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POunable to retrieve data from sqlite database
 

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    <p>In this app I want that as I click on button the data from my database display on List View and by using OnItemClick() it should show another activity But Unfortunately my application is is being stopped as I click on Button Plzz tell me where m I getting wrong Here is my activity class `</p> <pre><code>public class DictionaryActivity extends Activity { protected EditText searchText; protected DatabaseHelper d; protected Cursor cursor; protected ListAdapter adapter; protected ListView wordList; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); d = new DatabaseHelper(this); d.addWord(new Contact("Apple", "Fruit")); d.addWord(new Contact("Ape", "Animal")); d.addWord(new Contact("Boy", "Male")); d.addWord(new Contact("Bat", "Playing Object")); searchText = (EditText) findViewById(R.id.word); wordList = (ListView) findViewById(R.id.list); final Button button = (Button) findViewById(R.id.search); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub searchword(v); } }); } public void searchword(View view) { // || is the concatenation operation in SQLite cursor = d.getData(searchText); adapter = new SimpleCursorAdapter(this, R.layout.word_list, cursor, new String[] { "word" }, new int[] { R.id.word }); wordList.setAdapter(adapter); wordList.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView&lt;?&gt; parent, View view, int position, long id) { // TODO Auto-generated method stub Intent intent = new Intent(getApplicationContext(), WordDetails.class); Cursor cursor = (Cursor) adapter.getItem(position); intent.putExtra("Word_ID", cursor.getInt(cursor.getColumnIndex("id"))); startActivity(intent); } }); }}` </code></pre> <p>Here is DataBaseHelper Class</p> <pre><code>public class DatabaseHelper extends SQLiteOpenHelper { protected SQLiteDatabase db; private static final int DATABASE_VERSION = 1; // Database Name private static final String DATABASE_NAME = "Word_Meanings"; // Contacts table name private static final String TABLE_NAME = "Meanings"; // Contacts Table Columns names private static final String KEY_ID = "id"; private static final String KEY_WORD = "word"; private static final String KEY_MEAN = "mean"; private Contact contact; public DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } // Creating Tables @Override public void onCreate(SQLiteDatabase db) { String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_NAME + "(" + KEY_ID + " INTEGER PRIMARY KEY," + KEY_WORD + " TEXT," + KEY_MEAN + " TEXT" + ")"; db.execSQL(CREATE_CONTACTS_TABLE); } // Upgrading database @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // Drop older table if existed db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME); // Create tables again onCreate(db); } // Adding new contact void addWord(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_WORD, contact.getword()); // Contact Name values.put(KEY_MEAN, contact.getmean()); // Contact Phone // Inserting Row db.insert(TABLE_NAME, null, values); db.close(); // Closing database connection } // Updating single contact public int updateWord(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_WORD, contact.getword()); values.put(KEY_MEAN, contact.getmean()); // updating row return db.update(TABLE_NAME, values, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) }); } // Deleting single contact public void deleteWord(Contact contact) { this.contact = contact; SQLiteDatabase db = this.getWritableDatabase(); db.delete(TABLE_NAME, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) }); db.close(); } // Getting contacts Count public int getCount() { String countQuery = "SELECT * FROM " + TABLE_NAME; SQLiteDatabase db = this.getReadableDatabase(); Cursor cursor = db.rawQuery(countQuery, null); cursor.close(); // return count return cursor.getCount(); } public Cursor getData(EditText s) { // TODO Auto-generated method stub String sql = "SELECT id, word FROM Meanings WHERE word LIKE ?"; String sqlArgs[] = new String[] { s.getText().toString() + "%" }; Cursor c = db.rawQuery(sql, sqlArgs); return c; }} </code></pre> <p>here is logcat:</p> <pre><code>E/AndroidRuntime(543): FATAL EXCEPTION: main E/AndroidRuntime(543): java.lang.NullPointerException E/AndroidRuntime(543): at com.Dictionary.DatabaseHelper.getData(DatabaseHelper.java:107) E/AndroidRuntime(543): at com.Dictionary.DictionaryActivity.searchword(DictionaryActivity.java:56) E/AndroidRuntime(543): at com.Dictionary.DictionaryActivity$1.onClick(DictionaryActivity.java:47) E/AndroidRuntime(543): at android.view.View.performClick(View.java:3511) E/AndroidRuntime(543): at android.view.View$PerformClick.run(View.java:14105) E/AndroidRuntime(543): at android.os.Handler.handleCallback(Handler.java:605) E/AndroidRuntime(543): at android.os.Handler.dispatchMessage(Handler.java:92) E/AndroidRuntime(543): at android.os.Looper.loop(Looper.java:137) E/AndroidRuntime(543): at android.app.ActivityThread.main(ActivityThread.java:4424) E/AndroidRuntime(543): at java.lang.reflect.Method.invokeNative(Native Method) E/AndroidRuntime(543): at java.lang.reflect.Method.invoke(Method.java:511) E/AndroidRuntime(543): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) E/AndroidRuntime(543): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) E/AndroidRuntime(543): at dalvik.system.NativeStart.main(Native Method) </code></pre>
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    1. USswati sinha
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    1. CO"my application is is being stopped as I click on Button" If your app crashes, **always** post the LogCat errors in your question. Otherwise we just have to guess...
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    2. CO@Sam i have posted the LogCat
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    3. COGreat! The first two line of the logcat tell us that in at DatabaseHelper.getData() on line 107 you are trying to reference a method of a null variable. Please post your getData() from DatabaseHelper and mark whichever line is 107.
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