Android中基于Sqlite实现注册和登录功能，供大家参考，具体内容如下
前言
写这篇博客主要是为了巩固一下学的Sqlite知识以及梳理一下这个项目的逻辑
实现逻辑
项目的图片结构图如下
代码
user class
public class User {
private String name; //用户名
private String password; //密码
public User(String name, String password) {
this.name = name;
this.password = password;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}DBOpenHelper class
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import java.util.ArrayList;
public class DBOpenHelper extends SQLiteOpenHelper {
private SQLiteDatabase db;
public DBOpenHelper(Context context){//打开数据库
super(context,"db_test",null,1);//1：上下文，2：数据库名，3：允许我们查询数据时返回一个Cursor，4：当前数据库的版本号
db = getReadableDatabase();
}
@Override
public void onCreate(SQLiteDatabase db){//建表（user）语句
db.execSQL("CREATE TABLE IF NOT EXISTS user(" +//PRIMARY key 将id设为主键 ，AUTOINCREMENT 设置id列自为增长
"_id INTEGER PRIMARY KEY AUTOINCREMENT," +
"name TEXT," + //text 文本类型
"password TEXT)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){//重写升级
db.execSQL("DROP TABLE IF EXISTS user");
onCreate(db);
}
public void add(String name,String password){//重写添加
db.execSQL("INSERT INTO user (name,password) VALUES(?,?)",new Object[]{name,password});
}
public void delete(String name,String password){//重写删除
db.execSQL("DELETE FROM user WHERE name = AND password ="+name+password);
}
public void updata(String password){//重写更新
db.execSQL("UPDATE user SET password = ?",new Object[]{password});
}
public ArrayList<User> getAllData(){//将表内信息返回成一个list
ArrayList<User> list = new ArrayList<User>();
Cursor cursor = db.query("user",null,null,null,null,null,"name DESC");//1表名，2列，3行，4行，5指定列进行过滤，6进一步过滤。7得到的信息进行排序（desc逆序）
while(cursor.moveToNext()){//一行一行遍历
String name = cursor.getString(cursor.getColumnIndex("name"));//移动到name列，读取出来
String password = cursor.getString(cursor.getColumnIndex("password"));
list.add(new User(name,password));//添加到user 的list中
}
return list;//把list返回
}
}activity_login.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#eeeeee"
tools:context=".LoginActivity">
<RelativeLayout
android:id="@+id/rl_loginactivity_top"
android:layout_width="match_parent"
android:layout_height="70dp"
>
<ImageView
android:id="@+id/iv_loginactivity_back"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_alignParentTop="true"
android:layout_marginLeft="10dp"
android:layout_marginTop="20dp"
android:clickable="true" />
<TextView
android:id="@+id/tv_loginactivity_login"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="登录"
android:textColor="#3A5FCD"
android:textSize="20dp"
android:layout_toRightOf="@+id/iv_loginactivity_back"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:layout_marginLeft="30dp"
/>
<TextView
android:id="@+id/tv_loginactivity_register"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="注册"
android:textColor="#3A5FCD"
android:textSize="20dp"
android:layout_centerVertical="true"
android:layout_alignParentRight="true"
android:layout_marginRight="30dp"
android:clickable="true"
android:onClick="onClick"
/>
</RelativeLayout>
<LinearLayout
android:id="@+id/ll_loginactivity_two"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_below="@+id/rl_loginactivity_top"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_loginactivity_username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="用户名："/>
<EditText
android:id="@+id/et_loginactivity_username"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="手机号/邮箱/用户名"/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_loginactivity_password"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="密 码："/>
<EditText
android:id="@+id/et_loginactivity_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="登录密码"
android:inputType="textPassword"/>
</LinearLayout>
</LinearLayout>
<Button
android:id="@+id/bt_loginactivity_login"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/ll_loginactivity_two"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:text="登录"
android:textColor="#3A5FCD"
android:gravity="center"
android:onClick="onClick"
/>
</RelativeLayout>LoginActivity
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
public class LoginActivity extends AppCompatActivity implements View.OnClickListener {
private DBOpenHelper mDBOpenHelper;
private EditText mEtLoginactivityUsername;
private EditText mEtLoginactivityPassword;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
initView();
mDBOpenHelper = new DBOpenHelper(this);
}
private void initView() {
// 初始化控件
mEtLoginactivityUsername = findViewById(R.id.et_loginactivity_username);
mEtLoginactivityPassword = findViewById(R.id.et_loginactivity_password);
// 设置点击事件监听器
}
public void onClick(View view) {
switch (view.getId()) {
// 跳转到注册界面
case R.id.tv_loginactivity_register:
startActivity(new Intent(this, RegisterActivity.class));
finish();
break;
case R.id.bt_loginactivity_login:
String name = mEtLoginactivityUsername.getText().toString().trim();//.trim（）删除两边的空格
String password = mEtLoginactivityPassword.getText().toString().trim();
if (!TextUtils.isEmpty(name) && !TextUtils.isEmpty(password)) {//TextUtils.isEmpty（）输入框是空值或者你就敲了几下空格键该方法都会返回true
ArrayList<User> data = mDBOpenHelper.getAllData();//data为获取的user表内的user信息
boolean match = false;
for (int i = 0; i < data.size(); i++) {//遍历比较
User user = data.get(i);//获取data里的第i个user信息
if (name.equals(user.getName()) && password.equals(user.getPassword())) {//将信息与输入的信息进行对比
match = true;
break;
} else {
match = false;
}
}
if (match) {
Toast.makeText(this, "登录成功", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
finish();//销毁此Activity
} else {
Toast.makeText(this, "用户名或密码不正确，请重新输入", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(this, "请输入你的用户名或密码", Toast.LENGTH_SHORT).show();
}
break;
}
}
}activity_register.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#eeeeee"
tools:context=".RegisterActivity">
<RelativeLayout
android:id="@+id/rl_registeractivity_top"
android:layout_width="match_parent"
android:layout_height="70dp"
>
<ImageView
android:id="@+id/iv_registeractivity_back"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_centerVertical="true"
android:layout_marginLeft="10dp"
android:clickable="true"
/>
<TextView
android:id="@+id/tv_registeractivity_register"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="注册"
android:textColor="#3A5FCD"
android:textSize="20dp"
android:layout_centerVertical="true"
android:layout_marginLeft="20dp"
/>
</RelativeLayout>
<LinearLayout
android:id="@+id/ll_registeractivity_body"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_below="@+id/rl_registeractivity_top"
android:layout_marginTop="10dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
>
<!-- 第一个文本编辑框 输入用户名 -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_registeractivity_username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="用户名："/>
<EditText
android:id="@+id/et_registeractivity_username"
android:layout_width="match_parent"
android:layout_height="50dp"
android:hint="请输入用户名"
android:gravity="center_vertical"
android:layout_marginLeft="10dp"
/>
</LinearLayout>
<!-- 第二个文本编辑框 输入密码 -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:id="@+id/tv_registeractivity_password1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="密 码："/>
<EditText
android:id="@+id/et_registeractivity_password"
android:layout_width="match_parent"
android:layout_height="50dp"
android:gravity="center_vertical"
android:layout_marginLeft="10dp"
android:inputType="textPassword"
android:hint="请输入密码" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginRight="15dp"
android:layout_marginTop="10dp"
android:orientation="horizontal" />
<!-- 注册按钮 -->
<Button
android:id="@+id/bt_registeractivity_register"
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_marginLeft="5dp"
android:textColor="#3A5FCD"
android:text="注册"
android:layout_marginTop="40dp"
android:onClick="onClick"
/>
</LinearLayout>
</RelativeLayout>RegisterActivity
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
public class RegisterActivity extends AppCompatActivity implements View.OnClickListener {
private DBOpenHelper mDBOpenHelper;
private Button mBtRegisteractivityRegister;
private ImageView mIvRegisteractivityBack;
private EditText mEtRegisteractivityUsername;
private EditText mEtRegisteractivityPassword;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
initView();
mDBOpenHelper = new DBOpenHelper(this);
}
private void initView(){
mEtRegisteractivityUsername = findViewById(R.id.et_registeractivity_username);
mEtRegisteractivityPassword = findViewById(R.id.et_registeractivity_password);
}
public void onClick(View view) {
switch (view.getId()) {
case R.id.iv_registeractivity_back: //返回登录页面
Intent intent1 = new Intent(this, LoginActivity.class);
startActivity(intent1);
finish();
break;
case R.id.bt_registeractivity_register: //注册按钮
//获取用户输入的用户名、密码、验证码
String username = mEtRegisteractivityUsername.getText().toString().trim();
String password = mEtRegisteractivityPassword.getText().toString().trim();
//注册验证
if (!TextUtils.isEmpty(username) && !TextUtils.isEmpty(password)) {
mDBOpenHelper.add(username, password);//将用户名和密码加入到数据库的表内中
Intent intent2 = new Intent(this, LoginActivity.class);
startActivity(intent2);
finish();
Toast.makeText(this, "验证通过，注册成功", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, "未完善信息，注册失败", Toast.LENGTH_SHORT).show();
}
break;
}
}
}实现效果
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
