Question

我正在尝试创建一个应用程序，我有dbhelper with insert，每当我尝试登录我的应用程序时，它说我的数据库中没有项目，我不明白为什么，我正在努力超过一个月，请帮助。我的dbhelper

package com.example.nir.nestleapp;


import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import java.util.HashMap;

public class MyDBHandler extends SQLiteOpenHelper {
    public static final int DATABASE_VERSION = 3;
    public static final String DATABASE_NAME = "UsersTable.db";
    public static final String Table_Name = "UsersTable";
    public static final String KEY_User = "User";
    public static final String KEY_Password = "Password";
    public static final String KEY_FullName = "FullName";
    public static final String KEY_PhoneNumber="PhoneNumber";
    public static final String KEY_IDNUMBER="IDNumber";
    public static final String[] DB_COL=new String[]{KEY_User, KEY_Password, KEY_FullName, KEY_PhoneNumber, KEY_IDNUMBER};

    public MyDBHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String CreateTableSql = "CREATE TABLE " + Table_Name + " ( " +
                KEY_User + " INTEGER PRIMARY KEY AUTOINCREMENT , " +
                KEY_Password + " TEXT , " +
                KEY_FullName + " TEXT , "+
                KEY_PhoneNumber+" TEXT , "+
                KEY_IDNUMBER+ " ) ";
        db.execSQL(CreateTableSql);
    }@Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + Table_Name);
        onCreate(db);
    }

    public void Add(UserTable NewUser) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(KEY_User,NewUser.GetUserName() );
        values.put(KEY_Password, NewUser.GetPassword());
        values.put(KEY_FullName,NewUser.GetFullName());
        values.put(KEY_PhoneNumber,NewUser.GetPhoneNumber());
        values.put(KEY_IDNUMBER,NewUser.GetID());
        db.insert(Table_Name, null, values);
        db.close();
    }
}

这是我的登录活动：

package com.example.nir.nestleapp;

import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.opengl.EGLDisplay;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import java.lang.reflect.GenericArrayType;
import java.util.ArrayList;

import static com.example.nir.nestleapp.MyDBHandler.KEY_IDNUMBER;

public class LoginActivity extends AppCompatActivity {
    private SQLiteDatabase _database=null;
    private MyDBHandler db=null;
    Cursor c;
    public DrawerLayout mDrawer;
    public ActionBarDrawerToggle mToggle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);
        db=new MyDBHandler(this);
        _database=this.openOrCreateDatabase(db.DATABASE_NAME, MODE_PRIVATE,null);
        SQLiteDatabase database=db.getReadableDatabase();
        c=database.query(db.Table_Name,db.DB_COL,null,null,null,null,null);
        c.moveToFirst();
        mDrawer = (DrawerLayout) findViewById(R.id.activity_login);
        mToggle = new ActionBarDrawerToggle(this, mDrawer, R.string.open, R.string.close);
        mDrawer.addDrawerListener(mToggle);
        mToggle.syncState();
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        final TextView RegisterPage = (TextView) findViewById(R.id.textView4);
        TextView Text1 = (TextView) findViewById(R.id.textView3);
        Button GuestLogin = (Button) findViewById(R.id.LoginGuestBtn);
        RegisterPage.setTextSize(17);
        Text1.setTextSize(17);
        RegisterPage.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(LoginActivity.this, RegisterActivity.class));
            }
        });
        GuestLogin.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(LoginActivity.this, MainPageActivity.class));
            }
        });
    }
    public void LoginIntent(View view) {
        EditText LoginUser = (EditText) findViewById(R.id.LoginUser);
        EditText LoginPass = (EditText) findViewById(R.id.LoginPassword);
        if (LoginUser.getText().toString().isEmpty() || LoginPass.getText().toString().isEmpty()) {
            Toast.makeText(LoginActivity.this, "אנא מלא את כל הפרטים", Toast.LENGTH_SHORT).show();
            return;
        }
        c.moveToFirst();
        if (c.getCount() == 0) {
            Toast.makeText(this, "NO ITEMS IN DB", Toast.LENGTH_SHORT).show();
            return;
        }
        if (c.moveToFirst()) {
            while (!c.isAfterLast()) {
                if (c.getString(0).equals(LoginUser.getText().toString()) && c.getString(1).equals(LoginPass.getText().toString())) {
                    Toast.makeText(LoginActivity.this, "!", Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(LoginActivity.this, MainPageActivity.class));
                    return;
                } else c.moveToNext();
            }
        }
        Toast.makeText(LoginActivity.this, "!!", Toast.LENGTH_SHORT).show();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.navigation_drawer, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (mToggle.onOptionsItemSelected(item)) {
            return true;
        }
        switch (item.getItemId()) {
            case R.id.MainPage:
                startActivity(new Intent(this, MainPageActivity.class));
                break;
        }
        return super.onOptionsItemSelected(item);
    }


}

这是我的注册活动：

package com.example.nir.nestleapp;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;



public class RegisterActivity extends AppCompatActivity {
    MyDBHandler db=new MyDBHandler(this);
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);
        TextView RegisterHead = (TextView) findViewById(R.id.RegisterHeadline);
        RegisterHead.setTextSize(25);
        Button CompleteRegister = (Button) findViewById(R.id.CompleteRegisterBtn);
        final EditText RegisteredUser = (EditText) findViewById(R.id.RegisteredUser);
        final EditText RegisteredPass = (EditText) findViewById(R.id.RegisteredPass);
        final EditText RegisteredName = (EditText) findViewById(R.id.RegisteredFn);
        final EditText RegisteredPhone = (EditText) findViewById(R.id.RegisteredPhone);
        final EditText RegisteredID = (EditText) findViewById(R.id.RegisteredID);

        CompleteRegister.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                final String User2String = String.valueOf(RegisteredUser.getText());
                final String Pass2String = String.valueOf(RegisteredPass.getText());
                final String Name2String = String.valueOf(RegisteredName.getText());
                final String Phone2String = String.valueOf(RegisteredPhone.getText());
                 String ID2String = String.valueOf(RegisteredID.getText());
                if (User2String.equals("") || Pass2String.equals("") || Name2String.equals("") || Phone2String.equals("") || ID2String.equals("")) {
                    Toast.makeText(RegisterActivity.this, "!!!", Toast.LENGTH_SHORT).show();
                }
                else {

                    UserTable NewUser = new UserTable(User2String, Pass2String, Name2String, Phone2String, ID2String);
                    db.Add(NewUser);
                    Toast.makeText(RegisterActivity.this, "!", Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(RegisterActivity.this, LoginActivity.class));
                }
            }
        });
    }
}

更新：

package com.example.nir.nestleapp;


import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import java.util.HashMap;

public class MyDBHandler extends SQLiteOpenHelper {
    public static final int DATABASE_VERSION = 3;
    public static final String DATABASE_NAME = "UsersTable.db";
    public static final String Table_Name = "UsersTable";
    public static final String KEY_ID="ID";
    public static final String KEY_User = "User";
    public static final String KEY_Password = "Password";
    public static final String KEY_FullName = "FullName";
    public static final String KEY_PhoneNumber="PhoneNumber";
    public static final String KEY_IDNUMBER="IDNumber";
    public static final String[] DB_COL=new String[]{KEY_User, KEY_Password, KEY_FullName, KEY_PhoneNumber, KEY_IDNUMBER};

    public MyDBHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String CreateTableSql = "Create Table " + Table_Name + " ( " +
                KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT , " +
                KEY_User + " TEXT , " +
                KEY_Password + " TEXT , " +
                KEY_FullName + " TEXT , "+
                KEY_PhoneNumber+" TEXT , "+
                KEY_IDNUMBER+ " ) ";
        db.execSQL(CreateTableSql);
    }@Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + Table_Name);
        onCreate(db);
    }
    public void Add(UserTable NewUser) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(KEY_User,NewUser.GetUserName() );
        values.put(KEY_Password, NewUser.GetPassword());
        values.put(KEY_FullName,NewUser.GetFullName());
        values.put(KEY_PhoneNumber,NewUser.GetPhoneNumber());
        values.put(KEY_IDNUMBER,NewUser.GetID());
        db.insert(Table_Name, null, values);
        db.close();
    }
}

Answer 1

Key_User字段为integer和autoincrement。您可以在String方法中将Add插入其中。您不应为此字段插入任何记录。数据库将管理此字段。你应该尝试以下方法。

 public void addUser(UserTable NewUser) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(KEY_Password, NewUser.getPassword());
        values.put(KEY_FullName,NewUser.getFullName());
        values.put(KEY_PhoneNumber,NewUser.getPhoneNumber());
        values.put(KEY_IDNUMBER,NewUser.getId());
        db.insert(Table_Name, null, values);
        db.close();
    }

数据库一直说它没有物品

1 个答案: