java编程语言和android开发

Question

good evening dear friends, I'm working with SQLite db and android android applications I have a problem with my button when I click on login activity the message "could not execute for android onClick" my code are:

for LoginDatabaseAdapter.java class:

   package com.delaroystudios.bus_seat_booking_system;

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

/**
 * Created by mugenzi israel on 9/19/2017.
 */

    public class LoginDataBaseAdapter {
        static final String DATABASE_NAME = "login.db";
        static final int DATABASE_VERSION = 1;
        static final String TABLE_NAME ="LOGIN";
        public static final int NAME_COLUMN = 1;
         static final String DATABASE_CREATE = "CREATE TABLE" + TABLE_NAME + "(" + " ID " + " INTEGER PRIMARY KEY AUTOINCREMENT," + " USERNAME text, PASSWORD text );";
    public SQLiteDatabase db;
    private Context context ;
    private DataBaseHelper dbHelper;
    public LoginDataBaseAdapter(Context _context){
        Context context;
        context = _context;
        dbHelper = new DataBaseHelper(context,DATABASE_NAME,null,DATABASE_VERSION);
    }
  public LoginDataBaseAdapter open() throws SQLException{
      db = dbHelper.getWritableDatabase();
      return this;
  }
  public void close(){
      db.close();
  }
  public SQLiteDatabase getDatabaseInstance(){

      return db;
  }
  public  void insertEntry(String userName,String password){
      ContentValues newValues = new ContentValues();
      newValues.put("USERNAME",userName);
      newValues.put("PASSWORD",password);
      db.insert("LOGIN",null,newValues);
  }
  public int deleteEntry(String UserName){
      String where = "USERNAME=?";
      int numberOFEntriesDeleted;
      numberOFEntriesDeleted = db.delete(
              "LOGIN",where, new String[]{
                      UserName}
      );
      return numberOFEntriesDeleted;
  }

  public String getSingleEntry(String userName){
     Cursor cursor = db.query("LOGIN",null,"USERNAME=?",new  String[]{userName},null,null,null);
      if(cursor.getCount()<1){
          cursor.close();
          return "NOT EXIST";
      }
      cursor.moveToFirst();
      String password = cursor.getString(cursor.getColumnIndex("PASSWORD"));
      cursor.close();
      return password;
  }
  public void updateEntry(String userName,String password){
      ContentValues updatedValues = new ContentValues();
      updatedValues.put("USERNAME",userName);
      updatedValues.put("PASSWORD",password);
      String where = "USERNAME = ?";
      db.update("LOGIN",updatedValues,where,new String[]{userName});
  }
}

code for DatabaseHelper.java class:

package com.delaroystudios.bus_seat_booking_system;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

/**
 * Created by mugenzi israel on 9/19/2017.
 */

public class DataBaseHelper extends SQLiteOpenHelper {
  public DataBaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){
      super(context,name,factory,version);
  }

    private static final String TABLE_NAME = "LOGIN";
    static final String DATABASE_CREATE = "CREATE TABLE" + TABLE_NAME + "(" + " ID " + " INTEGER PRIMARY KEY AUTOINCREMENT," + " USERNAME text, PASSWORD text );";
  @Override
    public void onCreate(SQLiteDatabase _db){
     _db.execSQL(LoginDataBaseAdapter.DATABASE_CREATE);
  }
  @Override
    public void onUpgrade(SQLiteDatabase _db,int _oldVersion,int _newVersion){
     Log.w("TaskDBAdapter","Upgrading from version"+_oldVersion+"to"+_newVersion+
             ",which will destroy all old data") ;
      _db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
      onCreate(_db);
  }
}

code for Main_activity_login.java class:

package com.delaroystudios.bus_seat_booking_system;
import android.app.Dialog;
import android.content.Intent;
import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.SpinnerAdapter;
import android.widget.TextView;
import android.widget.Toast;


public class Main_activity_login extends AppCompatActivity {
    Button login;
    Button sign;
    LoginDataBaseAdapter loginDataBaseAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_login);
       /* final Button login;
        final Button sign;
        LoginDataBaseAdapter loginDataBaseAdapter;*/
        login = (Button)findViewById(R.id.log);
        final Spinner spinner = (Spinner)findViewById(R.id.spinner1);
         sign = (Button)findViewById(R.id.sgn);
       loginDataBaseAdapter = new LoginDataBaseAdapter(this);
        loginDataBaseAdapter = loginDataBaseAdapter.open();
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,R.array.roles_selection,android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
       spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long l) {
                Toast.makeText(getBaseContext(),parent.getItemAtPosition(position)+ "Selected",Toast.LENGTH_LONG).show();
                ((TextView) parent.getChildAt(0)).setTextColor(Color.RED);//TO change the color of spinner items

