利用SQLite数据库进行用户名、密码的注册和登录验证

利用SQLite数据库进行存储用户名、密码等等其他信息

首先是activity_main布局界面

底下的两个按钮，“注册”是跳转到注册用户名和密码界面；“随便看看”是跳过注册登录页面，直接进入到主程序，方便路人进行浏览操作。

接下来是注册页面的布局zhuce.xml

下面是MainActivity.class

package com.example.android_login;
import android.os.Bundle;
import android.app.Activity;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.app.AlertDialog; 

public class MainActivity extends Activity {
	private TextView textview;
	//数据库名称
		private static final String DATABASE_NAME="yufengtest.db";
		
		//数据库版本号
		private static final int DATABASE_VERSION=1;
		//表名		
		private static final String TABLE_NAME="username";
		private DatebaseHelper databaseHelper;
		private SQLiteDatabase db;
		private Button button1;
		private EditText nameText,passText;
    private Intent intent;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		this.requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.activity_main);
		
		nameText=(EditText)findViewById(R.id.username);
		passText=(EditText)findViewById(R.id.pasw);
		
		button1=(Button)findViewById(R.id.tijiao);
		textview=(TextView)findViewById(R.id.zhuce);
		textview.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				intent=new Intent(MainActivity.this,zhuce.class);
				startActivity(intent);
			}
			
		});	
		 
		//启动注册页面
		 TextView textview=(TextView)findViewById(R.id.zhuce);
		 textview.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				Intent a=new Intent(MainActivity.this,zhuce.class);
				startActivity(a);
			}
			 
		 });
		 
		 //启动随便看看页面
		 TextView textview1=(TextView)findViewById(R.id.suibian);
		 textview1.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				Intent a=new Intent(MainActivity.this,Main.class);
				startActivity(a);
			}
			 
		 });
	        button1.setOnClickListener(new LoginListener());  		
	}
	
	
	 class LoginListener implements OnClickListener{
		 public void onClick(View v){
		 String nameString =nameText.getText().toString();
		 String passString=passText.getText().toString();
		 if(nameString.equals("")||passString.equals(""))
		   {
			 //弹出消息框
			 new AlertDialog.Builder(MainActivity.this).setTitle("错误")  
            .setMessage("帐号或密码不能空").setPositiveButton("确定", null)  
            .show();  
		   }else{
			   isUserinfo(nameString,passString);
		   }
		 }
	 }

	public Boolean isUserinfo(String name,String pass)
	{
		String nameString=name;
		String passString=pass;
		databaseHelper=new DatebaseHelper(MainActivity.this,DATABASE_NAME,null,DATABASE_VERSION);
		db =  databaseHelper.getReadableDatabase();
		try{		
			Cursor cursor=db.query(TABLE_NAME, new String[]{"name","password"},"name=?",new String[]{nameString},null,null,"password");
			while(cursor.moveToNext())
			{
				String password=cursor.getString(cursor.getColumnIndex("password"));
				
				
				if(passString.equals(password))
				{
					 new AlertDialog.Builder(MainActivity.this).setTitle("正确")  
	                 .setMessage("成功登录").setPositiveButton("确定", new DialogInterface.OnClickListener() {
						
						@Override
						public void onClick(DialogInterface dialog, int which) {
							// TODO Auto-generated method stub
							Intent a=new Intent(MainActivity.this,Main.class);
							startActivity(a);
						}
					}).show();  
	                 
					break;
				}
				else
				{
					Toast.makeText(this, "用户名密码不正确",Toast.LENGTH_LONG).show();
					break;
				}
			}
			
			
			
               
		}catch(SQLiteException e){  
            CreatTable();  
        }  
        return false;  
	}
	 
	

	private void CreatTable() {
		// TODO Auto-generated method stub
		String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME
				+ " (name varchar(30) primary key,password varchar(30));";
		try{
			db.execSQL(sql);
		}catch(SQLException ex){}
	}


	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

package com.example.android_login;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class DatebaseHelper extends SQLiteOpenHelper {
	//数据库名称
	private static final String DATABASE_NAME="yufengtest.db";
	
	//数据库版本号
	private static final int DATABASE_VERSION=1;
	
	//数据库SQL语句 添加一个表

	public DatebaseHelper(Context context, String name, CursorFactory factory,
			int version) {
		super(context, DATABASE_NAME, factory, DATABASE_VERSION);
		// TODO Auto-generated constructor stub
	}

	@Override
	public void onCreate(SQLiteDatabase db) {
		// TODO Auto-generated method stub
      db.execSQL("create table username( name varchar(30) primary key,password varchar(30))");
	}

	@Override
	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
		// TODO Auto-generated method stub

	}

}

package com.example.android_login;

import android.app.Activity;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class zhuce extends Activity {
	private EditText edittext1,edittext2,edittext3;
	private Button button;
	private DatebaseHelper databaseHelper;
	//数据库名称
	private static final String DATABASE_NAME="yufengtest.db";
	//数据库版本号
	private static final int DATABASE_VERSION=1;
	
	private static final String TABLE_NAME="username";
	private SQLiteDatabase db;
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		this.requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.zhuce);
		edittext1=(EditText)findViewById(R.id.editview1);
		edittext2=(EditText)findViewById(R.id.editview2);
		edittext3=(EditText)findViewById(R.id.editview3);

		button=(Button)findViewById(R.id.tijiao);
        button.setOnClickListener(new OnClickListener(){
        	
        	
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				String namestring = edittext1.getText().toString();
	    		String passstring = edittext2.getText().toString();
	    		String repassstring=edittext3.getText().toString();
	    		if(passstring.equals(repassstring))
	    		{
				databaseHelper=new DatebaseHelper(zhuce.this,DATABASE_NAME,null,DATABASE_VERSION);
				db =  databaseHelper.getReadableDatabase();
				db.execSQL("insert into username (name,password) values(?,?)",new String[]{namestring,passstring});
			    
				Toast.makeText(zhuce.this, "注册成功！", Toast.LENGTH_LONG).show();
				Intent b=new Intent(zhuce.this,MainActivity.class);
				startActivity(b);
			    }
	    		else
	    		{
	    			Toast.makeText(zhuce.this,"两次密码不一致", Toast.LENGTH_LONG).show();
	    		}
			}
        	
        });
   }
	
	
}

点击dialog对话框中的“确定”按钮，会跳转到程序的主界面去，相当于直接点击“随便看看”按钮，大家可以自己编写后面的程序