安卓Android本地Sqlite实现注册账号和登录功能

实现了注册账号时将数据写入本地SQLite，登录账号时从本地SQLite匹配数据，并有记住密码功能，以及通过改密口令（类似于密保问题）修改密码的功能

思路很简单，登录账号的时候，先去数据库匹配账号，如果匹配到了相同账号，再去匹配同一行的密码，匹配成功则登录成功，匹配不成功则登录失败。如果没有匹配到账号，则也是登录失败。

注册账号的时候，先去匹配账号是否存在，如果账号存在，则提示账号已经存在，如果数据库中不存欲注册的账号，则允许注册。

在注册的时候，可以通过判断输入内容进行限制，如账号格式，密码位数，改密口令这些，我这里只对密码位数进行了限制。

如果账号界面及登录界面都输入了内容，则进行匹配：

db = new RegisterHelper(this, "user", null, RegisterHelper.REGISTER_DB_VERSION).getReadableDatabase();            Cursor cursor = db.query("user", new String[]{"user", "pass"}, null, null, null, null, null);            boolean login = false;//账号密码是否匹配            //从数据库中匹配账号密码            while (cursor.moveToNext()) {                if (name.equals(cursor.getString(cursor.getColumnIndex("user")))                        && pass.equals(cursor.getString(cursor.getColumnIndex("pass")))) {//用户名匹配后才会去匹配密码：&&逻辑的好处                    login = true;                    break;                }            }

接下来判断login，如果允许登录，则再判断有没有勾选记住密码：

//如果匹配成功，判断是否勾选记住账号，并进行账号信息存储            if (login) {                SharedPreferences.Editor editor = getSharedPreferences("remember", MODE_PRIVATE).edit();//这里利用SharedPreferences进行存储                if (remember.isChecked()) {//如果勾选了记住密码                    editor.putBoolean("remember", true);//是否保存了密码，在这个Activity创建的时候先判断此内容，如果为true则读取并写入输入框，实现记住密码                    editor.putString("name", name);                    editor.putString("pass", pass);                    editor.commit();                } else {                    editor.clear();                }                editor.commit();                Intent intent = new Intent(this, Main_Activity.class);                startActivity(intent);            } else {                //账号密码在数据库中匹配不成功。即login==false                Toast.makeText(this, "账号与密码不匹配", Toast.LENGTH_SHORT).show();            }

在创建Acitivity的时候，判断是否保存了密码，如果保存了，从而实现将保存的密码输入到输入框中，在Activity的onCreate方法中调用此方法就行了

private void isRemember() {        SharedPreferences prefer = getSharedPreferences("remember", MODE_PRIVATE);        boolean isRemember = prefer.getBoolean("remember", false);        if (isRemember) {            et_Name.setText(prefer.getString("name", ""));            et_Pass.setText(prefer.getString("pass", ""));            remember.setChecked(true);        }    }

到这里，登录功能就OK了，但是数据库中根本没有任何一条账号信息！于是，当然少不了注册功能--往数据库里写入账号信息！

创建一个注册账号的layout和activity，进行代码编写

主要功能实现：当用户输入你所需求的信息，并符合要求（如密码不能低于6位等），接下来就去匹配数据库了，首先判断账号是否已经存在于数据库：

<pre name="code" class="java">            boolean creatUser=false;//是否允许创建用户            dbHelper = new RegisterHelper(Register_Activity.this, "user", null, 1);            SQLiteDatabase db = dbHelper.getWritableDatabase();            Cursor cursor = db.query("user", new String[]{"user"}, null, null, null, null, null);            while (cursor.moveToNext()) {                if (user_name.equals(cursor.getString(cursor.getColumnIndex("user")))) {//如果在数据库中找到了该账号，则不允许创建                    Toast.makeText(Register_Activity.this, "该账户已存在", Toast.LENGTH_SHORT).show();//弹一条吐司提醒用户                    creatUser = false;//不允许创建                }            }

接下来判断creatUser到底允许不允许创建用户，从而实现向数据库写入账号信息的逻辑：

<pre name="code" class="java">if (creatUser) {//如果允许创建用户

<span style="white-space:pre"></span>//将用户信息以键值对形式存贮在ContentValues中                ContentValues values = new ContentValues();                values.put("user", user_name);                values.put("pass", pass1);                values.put("name", name);                values.put("reSetPass", gmkl);                db.insert("user", null, values);//插入数据

<span style="white-space:pre"></span>//注册成功后弹出一个Dialog提示用户                AlertDialog.Builder dialog = new AlertDialog.Builder(Register_Activity.this);                dialog.setTitle("注册成功");                dialog.setMessage("您已成功注册账户，请返回登录界面");

<span style="white-space:pre"></span>//设置确认按钮，跳转至登录界面                dialog.setPositiveButton("返回登录界面", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        finish();                    }                });

<span style="white-space:pre"></span>//设置取消按钮，留在注册界面                dialog.setNegativeButton("留在注册界面", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                    }                });                dialog.show();            }

到这里，登录和注册功能就实现了！

还有一个修改密码（找回密码）的功能：

由于手欠，将此功能写在了一个自定义的Dialog里，其实可以写在Dialog类型的Activity中的，这里我就不再修改了

首先验证用户是否完整输入了我们改密所需要的各项内容，如果都输入了，则在数据库中匹配账号，账号匹配成功则再匹配改密口令，如果改密口令匹配成功，则修改密码，代码如下：

<span style="white-space:pre"></span>    db = new RegisterHelper(context, "user", null, RegisterHelper.REGISTER_DB_VERSION).getReadableDatabase();            Cursor cursor = db.query("user", new String[]{"user", "reSetPass"}, null, null, null, null, null);            //验证账号与改密口令是否相符            while (cursor.moveToNext()) {                if (userName.equals(cursor.getString(cursor.getColumnIndex("user")))&&                        gmkl.equals(cursor.getString(cursor.getColumnIndex("reSetPass")))) {//如果账号相符，则匹配改密口令，与登录类似                        ContentValues values = new ContentValues();                        values.put("pass", newPass);                        db.update("user", values, "user=?", new String[]{userName});//更新密码                        Toast.makeText(context,"密码修改成功！\n请牢记新密码并使用新密码登录",Toast.LENGTH_LONG).show();//弹出吐司提醒用户                        isReSetPassFinish=true;//改密工作完成                        break;                }            }            //未成功匹配账号&改密口令            if (!isReSetPassFinish){                Toast.makeText(context,"账号不存在或改密口令错误",Toast.LENGTH_LONG).show();            }

