewById(R.id.btn_login);
    //设置按钮的点击事件
    btnLogin.setOnClickListener(this);
  }
  @Override
  public void onClick(View v) {
    //当单机登录按钮时，获取QQ账号和密码
    String number = etNumber.getText().toString().trim();
    String password = etPassword.getText().toString();
    //检验账号和密码是否正确
    if(TextUtils.isEmpty(number)){
      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;
    }
    //登陆成功
    Toast.makeText(this,\"登陆成功\",Toast.LENGTH_SHORT).show();
    //保存用户信息
    boolean isSaveSuccess = SPSaveQQ.saveUserInfo(this,number,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();
    }
  }
}