              final Intent intent;
                switch (position)
                {
                    case 1:
                        intent = new Intent(Main_activity_login.this,Bus_info_admin.class);
                        startActivity(intent);
                        break;
                    case 2:
                        intent = new Intent(Main_activity_login.this,pick_ticket.class);
                        startActivity(intent);
                        break;
                    case 3:
                        intent = new Intent(Main_activity_login.this,SignIn.class);
                        startActivity(intent);
                        break;
                    case 4:
                        intent = new Intent(Main_activity_login.this,View_Booking.class);
                        startActivity(intent);
                    default:
                        System.out.println("wrong");
                }
                 }

            @Override
            public void onNothingSelected(AdapterView<?> parent){

            }
        });

       /* login.setOnClickListener(
                new View.OnClickListener(){
                    @Override
                    public void onClick(View v) {
                        // code for button one click
                        Intent intent = new Intent(Main_activity_login.this,DetailsLogin.class);                          startActivity(intent);

                    }

                }
        );*/
   sign.setOnClickListener(
   new View.OnClickListener(){
    @Override
   public void onClick(View view){
        Intent intent = new Intent(Main_activity_login.this,SignIn.class);
        startActivity(intent);
    }
   }
   );

    }
public void logIn(View v){
    final Dialog dialog = new Dialog(Main_activity_login.this);
    dialog.setContentView(R.layout.activity_main_login);//
    dialog.setTitle("Login");
    final EditText editUserName = (EditText)findViewById(R.id.EditLog);
    final EditText editPassword = (EditText)findViewById(R.id.Edit_menu2);
    Button btnLogin = (Button)findViewById(R.id.log);

    final String userName,password,storedPassword;

    userName = editUserName.getText().toString();
    password = editPassword.getText().toString();
    storedPassword = loginDataBaseAdapter.getSingleEntry(userName);
     btnLogin.setOnClickListener(
            new View.OnClickListener(){
          public void onClick(View v){

              if (password.equals(storedPassword)){
                  Toast.makeText(Main_activity_login.this,"You made it!,Login successful",Toast.LENGTH_LONG).show();
                  dialog.dismiss();
                  Intent intent = new Intent(Main_activity_login.this,DetailsLogin.class);
                  startActivity(intent);
              }
              else {
                  Toast.makeText(Main_activity_login.this,"User name or password does not match",Toast.LENGTH_LONG).show();
              }
          }
            }
    );

}
    @Override
    protected  void onDestroy(){
        super.onDestroy();
        loginDataBaseAdapter.close();
    }

    /*public void startActivity() {
        Intent intent = new Intent(Main_activity_login.this,Bus_info_admin.class);
        startActivity(intent);
    }*/
 /*public void buttonLoginClick(View v){

        Intent intent = new Intent(v.getContext(),DetailsLogin.class);
        v.getContext().startActivity(intent);

    }

    */

    }

code for SignIn.java:

 package com.delaroystudios.bus_seat_booking_system;

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

    public class SignIn extends AppCompatActivity {  //AppCompatActivity
        EditText editUserName,editPassword,editConfirmPassword;
        Button btnCreateAccount,btn;
        Context context = this;
        LoginDataBaseAdapter loginDataBaseAdapter;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_sign_in);

    loginDataBaseAdapter = new LoginDataBaseAdapter(this);
     loginDataBaseAdapter = loginDataBaseAdapter.open();
     editUserName =(EditText)findViewById(R.id.id_name);
     editPassword = (EditText)findViewById(R.id.email);
            editConfirmPassword = (EditText)findViewById(R.id.password);
            btnCreateAccount = (Button)findViewById(R.id.register) ;

            btnCreateAccount.setOnClickListener(
                    new View.OnClickListener(){
          public  void onClick(View v){
         String userName = editUserName.getText().toString();
         String password = editPassword.getText().toString();
         String confirmPassword = editConfirmPassword.getText().toString();

         if (userName.equals("")||password.equals("")||confirmPassword.equals("")){
             Toast.makeText(getApplicationContext(),"Field Vacant",Toast.LENGTH_LONG).show();
    return;
         }
         if (!password.equals(confirmPassword)){
        Toast.makeText(getApplicationContext(),"Password does not match",Toast.LENGTH_LONG).show();
         return;
         }
         else {
     loginDataBaseAdapter.insertEntry(userName,password);
     Toast.makeText(getApplicationContext(),"Account Successfully created",Toast.LENGTH_LONG).show();
         Intent i = new Intent(SignIn.this,Main_activity_login.class);
             startActivity(i);
             finish();
         }
          }
      }
            );