下面我就将这两个Activity的代码以及修改密码的代码无情的全部贴上来吧：

LoginActivity：

package com.example.application.activity;import android.app.Activity;import android.content.Intent;import android.content.SharedPreferences;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.os.Bundle;import android.view.View;import android.view.Window;import android.widget.ArrayAdapter;import android.widget.Button;import android.widget.CheckBox;import android.widget.EditText;import android.widget.ImageView;import android.widget.ListView;import android.widget.PopupWindow;import android.widget.Toast;import com.example.application.Dialog.ReSetPass_Dialog;import com.example.application.R;import com.example.application.db.RegisterHelper;/** * 登录界面 * Created by lxb on 2016/5/13. */public class Login_Activity extends Activity implements View.OnClickListener {    private Button bt_login;    private Button bt_cancel;    private Button bt_register;    private Button bt_reSetPass;    private EditText et_Name;    private EditText et_Pass;    private CheckBox remember;    private ImageView showUserName;    private SQLiteDatabase db;    private PopupWindow popup;    private ArrayAdapter<String> popupAdpter;    private ListView popupLV;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        requestWindowFeature(Window.FEATURE_NO_TITLE);        setContentView(R.layout.login_layout);        bt_login = (Button) findViewById(R.id.bt_login);        bt_cancel = (Button) findViewById(R.id.bt_cancel);        bt_register = (Button) findViewById(R.id.bt_register);        bt_reSetPass = (Button) findViewById(R.id.bt_reSetPass);        et_Name = (EditText) findViewById(R.id.et_loginName);        et_Pass = (EditText) findViewById(R.id.et_loginPass);        remember = (CheckBox) findViewById(R.id.cb_rememberName);        showUserName = (ImageView) findViewById(R.id.iv_showName);        showUserName.setOnClickListener(this);        bt_login.setOnClickListener(this);        bt_cancel.setOnClickListener(this);        bt_register.setOnClickListener(this);        bt_reSetPass.setOnClickListener(this);        isRemember();    }    /**     * Button监听器     *     * @param v     */    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.bt_login: {                Login();            }            break;            case R.id.bt_register: {                Intent intent = new Intent(Login_Activity.this, Register_Activity.class);                startActivity(intent);            }            break;            case R.id.iv_showName: {                InitPopup();            }            break;            case R.id.bt_reSetPass: {                ReSetPass_Dialog dialog=new ReSetPass_Dialog(this);                dialog.show();            }            break;            case R.id.bt_cancel: {                System.exit(0);            }        }    }    /**     * 登录账号验证     * 判断是否勾选记住密码     */    private void Login() {        String name = et_Name.getText().toString();        String pass = et_Pass.getText().toString();        //判断是否输入内容        if (name.equals("") || pass.equals("")) {            Toast.makeText(this, "请输入账号或密码", Toast.LENGTH_SHORT).show();        } else {//输入了账号&密码            db = new RegisterHelper(this, "user", null, RegisterHelper.REGISTER_DB_VERSION).getReadableDatabase();            Cursor cursor = db.query("user", new String[]{"user", "pass"}, null, null, null, null, null);            boolean login = false;//账号密码是否匹配            //从数据库中匹配账号密码            while (cursor.moveToNext()) {                if (name.equals(cursor.getString(cursor.getColumnIndex("user")))                        && pass.equals(cursor.getString(cursor.getColumnIndex("pass")))) {                    login = true;                    break;                }            }            //如果匹配成功，判断是否勾选记住账号，并进行账号信息存储            if (login) {                SharedPreferences.Editor editor = getSharedPreferences("remember", MODE_PRIVATE).edit();                if (remember.isChecked()) {                    editor.putBoolean("remember", true);                    editor.putString("name", name);                    editor.putString("pass", pass);                    editor.commit();                } else {                    editor.clear();                }                editor.commit();                Intent intent = new Intent(this, Main_Activity.class);                startActivity(intent);            } else {                //账号密码在数据库中匹配不成功                Toast.makeText(this, "账号与密码不匹配", Toast.LENGTH_SHORT).show();            }        }    }    private void InitPopup() {    }    /**     * 判断是否是否保存过密码     */    public void isRemember() {        SharedPreferences prefer = getSharedPreferences("remember", MODE_PRIVATE);        boolean isRemember = prefer.getBoolean("remember", false);        if (isRemember) {            et_Name.setText(prefer.getString("name", ""));            et_Pass.setText(prefer.getString("pass", ""));            remember.setChecked(true);        }    }}

RegisterActivity：

package com.example.application.activity;import android.app.Activity;import android.content.ContentValues;import android.content.DialogInterface;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.os.Bundle;import android.support.v7.app.AlertDialog;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.Toast;import com.example.application.R;import com.example.application.db.RegisterHelper;/** * Created by lxb on 2016/5/14. */public class Register_Activity extends Activity implements View.OnClickListener {    private Button register_go;    private Button register_cancel;    private EditText register_user_name;    private EditText register_user_pass1;    private EditText register_user_pass2;    private EditText register_name;    private EditText register_gmkl;    private RegisterHelper dbHelper;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.register_layout);        register_user_name = (EditText) findViewById(R.id.register_user_name);        register_user_pass1 = (EditText) findViewById(R.id.register_pass1);        register_user_pass2 = (EditText) findViewById(R.id.register_pass2);        register_name = (EditText) findViewById(R.id.register_name);        register_gmkl = (EditText) findViewById(R.id.register_gmkl);        register_go = (Button) findViewById(R.id.register_go);        register_cancel = (Button) findViewById(R.id.register_cancel);        register_go.setOnClickListener(this);        register_cancel.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.register_go: {                RegisterSave();            }            break;            case R.id.register_cancel: {                finish();            }        }    }    private void RegisterSave() {        String user_name = register_user_name.getText().toString();        String pass1 = register_user_pass1.getText().toString();        String pass2 = register_user_pass2.getText().toString();        String name = register_name.getText().toString();        String gmkl = register_gmkl.getText().toString();        boolean creatUser = true;        if (user_name.equals("") || pass1.equals("") || pass2.equals("") || name.equals("") || gmkl.equals("")) {            Toast.makeText(this, "请完整输入各项注册内容", Toast.LENGTH_SHORT).show();        } else if (!pass1.equals(pass2)) {            Toast.makeText(this, "两次输入密码不一致，请重新输入", Toast.LENGTH_SHORT).show();        } else if (pass1.length() < 6) {            Toast.makeText(this, "密码小于六位数，请重新输入", Toast.LENGTH_SHORT).show();        } else {            dbHelper = new RegisterHelper(Register_Activity.this, "user", null, 1);            SQLiteDatabase db = dbHelper.getWritableDatabase();            Cursor cursor = db.query("user", new String[]{"user"}, null, null, null, null, null);            while (cursor.moveToNext()) {                if (user_name.equals(cursor.getString(cursor.getColumnIndex("user")))) {                    Toast.makeText(Register_Activity.this, "该账户已存在", Toast.LENGTH_SHORT).show();                    creatUser = false;                }            }            if (creatUser) {                ContentValues values = new ContentValues();                values.put("user", user_name);                values.put("pass", pass1);                values.put("name", name);                values.put("reSetPass", gmkl);                db.insert("user", null, values);                AlertDialog.Builder dialog = new AlertDialog.Builder(Register_Activity.this);                dialog.setTitle("注册成功");                dialog.setMessage("您已成功注册账户，请返回登录界面");                dialog.setPositiveButton("返回登录界面", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        finish();                    }                });                dialog.setNegativeButton("留在注册界面", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                    }                });                dialog.show();            }        }    }}

ReSetPass_Dialog：

package com.example.application.Dialog;import android.app.Dialog;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.Toast;import com.example.application.R;import com.example.application.db.RegisterHelper;/** * 修改密码的Dialog * Created by lxb on 2016/5/15. */public class ReSetPass_Dialog extends Dialog implements View.OnClickListener{    private Context context;    private EditText et_reSetUserName;    private EditText et_reSetGmkl;    private EditText et_reSetNewPass;    private Button bt_reSetGo;    private Button bt_reSetCancel;    private SQLiteDatabase db;    public ReSetPass_Dialog(Context context) {        super(context);        this.context=context;    }    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        this.setContentView(R.layout.resetpass_dialog);        et_reSetGmkl = (EditText) findViewById(R.id.et_reSetGmkl);        et_reSetUserName = (EditText) findViewById(R.id.et_reSetUserName);        et_reSetNewPass = (EditText) findViewById(R.id.et_reSetNewPass);        bt_reSetGo= (Button) findViewById(R.id.bt_reSetGo);        bt_reSetCancel= (Button) findViewById(R.id.bt_reSetCancel);        bt_reSetGo.setOnClickListener(this);        bt_reSetCancel.setOnClickListener(this);    }    @Override    public void onClick(View v) {        switch (v.getId()){            case R.id.bt_reSetGo:{                if (isReSetPass()){                    dismiss();                }            }            break;            case R.id.bt_reSetCancel:{                cancel();            }            break;        }    }    /**     *     * 账号与改密口令验证     * 修改密码     *     * @return 是否完成完成改密工作     */    private boolean isReSetPass() {        boolean isReSetPassFinish=false;        String userName = et_reSetUserName.getText().toString();        String gmkl = et_reSetGmkl.getText().toString();        String newPass = et_reSetNewPass.getText().toString();        //是否完整输入各项内容        if (userName.equals("") || gmkl.equals("") || newPass.equals("")) {            Toast.makeText(context, "请输入改密所需的每项内容", Toast.LENGTH_SHORT).show();        } else {//完整输入了各项所需内容            db = new RegisterHelper(context, "user", null, RegisterHelper.REGISTER_DB_VERSION).getReadableDatabase();            Cursor cursor = db.query("user", new String[]{"user", "reSetPass"}, null, null, null, null, null);            //验证账号与改密口令是否相符            while (cursor.moveToNext()) {                if (userName.equals(cursor.getString(cursor.getColumnIndex("user")))&&                        gmkl.equals(cursor.getString(cursor.getColumnIndex("reSetPass")))) {                        ContentValues values = new ContentValues();                        values.put("pass", newPass);                        db.update("user", values, "user=?", new String[]{userName});                        Toast.makeText(context,"密码修改成功！\n请牢记新密码并使用新密码登录",Toast.LENGTH_LONG).show();                        isReSetPassFinish=true;                        break;                }            }            //未成功匹配账号&改密口令            if (!isReSetPassFinish){                Toast.makeText(context,"账号不存在或改密口令错误",Toast.LENGTH_LONG).show();            }        }        return isReSetPassFinish;    }}

应该很清楚了