版权声明:本文为博主原创文章,转载请标明出处。 https://blog.csdn.net/chaoyu168/article/details/53610211
SharedPreferences介绍:
SharedPreferences是Android平台上一个轻量级的存储类,主要是保存一些常用的配置参数,它是采用xml文件存放数据的,文件存放在"/data/data<package name>/shared_prefs"目录下。
SharedPreferences的用法:
由于SharedPreferences是一个接口,而且在这个接口里没有提供写入数据和读取数据的能力。但它是通过其Editor接口中的一些方法来操作SharedPreference的,用法见下面代码:
Context.getSharedPreferences(String name,int mode)来得到一个SharedPreferences实例
name:是指文件名称,不需要加后缀.xml,系统会自动为我们添加上。
mode:是指定读写方式,其值有三种,分别为:Context.MODE_PRIVATE:指定该SharedPreferences数据只能被本应用程序读、写
Context.MODE_WORLD_READABLE:指定该SharedPreferences数据能被其他应用程序读,但不能写
Context.MODE_WORLD_WRITEABLE:指定该SharedPreferences数据能被其他应用程序读写。
结果截图:
工程目录:
Java代码
LoginActivity.java
- <span style="font-family:'Courier New';">package com.liu.activity;
- import android.app.Activity;
- import android.app.backup.SharedPreferencesBackupHelper;
- import android.content.Context;
- import android.content.Intent;
- import android.content.SharedPreferences;
- import android.content.SharedPreferences.Editor;
- import android.os.Bundle;
- import android.text.Spannable;
- import android.view.View;
- import android.view.View.OnClickListener;
- import android.view.Window;
- import android.widget.Button;
- import android.widget.CheckBox;
- import android.widget.CompoundButton;
- import android.widget.CompoundButton.OnCheckedChangeListener;
- import android.widget.EditText;
- import android.widget.ImageButton;
- import android.widget.Toast;
- public class LoginActivity extends Activity {
- private EditText userName, password;
- private CheckBox rem_pw, auto_login;
- private Button btn_login;
- private ImageButton btnQuit;
- private String userNameValue,passwordValue;
- private SharedPreferences sp;
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- //去除标题
- this.requestWindowFeature(Window.FEATURE_NO_TITLE);
- setContentView(R.layout.login);
- //获得实例对象
- sp = this.getSharedPreferences("userInfo", Context.MODE_WORLD_READABLE);
- userName = (EditText) findViewById(R.id.et_zh);
- password = (EditText) findViewById(R.id.et_mima);
- rem_pw = (CheckBox) findViewById(R.id.cb_mima);
- auto_login = (CheckBox) findViewById(R.id.cb_auto);
- btn_login = (Button) findViewById(R.id.btn_login);
- btnQuit = (ImageButton)findViewById(R.id.img_btn);
- //判断记住密码多选框的状态
- if(sp.getBoolean("ISCHECK", false))
- {
- //设置默认是记录密码状态
- rem_pw.setChecked(true);
- userName.setText(sp.getString("USER_NAME", ""));
- password.setText(sp.getString("PASSWORD", ""));
- //判断自动登陆多选框状态
- if(sp.getBoolean("AUTO_ISCHECK", false))
- {
- //设置默认是自动登录状态
- auto_login.setChecked(true);
- //跳转界面
- Intent intent = new Intent(LoginActivity.this,LogoActivity.class);
- LoginActivity.this.startActivity(intent);
- }
- }
- // 登录监听事件 现在默认为用户名为:liu 密码:123
- btn_login.setOnClickListener(new OnClickListener() {
- public void onClick(View v) {
- userNameValue = userName.getText().toString();
- passwordValue = password.getText().toString();
- if(userNameValue.equals("liu")&&passwordValue.equals("123"))
- {
- Toast.makeText(LoginActivity.this,"登录成功", Toast.LENGTH_SHORT).show();
- //登录成功和记住密码框为选中状态才保存用户信息
- if(rem_pw.isChecked())
- {
- //记住用户名、密码、
- Editor editor = sp.edit();
- editor.putString("USER_NAME", userNameValue);
- editor.putString("PASSWORD",passwordValue);
- editor.commit();
- }
- //跳转界面
- Intent intent = new Intent(LoginActivity.this,LogoActivity.class);
- LoginActivity.this.startActivity(intent);
- //finish();
- }else{
- Toast.makeText(LoginActivity.this,"用户名或密码错误,请重新登录", Toast.LENGTH_LONG).show();
- }
- }
- });
- //监听记住密码多选框按钮事件
- rem_pw.setOnCheckedChangeListener(new OnCheckedChangeListener() {
- public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
- if (rem_pw.isChecked()) {
- System.out.println("记住密码已选中");
- sp.edit().putBoolean("ISCHECK", true).commit();
- }else {
- System.out.println("记住密码没有选中");
- sp.edit().putBoolean("ISCHECK", false).commit();
- }
- }
- });
- //监听自动登录多选框事件
- auto_login.setOnCheckedChangeListener(new OnCheckedChangeListener() {
- public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
- if (auto_login.isChecked()) {
- System.out.println("自动登录已选中");
- sp.edit().putBoolean("AUTO_ISCHECK", true).commit();
- } else {
- System.out.println("自动登录没有选中");
- sp.edit().putBoolean("AUTO_ISCHECK", false).commit();
- }
- }
- });
- btnQuit.setOnClickListener(new OnClickListener() {
- @Override
- public void onClick(View v) {
- finish();
- }
- });
- }
- }</span>
LogoActivity.java
- <span style="font-family:'Courier New';">package com.liu.activity;
- import android.app.Activity;
- import android.content.Intent;
- import android.content.SharedPreferences;
- import android.content.SharedPreferences.Editor;
- import android.opengl.ETC1;
- import android.os.Bundle;
- import android.view.View;
- import android.view.View.OnClickListener;
- import android.view.Window;
- import android.view.animation.AlphaAnimation;
- import android.view.animation.Animation;
- import android.view.animation.Animation.AnimationListener;
- import android.widget.Button;
- import android.widget.ImageButton;
- import android.widget.ImageView;
- import android.widget.ProgressBar;
- public class LogoActivity extends Activity {
- private ProgressBar progressBar;
- private Button backButton;
- protected void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- // 去除标题
- this.requestWindowFeature(Window.FEATURE_NO_TITLE);
- setContentView(R.layout.logo);
- progressBar = (ProgressBar) findViewById(R.id.pgBar);
- backButton = (Button) findViewById(R.id.btn_back);
- Intent intent = new Intent(this, WelcomeAvtivity.class);
- LogoActivity.this.startActivity(intent);
- backButton.setOnClickListener(new OnClickListener() {
- @Override
- public void onClick(View v) {
- finish();
- }
- });
- }
- }
- </span>
WelcomeActivity.java
- <span style="font-family:'Courier New';"><span style="BACKGROUND-COLOR: rgb(240,240,240); WHITE-SPACE: pre">package com.liu.activity;</span>
- import android.app.Activity;
- import android.os.Bundle;
- public class WelcomeAvtivity extends Activity {
- @Override
- protected void onCreate(Bundle savedInstanceState) {
- // TODO Auto-generated method stub
- super.onCreate(savedInstanceState);
- setContentView(R.layout.welcome);
- }
- }</span>
布局文件:
login.xml文件
- <span style="font-family:'Courier New';"><?xml version="1.0" encoding="utf-8"?>
- <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- android:background="@drawable/logo_bg"
- android:orientation="vertical" >
- <RelativeLayout
- android:layout_width="fill_parent"
- android:layout_height="wrap_content" >
- <ImageButton
- android:id="@+id/img_btn"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_alignParentRight="true"
- android:background="@drawable/quit"/>
- <TextView
- android:id="@+id/tv_zh"
- android:layout_width="wrap_content"
- android:layout_height="35dip"
- android:layout_marginLeft="12dip"
- android:layout_marginTop="10dip"
- android:gravity="bottom"
- android:text="帐号:"
- android:textColor="#000000"
- android:textSize="18sp" />
- <EditText
- android:id="@+id/et_zh"
- android:layout_width="fill_parent"
- android:layout_height="40dip"
- android:layout_below="@id/tv_zh"
- android:layout_marginLeft="12dip"
- android:layout_marginRight="10dip" />
- <TextView
- android:id="@+id/tv_mima"
- android:layout_width="wrap_content"
- android:layout_height="35dip"
- android:layout_below="@id/et_zh"
- android:layout_marginLeft="12dip"
- android:layout_marginTop="10dip"
- android:gravity="bottom"
- android:text="密码:"
- android:textColor="#000000"
- android:textSize="18sp" />
- <EditText
- android:id="@+id/et_mima"
- android:layout_width="fill_parent"
- android:layout_height="40dip"
- android:layout_below="@id/tv_mima"
- android:layout_marginLeft="12dip"
- android:layout_marginRight="10dip"
- android:maxLines="200"
- android:password="true"
- android:scrollHorizontally="true" />
- <CheckBox
- android:id="@+id/cb_mima"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_below="@id/et_mima"
- android:layout_marginLeft="12dip"
- android:text="记住密码"
- android:textColor="#000000" />
- <CheckBox
- android:id="@+id/cb_auto"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_below="@id/cb_mima"
- android:layout_marginLeft="12dip"
- android:text="自动登录"
- android:textColor="#000000" />
- <Button
- android:id="@+id/btn_login"
- android:layout_width="80dip"
- android:layout_height="40dip"
- android:layout_below="@id/et_mima"
- android:layout_alignParentRight="true"
- android:layout_alignTop="@id/cb_auto"
- android:layout_marginRight="10dip"
- android:gravity="center"
- android:text="登录"
- android:textColor="#000000"
- android:textSize="18sp"/>
- </RelativeLayout>
- </LinearLayout></span>
- <span style="font-family:'Courier New';"><?xml version="1.0" encoding="utf-8"?>
- <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- android:background="@drawable/logo_bg"
- android:orientation="vertical" >
- <RelativeLayout
- android:layout_width="fill_parent"
- android:layout_height="wrap_content"
- android:layout_weight="3">
- <ProgressBar
- android:id="@+id/pgBar"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_centerInParent="true" />
- <TextView
- android:id="@+id/tv1"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_below="@id/pgBar"
- android:layout_centerHorizontal="true"
- android:text="正在登录..."
- android:textColor="#000000"
- android:textSize="18sp" />
- </RelativeLayout>
- <LinearLayout
- android:layout_width="fill_parent"
- android:layout_height="wrap_content"
- android:layout_weight="1"
- android:gravity="center"
- android:orientation="vertical" >
- <Button
- android:id="@+id/btn_back"
- android:layout_width="70dip"
- android:layout_height="35dip"
- android:text="取消"
- android:textColor="#000000"
- android:textSize="12sp" />
- </LinearLayout>
- </LinearLayout></span>
welcome.xml
- <span style="font-family:'Courier New';"><?xml version="1.0" encoding="utf-8"?>
- <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- android:layout_gravity="center"
- android:background="@drawable/login_bg"
- android:orientation="vertical" >
- <TextView
- android:layout_width="fill_parent"
- android:layout_height="wrap_content"
- android:gravity="center"
- android:text="登陆成功,进入用户界面"
- android:textColor="#000000"
- android:textSize="20sp" />
- </LinearLayout></span>