Question

请帮助我，因为我是android的初学者。在此我可以使用相同的用户名和电子邮件ID注册多次，以便如何获得唯一的用户名和电子邮件ID。还有如何将单选按钮值（男性或女性）添加到数据库中。我可以从微调器中选择多个值并显示到数据库中..提前感谢。

这是Register.java文件。

package com.example.login;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

public class Register extends Activity implements OnItemSelectedListener {

EditText fname, lname, emailid, username, pass, cpass;
RadioGroup selection;
RadioButton male, female;
Spinner usrtyp, hobbies;
TextView type, hoby;
Button submit;
ContentValues values;
SQLiteDatabase db;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.register);

    db = openOrCreateDatabase("login", MODE_PRIVATE, null);
    db.execSQL(
            "CREATE TABLE IF NOT EXISTS USERS (ID integer PRIMARY KEY AUTOINCREMENT, F_NAME VARCHAR(200), L_NAME VARCHAR(200), EMAIL_ID VARCHAR(20), GENDER VARCHAR(20), USERNAME VARCHAR(200), PASSWORD VARCHAR(16), C_PASSWORD VARCHAR(16), HOBBIES VARCHAR(200), USER_TYPE VARCHAR(200));");

    values = new ContentValues();

    fname = (EditText) findViewById(R.id.firstname);
    lname = (EditText) findViewById(R.id.lastname);
    emailid = (EditText) findViewById(R.id.emailid);
    selection = (RadioGroup) findViewById(R.id.radioGroup1);
    male = (RadioButton) findViewById(R.id.male);
    female = (RadioButton) findViewById(R.id.female);
    username = (EditText) findViewById(R.id.username);
    pass = (EditText) findViewById(R.id.password);
    cpass = (EditText) findViewById(R.id.cpassword);
    hoby = (TextView) findViewById(R.id.tvhobbies);
    hobbies = (Spinner) findViewById(R.id.spinner2);
    type = (TextView) findViewById(R.id.usertype);
    usrtyp = (Spinner) findViewById(R.id.spinner1);
    submit = (Button) findViewById(R.id.submit);



    // Hobbies
    hobbies.setOnItemSelectedListener(this);

    List<String> hoby = new ArrayList<String>();
    hoby.add("Sports");
    hoby.add("Movies");
    hoby.add("Travelling");
    hoby.add("Reading");

    ArrayAdapter<String> dataadapter = new ArrayAdapter<String>(this, android.R.layout.simple_dropdown_item_1line,
            hoby);
    dataadapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
    hobbies.setAdapter(dataadapter);

    // User Type
    usrtyp.setOnItemSelectedListener(this);

    List<String> user = new ArrayList<String>();
    user.add("Admin");
    user.add("Normal User");

    ArrayAdapter<String> dataadapter1 = new ArrayAdapter<String>(this, android.R.layout.simple_dropdown_item_1line,
            user);
    dataadapter1.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
    usrtyp.setAdapter(dataadapter1);

    submit.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            try {
                String firstName = fname.getText().toString();
                String lastName = lname.getText().toString();
                String Email_ID = emailid.getText().toString();
                String Gender = male.getText().toString();
                String userName = username.getText().toString();
                String Password = pass.getText().toString();
                String confirmPassword = cpass.getText().toString();
                String Hobbies = hobbies.getSelectedItem().toString();
                String userType = usrtyp.getSelectedItem().toString();


                //Check vacant
                if (firstName.equals("") || lastName.equals("") || Email_ID.equals("") || userName.equals("")
                        || Password.equals("") || confirmPassword.equals("")) {
                    Toast.makeText(getApplicationContext(), "Fill Vacant", Toast.LENGTH_LONG).show();
                    return;
                }

                //check if password doesn't match
                if (!Password.equals(confirmPassword)) {
                    Toast.makeText(getApplicationContext(), "Password doesn't match", Toast.LENGTH_LONG).show();
                    return;
                } 
                else

                values.put("F_NAME", firstName);
                values.put("L_NAME", lastName);
                values.put("EMAIL_ID", Email_ID);
                values.put("USERNAME", userName);
                values.put("PASSWORD", Password);
                values.put("GENDER", Gender);
                values.put("C_PASSWORD", confirmPassword);
                values.put("HOBBIES", Hobbies);
                values.put("USER_TYPE", userType);

                db.insert("USERS", null, values);

            } catch (Exception e) {
                System.out.println(e);
            }
            Toast.makeText(getApplicationContext(), "Successfully submited", Toast.LENGTH_LONG).show();
            Intent i = new Intent(getApplicationContext(), Login.class);
            startActivity(i);
        }
    });
}

