为什么我的插入查询不起作用..？

Question

我是 Android 的新手。我想在此过程中将数据存储在 Android SQLite 中，我正在插入一些值，但它们没有插入。我在哪里做错了。我没有得到解决方案，请帮助我。

Mainacticity.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingLeft="10sp"
    android:paddingRight="10sp"
    tools:context="com.example.admin.justtrail.MainActivity">
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="user name"
        android:gravity="center"
        android:id="@+id/loginusernameid"
        android:layout_marginTop="10sp"
        />
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="password"
        android:gravity="center"
        android:id="@+id/loginpasswordid"
        android:layout_marginTop="10sp"
        />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="login"
        android:onClick="logIn"
        android:id="@+id/logid"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="signup"
        android:id="@+id/signupid"
        android:onClick="signup"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="select"
        android:text="select"/>
</LinearLayout>

MainActivity.java:

package com.example.admin.justtrail;

import android.content.DialogInterface;
import android.content.Intent;
import android.os.AsyncTask;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

import java.io.File;

public class MainActivity extends AppCompatActivity {
    DatabaseHandler databaseHandler=new DatabaseHandler(MainActivity.this);
    EditText loginusername,loginpassword;
    String data;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        loginpassword = (EditText)findViewById(R.id.loginpasswordid);
        loginusername = (EditText)findViewById(R.id.loginusernameid);

    }

    public void logIn(View view)
    {
        String logusername=loginusername.getText().toString();
        String logpassword=loginpassword.getText().toString();
       // Object usernaeme;
        String data = databaseHandler.check(logusername,logpassword);
        Log.v("sdfsdfsf",data);
    }

    public void signup(View  view)
    {
      // String DATABASE_NAME="Chandu";
       // String TABLE_NAME="fbdatabase";
        Intent intent=new Intent(getApplicationContext(),Signup.class);
        startActivity(intent);
       /* File file = new File(String.valueOf(getDatabasePath(TABLE_NAME)));
        boolean bb =file.isFile();

        if(bb ==true)
        {

            Toast.makeText(getApplicationContext(),"table is created",Toast.LENGTH_LONG).show();
        }
        else
        {
            Toast.makeText(getApplicationContext(),"table is not created",Toast.LENGTH_LONG).show();

        }*/
    }

    public void select(View view)
    {
        final AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
        alertDialogBuilder.setMessage("Are you sure you want see data?");

        alertDialogBuilder.setPositiveButton("Yes", new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface arg0, int arg1) {
                data= databaseHandler.seclctquery();
                Data da = new Data();

                gotosecond();
           }
        });
        alertDialogBuilder.show();
    }

    private void gotosecond() 
    {
        final AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
        alertDialogBuilder.setMessage(data);
        alertDialogBuilder.show();
    }
}

signup.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.admin.justtrail.Signup">
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Name"
        android:gravity="center"
        android:id="@+id/nameid"
        />
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="User Name"
        android:gravity="center"
        android:id="@+id/signupusernameid"
        android:layout_marginTop="40sp"/>
    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Password"
        android:id="@+id/singuppasswordid"
        android:layout_marginTop="80sp"
        android:inputType="textPassword"
        android:gravity="center"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Submit"
        android:id="@+id/signupsubmitid"
        android:layout_marginTop="120sp"/>

</RelativeLayout>

Signup.java:

package com.example.admin.justtrail;

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.Toast;

public class Signup extends AppCompatActivity {
    EditText ename,eusername,epassword;
    DatabaseHandler databaseHandler=new DatabaseHandler(Signup.this);
    Button subbutton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_signup);
        ename=(EditText)findViewById(R.id.nameid);
        eusername=(EditText)findViewById(R.id.signupusernameid);
        epassword=(EditText)findViewById(R.id.singuppasswordid);
        subbutton=(Button)findViewById(R.id.signupsubmitid);
        subbutton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String Name=ename.getText().toString();
                String Username=eusername.getText().toString();
                String Password=epassword.getText().toString();
                Data da=new Data();
                da.setName(Name);
                da.setUsername(Username);
                da.setPassword(Password);
                databaseHandler.addPersion(Name,Username,Password);
                ename.setText("");
                eusername.setText("");
                epassword.setText("");
                Toast.makeText(getApplicationContext(),"sign up success",Toast.LENGTH_LONG).show();
            }
        });
    }
}

Data.java:

package com.example.admin.justtrail;

/**
 * Created by admin on 9/16/2016.
 */
public class Data {
   // Data da=new Data();
    String Name;
    String Username;
    String Password;


    public String getName() {
        return Name;
    }

    public String getUsername() {
        return Username;
    }
    public  String getPassword() {
        return Password;
    }

    public void setName(String name) {
        Name = name;
    }

    public void setUsername(String username) {
        Username = username;
    }
    public void setPassword(String password){
        Password=password;
    }


}

DatabaseHelper.java:

package com.example.admin.justtrail;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
/**
 * Created by admin on 9/15/2016.
 */
 public class DatabaseHandler extends SQLiteOpenHelper {
   private static final String DATABASE_NAME="Chandu";
   private static final int DATABASE_VERSION=1;
   private static final String TABLE_NAME="fbdatabase";
   private static final String ID="ID";
   private static final String NAME="NAME";
   private static final String USER_NAME="USER_NAME";
   private static final String PASSWORD="PASSWORD";

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

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
       String query = "CREATE TABLE"+" "+ TABLE_NAME +"("+ID +" INTEGER PRIMARY KEY AUTOINCREMENT,"+NAME +"TEXT,"+USER_NAME +"TEXT,"+PASSWORD +"VARCHAR"+");";
       Log.v("sdfsdf", query);
       sqLiteDatabase.execSQL(query);

    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int oldVersion, int newVersion) {
        sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
        // Create tables again
        onCreate(sqLiteDatabase);
    }

    public void addPersion(String name,String user_name,String password)
    {
        SQLiteDatabase sqLiteDatabase=this.getWritableDatabase();
        ContentValues values=new ContentValues();
        values.put(NAME,name);
        values.put(USER_NAME,user_name);
        values.put(PASSWORD,password);
        sqLiteDatabase.insert(TABLE_NAME,null,values);
        sqLiteDatabase.close();
    }

    public String check(String USER_NAME,String PASSWORD)
    {
        SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();

        //String seclectquery = "SELECT "+USER_NAME +","+PASSWORD +" FROM"+" "+TABLE_NAME+";";
        //Select * from database where username = '+USER_NAME+',password ='+PASSWORD+';
        String seclectquery = "SELECT * FROM "+TABLE_NAME+" WHERE username="+USER_NAME+",password="+PASSWORD+";";
        sqLiteDatabase.execSQL(seclectquery);
        return seclectquery;
    }

    public String selectquery ( ) {
        SQLiteDatabase sqLiteDatabase = this.getWritableDatabase();
        String query1 = "SELECT * FROM"+" "+TABLE_NAME;
        // sqLiteDatabase.execSQL(query1);
        Cursor cursor = sqLiteDatabase.rawQuery(query1, null);
        String line="";
        int i =0;
        if(cursor.moveToFirst())
        {


            do {
                String s1 = cursor.getString(0);
                String s2 = cursor.getString(1);
                String s3 = cursor.getString(2);
                String s4 = cursor.getString(3);

                Log.v("asdasdadasdas",s1);
                Log.v("asdasdadasdas",s2);
                Log.v("asdasdadasdas",s3);
                Log.v("asdasdadasdas",s4);
                line = line+s1 + s2 + s3 + s4+"\n";
            }
            while (cursor.moveToNext());
        }

        return line;

    }


}

Answer 1

第一个问题 到目前为止我遇到的是在创建 table 时列名和数据类型之间缺少 space。

改变这个

String query = "CREATE TABLE"+" "+ TABLE_NAME +"("+ID +" INTEGER PRIMARY KEY AUTOINCREMENT,"+NAME +"TEXT,"+USER_NAME +"TEXT,"+PASSWORD +"VARCHAR"+");";

到

String query = "CREATE TABLE"+" "+ TABLE_NAME +"("+ID +" INTEGER PRIMARY KEY AUTOINCREMENT,"+NAME +" TEXT,"+USER_NAME +" TEXT,"+PASSWORD +" VARCHAR"+");";

为什么我的插入查询不起作用..？

Why my insert query is not working ..?

android

android-sqlite

android-sql