       /*btn.setOnClickListener(
       new View.OnClickListener(){
       @Override
      public void onClick(View view){
           Intent intent = new Intent(SignIn.this,Main_activity_login.class);
           startActivity(intent);
       }
       );*/


        }
        @Override
        protected void onDestroy(){
            super.onDestroy();
            loginDataBaseAdapter.close();
        }

    }

code for sign_in.xml:

   <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.delaroystudios.bus_seat_booking_system.SignIn">
<TextView
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:text="@string/register_here"
    android:textSize="32sp"
    android:gravity="center"
android:layout_marginTop="30dp"
    />
 <EditText
     android:layout_marginTop="40dp"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:hint="@string/user_id"
     android:id="@+id/id_user"

     />
    <EditText
        android:layout_marginTop="30dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/full_name"
        android:id="@+id/id_name"


        />
    <EditText
        android:layout_marginTop="30dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/phone_no"
        android:id="@+id/phone"


        />

    <EditText
        android:id="@+id/email"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp"
        android:hint="@string/email_id"
         />

    <EditText
        android:layout_marginTop="30dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/password"
        android:id="@+id/password"
        android:layout_marginBottom="20dp"
        />

    <Button

        android:id="@+id/register"
        android:layout_width="150dp"
        android:layout_height="50dp"
        android:layout_gravity="center"
        android:text="@string/register"
        android:onClick="onClick"
        />
</LinearLayout>

code for activity_main_login.xml:

 <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal"
    tools:context="com.delaroystudios.bus_seat_booking_system.Main_activity_login"
android:background="@drawable/bus1"
    >

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:id="@+id/menu1"
        android:layout_marginBottom="100dp"
        android:layout_marginTop="20dp"
        android:gravity="center"
        android:layout_marginStart="30dp"
        >
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home"
            android:textSize="20sp"
            android:textColor="#9b59b6"
            />

        <Button
            android:id="@+id/textView2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/about"
            android:textColor="#9b59b6"
            android:textSize="20sp" />

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/contact"
            android:textSize="20sp"
            android:textColor="#9b59b6"
            />
       <!--a verifier -->

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_below="@+id/menu1"
        android:id="@+id/menu2"
        android:layout_marginBottom="30dp"
        >
  <TextView
      android:layout_width="150dp"
      android:layout_height="wrap_content"
      android:text="@string/Login2"
      android:textSize="28sp"
android:textColor="#9b59b6"
      />

        <EditText
            android:id="@+id/EditLog"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="@string/login"
            android:textColorHint="#9b59b6"
            android:textColor="#ffffff"
            />
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_below="@+id/menu2"
        android:id="@+id/menu3"
        android:layout_marginBottom="30dp"
        >

        <TextView
            android:id="@+id/textView"
            android:layout_width="150dp"
            android:layout_height="wrap_content"
            android:text="@string/Pass"
            android:textSize="28sp"
            android:textColor="#9b59b6"
            />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="@string/your_password"
            android:id="@+id/Edit_menu2"
            android:textColorHint="#9b59b6"
            android:textColor="#ffffff"
            />
    </LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_below="@+id/menu3"
        android:layout_marginBottom="10dp"
        android:id="@+id/role"
        >
        <TextView
            android:id="@+id/T_role"
            android:layout_width="150dp"
            android:layout_height="wrap_content"
            android:text="@string/role"
            android:textSize="28sp"
            android:textColor="#9b59b6"
            />
<Spinner
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:id="@+id/spinner1"

    />
    </LinearLayout>
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:id="@+id/men1"
        android:layout_marginTop="70dp"
        android:layout_below="@+id/role"
        android:gravity="center"
        android:layout_marginStart="30dp"
        >
    <Button
        android:id="@+id/log"
        android:layout_width="150dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="30dp"
        android:onClick="logIn"
        android:text="@string/login"
        android:textColor="#9b59b6"
        android:textColorHint="#9b59b6"
        android:textSize="20sp"

        />
   <Button
        android:id="@+id/sgn"
        android:layout_width="150dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="30dp"
        android:onClick="onClick"
        android:text="@string/sign_in"
        android:textColor="#9b59b6"
        android:textColorHint="#9b59b6"
        android:textSize="20sp"

       />

Answer 1

In sign_in.xml ,

<Button
    android:id="@+id/register"
    android:layout_width="150dp"
    android:layout_height="50dp"
    android:layout_gravity="center"
    android:text="@string/register"
    android:onClick="onClick"
    />

remove android:onClick="onClick" line. That should be work.