@Override
public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
    // TODO Auto-generated method stub

}

@Override
public void onNothingSelected(AdapterView<?> arg0) {
    // TODO Auto-generated method stub

}

}

Login.java文件..

package com.example.login;

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

public class Login extends Activity implements OnClickListener {

EditText uname, pass;
Button login;
SQLiteDatabase db;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.signin);

    uname = (EditText) findViewById(R.id.loginusername);
    pass = (EditText) findViewById(R.id.loginpassword);
    login = (Button) findViewById(R.id.login);

    db = openOrCreateDatabase("login", MODE_PRIVATE, null);

    login.setOnClickListener(this);
}

@Override
public void onClick(View arg0) {
    // TODO Auto-generated method stub
    try {
        String user_Name = uname.getText().toString();
        String Password1 = pass.getText().toString();

        // If username or password is not entered
        if (user_Name.equals("") || Password1.equals("")) {
            Toast.makeText(getApplicationContext(), "Please enter Username and      Password", Toast.LENGTH_LONG).show();
            return;
        } else {
            String query = "SELECT * FROM USERS WHERE userName = '" + user_Name + "' AND Password = '" + Password1
                    + "'";

            Cursor c = db.rawQuery(query, null);

            if (c.moveToFirst()) {

                Intent i = new Intent(Login.this, Home.class);
                i.putExtra("un", user_Name);
                startActivity(i);
            } else {
                Toast.makeText(getApplicationContext(), "Wrong Username or Password", Toast.LENGTH_LONG).show();
                return;
            }
        }

    } catch (Exception e) {
        System.out.println(e);
    }
}

}

Home.java文件。

package com.example.login;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class Home extends Activity {

TextView tv1;
ListView lv;
String un;
SQLiteDatabase db;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.home);

    lv = (ListView) findViewById(R.id.listView);
    tv1 = (TextView) findViewById(R.id.textView1);
    db = openOrCreateDatabase("login", MODE_PRIVATE, null);

    Intent ii = getIntent();
    Bundle b = ii.getExtras();

    String temp = (String) b.get("un");
    tv1.setText("Welcome " + temp);


    int c=0;

    try {

        String query1 = "SELECT * FROM USERS;";
        Cursor c1 = db.rawQuery(query1, null);
        if(c1.moveToFirst()){
            String[] temp2 = new String[c1.getCount()];
            do{
                String tempo =c1.getString(0) + " " + c1.getString(1) + " " + c1.getString(2) + " " + c1.getString(4) + " " + c1.getString(8) + " " + c1.getString(9);


                temp2[c]=tempo;
                c++;
                //Toast.makeText(getApplicationContext(), c1.getString(1), Toast.LENGTH_LONG).show();

            }
            while(c1.moveToNext());

            ArrayAdapter<String> adp = new ArrayAdapter(getApplicationContext(),android.R.layout.simple_list_item_1, temp2);
            lv.setAdapter(adp);

        }

    } catch (Exception e) {
        System.out.println(e);
    }

}

}

Answer 1

SQLite提供的表中已有唯一的ID，请尝试：

select rowid,* from USERS

第一列将是自动生成的ID。

Answer 2

"CREATE TABLE IF NOT EXISTS USERS (ID integer PRIMARY KEY AUTOINCREMENT,
 F_NAME VARCHAR(200), 
L_NAME VARCHAR(200), 
EMAIL_ID VARCHAR(20) UNIQUE,
 GENDER VARCHAR(20),
 USERNAME VARCHAR(200) UNIQUE, 
PASSWORD VARCHAR(16), 
C_PASSWORD VARCHAR(16),
 HOBBIES VARCHAR(200), 
USER_TYPE VARCHAR(200));");

现在你不能重复用户名和电子邮件。我建议在性别列使用1或0时使用char。我不知道你的意思是说显示到数据库

Answer 3

通过写这个，我得到了唯一的电子邮件ID：

String id = "SELECT * FROM USERS WHERE Email_ID = '" + Email_ID + "'";
                Cursor c2 = db.rawQuery(id, null);
                if (c2.getCount() > 0) {
                    Toast.makeText(getApplicationContext(), "Email ID already exists", Toast.LENGTH_LONG).show();
                    return;
                }

用户名相同。

如何获得唯一的用户名，电子邮件ID？以及如何在数据库中获取单选按钮值（男性或女性）。

3 个答案: