Ошибка, но Application Crash

Question

Я новичок в базе данных Android. Я создаю приложение, следуя руководству по youtube о базе данных http://www.youtube.com/watch?v=TApjQ-LFNpI.

Я следил за всем, и, когда я запускал приложение, ошибок не было, но при нажатии кнопки ответа на кнопку создания не было.

вот мой код:

MainActivity.java

package com.example.studentdatabase; 


import android.os.Bundle; 
import android.app.Activity; 
import android.database.Cursor; 
import android.database.sqlite.SQLiteDatabase; 
import android.graphics.Color; 
import android.graphics.Typeface; 
import android.view.View; 
import android.widget.EditText; 
import android.widget.TableLayout; 
import android.widget.TableRow; 
import android.widget.TextView; 

public class MainActivity extends Activity { 
    String fname,lname,email; 
    SQLiteDatabase db; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     db= openOrCreateDatabase("MyDB1",MODE_PRIVATE,null); 
     db.execSQL("CREATE TABLE IF NOT EXISTS Student(fname TEXT,lname TEXT,email TEXT)"); 
    } 

     public void Adddata(View view){ 

     EditText editText1=(EditText) findViewById(R.id.firstname); 
     EditText editText2=(EditText) findViewById(R.id.lastname); 
     EditText editText3=(EditText) findViewById(R.id.email); 

     fname=editText1.getText().toString(); 
     lname=editText2.getText().toString(); 
     email=editText3.getText().toString(); 
     db.execSQL("INSERT INTO Student VALUES('"+fname+"','"+lname+"','"+email+"')"); 


    } 

    public void showdata(View view){ 

     Cursor c=db.rawQuery("SELECT * from Student", null); 
     int count=c.getCount(); 
     c.moveToFirst(); 
     TableLayout tableLayout=new TableLayout(getApplicationContext()); 
     tableLayout.setVerticalScrollBarEnabled(true); 
     TableRow tableRow; 
     TextView textView,textView1,textView2,textView3,textView4,textView5; 
     tableRow=new TableRow(getApplicationContext()); 

     textView=new TextView(getApplicationContext()); 
     textView.setText("Firstname"); 
     textView.setTextColor(Color.RED); 
     textView.setTypeface(null,Typeface.BOLD); 
     textView.setPadding(20, 20, 20, 20); 
     tableRow.addView(textView); 

     textView4=new TextView(getApplicationContext()); 
     textView4.setText("LastName"); 
     textView4.setTextColor(Color.RED); 
     textView4.setTypeface(null,Typeface.BOLD); 
     textView4.setPadding(20, 20, 20, 20); 

     textView5=new TextView(getApplicationContext()); 
     textView5.setText("LastName"); 
     textView5.setTextColor(Color.RED); 
     textView5.setTypeface(null,Typeface.BOLD); 
     textView5.setPadding(20, 20, 20, 20); 
     tableRow.addView(tableRow); 

     for(Integer j=0; j < count; j++){ 
      tableRow=new TableRow(getApplicationContext()); 
      textView1=new TextView(getApplicationContext()); 
      textView1.setText(c.getString(c.getColumnIndex("fname"))); 
      textView2=new TextView(getApplicationContext()); 
      textView2.setText(c.getString(c.getColumnIndex("lname"))); 
      textView3=new TextView(getApplicationContext()); 
      textView3.setText(c.getString(c.getColumnIndex("email"))); 

      textView1.setPadding(20, 20,20, 20); 
      textView2.setPadding(20, 20,20, 20); 
      textView3.setPadding(20, 20,20, 20); 

      tableRow.addView(textView1); 
      tableRow.addView(textView2); 
      tableRow.addView(textView3); 

      tableLayout.addView(tableRow); 
      c.moveToNext(); 




     } 
     setContentView(tableLayout); 
     db.close(); 
     } 
     public void close(View view){ 

      System.exit(0); 
     } 




} 

Activity_main.xml

<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=".MainActivity" > 

    <TextView 
     android:id="@+id/textView1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignLeft="@+id/textView2" 
     android:layout_below="@+id/textView2" 
     android:layout_marginTop="25dp" 
     android:text="last Name" /> 

    <TextView 
     android:id="@+id/textView3" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignLeft="@+id/textView1" 
     android:layout_below="@+id/textView1" 
     android:layout_marginTop="25dp" 
     android:text="Email" /> 

    <TextView 
     android:id="@+id/textView2" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentTop="true" 
     android:layout_marginLeft="18dp" 
     android:layout_marginTop="27dp" 
     android:text="First Name" /> 

    <EditText 
     android:id="@+id/firstname" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignBaseline="@+id/textView2" 
     android:layout_alignBottom="@+id/textView2" 
     android:layout_toRightOf="@+id/textView2" 
     android:ems="10" > 

     <requestFocus /> 
    </EditText> 

    <EditText 
     android:id="@+id/lastname" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignBaseline="@+id/textView1" 
     android:layout_alignBottom="@+id/textView1" 
     android:layout_alignLeft="@+id/firstname" 
     android:ems="10" /> 

    <EditText 
     android:id="@+id/email" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignBaseline="@+id/textView3" 
     android:layout_alignBottom="@+id/textView3" 
     android:layout_toRightOf="@+id/textView1" 
     android:ems="10" /> 

    <Button 
     android:id="@+id/button1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignLeft="@+id/textView3" 
     android:layout_below="@+id/email" 
     android:layout_marginTop="28dp" 
     android:onClick="Adddata" 
     android:text="create" /> 

    <Button 
     android:id="@+id/button2" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignBaseline="@+id/button1" 
     android:layout_alignBottom="@+id/button1" 
     android:layout_alignRight="@+id/email" 
     android:layout_marginRight="42dp" 
     android:onClick="showdata" 
     android:text="Show Table" /> 

    <Button 
     android:id="@+id/button3" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignLeft="@+id/button1" 
     android:layout_below="@+id/button1" 
     android:layout_marginTop="33dp" 
     android:onClick="close" 
     android:text="Close" /> 

</RelativeLayout> 

Answer 1

Я не вижу никакой кнопки или OnClick событие в коде ?! Вы уверены, что настроили событие для своей кнопки?