i'm working on a project bus routes and i need help with the debugging part. my tables are not created in the databases and i'm having problems like when my icon is clicked it says "unfortunately the app is stopped"....pls help me.... Thanks in advance!!\[code\]myactivity.java public class MainActivity extends Activity { SQLiteDatabase db; DbHelper dbHelper; Button route; protected String[] columns; String[] strings = { "TAMBARAM", "PERUNGULATHUR", "VANDALUR", "URAPAKKAM", "GUDUVANCHERI", "POTHERI", "KATTANKULATHUR", "M.M.NAGAR", "CHENGALPET", }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); db = dbHelper.getReadableDatabase(); try { } catch(SQLException e) { e.getMessage(); } route = (Button) findViewById(R.id.route); try { } catch (SQLException e) { e.printStackTrace(); } route.setOnClickListener(new OnClickListener() { public void onClick(View v) { Cursor cursor = db.rawQuery("select busno from bus_detail);", null); if(cursor !=null && cursor.moveToFirst()) { TextView places = (TextView) findViewById(R.id.show); places.setText(cursor.getString(2)); } } }); db.close(); ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_dropdown_item_1line,strings); AutoCompleteTextView source = (AutoCompleteTextView)findViewById(R.id.source); AutoCompleteTextView destination = (AutoCompleteTextView)findViewById(R.id.dest); source.setThreshold(1); source.setAdapter(adapter); destination.setThreshold(1); destination.setAdapter(adapter); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; }} \[/code\]\[code\]databasehelper.javapublic class DbHelper extends SQLiteOpenHelper { // Database Name private static final String DATABASE_NAME = "bus_routes.db"; private static final int DATABASE_VERSION = 1; // table names private static final String BUS_MASTER = "bus_master"; private static final String BUS_DETAIL = "bus_detail"; // Columns names private static final String BUS_NO = "bus_no"; private static final String SOURCE = "source"; private static final String DESTINATION = "destination"; private static final String PLACE = "place"; private static final String ARRIVAL_TIME = "arrival_time"; public DbHelper(Context context) { super(context,DATABASE_NAME, null, DATABASE_VERSION); // TODO Auto-generated constructor stub } @Override public void onCreate(SQLiteDatabase db) { // TODO Auto-generated method stub String CREATE_BUS_MASTER = "CREATE TABLE " + BUS_MASTER + "(" + BUS_NO + " INTEGER PRIMARY KEY," + SOURCE+ " TEXT," + DESTINATION + " TEXT" + ")"; String CREATE_BUS_DETAIL = "CREATE TABLE " + BUS_DETAIL + "(" + BUS_NO + " INTEGER FOREIGN KEY REFERNCES BUS_MASTER(BUS_NO)," + PLACE+ " TEXT," + ARRIVAL_TIME+ " TEXT" + ")"; db.execSQL(CREATE_BUS_MASTER); db.execSQL(CREATE_BUS_DETAIL); } public void onOpen(SQLiteDatabase DB) { onOpen(DB); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO Auto-generated method stub db.execSQL("DROP TABLE IF EXISTS " + BUS_MASTER); db.execSQL("DROP TABLE IF EXISTS " + BUS_DETAIL); // Create tables again onCreate(db); } public void addBus(int bus_no, String source, String destination) { // TODO Auto-generated method stub SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put("busno",BUS_NO); values.put("source",SOURCE); // source values.put("destination",DESTINATION); // destination // Inserting Row db.insert(BUS_MASTER, null, values); } public void addBus_detail(int bus_no, String place, String arrival_time) { // TODO Auto-generated method stub SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put("busno",BUS_NO); values.put("place",PLACE); values.put("arrival_time",ARRIVAL_TIME); db.insert(BUS_DETAIL, null, values); } }\[/code\]\[code\]xml file<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="wrap_content" android:layout_height="match_parent" android:gravity="top" android
addingBottom="@dimen/activity_vertical_margin" androidaddingLeft="@dimen/activity_horizontal_margin" androidaddingRight="@dimen/activity_horizontal_margin" androidaddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity" > <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:layout_marginTop="57dp" android:text="@string/source" android:textAppearance="?android:attr/textAppearanceMedium" /> <AutoCompleteTextView android:id="@+id/actvDev" android:layout_width="150dp" android:layout_height="wrap_content" android:layout_alignBottom="@+id/textView1" android:layout_alignRight="@+id/actDevd" android:layout_toRightOf="@+id/textView2" android:ems="10" android:labelFor="2" android:text="@string/s" /> <requestFocus /> <AutoCompleteTextView android:id="@+id/actDevd" android:layout_width="150dp" android:layout_height="wrap_content" android:layout_alignBottom="@+id/textView2" android:layout_alignLeft="@+id/button1" android:layout_alignParentRight="true" android:layout_marginRight="16dp" android:ems="10" android:text="@string/d" /> <Button android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_below="@+id/textView2" android:layout_marginTop="26dp" android:layout_toRightOf="@+id/textView2" android:text="@string/routes" /> <TextView android:id="@+id/textView3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/textView2" android:layout_alignParentBottom="true" android:layout_alignRight="@+id/actDevd" android:layout_below="@+id/button1" android:layout_marginTop="81dp" android:text="@string/disp" android:textAppearance="?android:attr/textAppearanceMedium" /> <TextView android:id="@+id/textView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_below="@+id/textView1" android:layout_marginTop="44dp" android:text="@string/dest" android:textAppearance="?android:attr/textAppearanceMedium" /></RelativeLayout>\[/code\]\[code\]04-04 14:14:43.700: D/AndroidRuntime(868): Shutting down VM04-04 14:14:43.700: W/dalvikvm(868): threadid=1: thread exiting with uncaught exception (group=0x40a71930)04-04 14:14:43.720: E/AndroidRuntime(868): FATAL EXCEPTION: main04-04 14:14:43.720: E/AndroidRuntime(868): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.bus/com.example.bus.MainActivity}: java.lang.NullPointerException04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.access$600(ActivityThread.java:141)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)04-04 14:14:43.720: E/AndroidRuntime(868): at android.os.Handler.dispatchMessage(Handler.java:99)04-04 14:14:43.720: E/AndroidRuntime(868): at android.os.Looper.loop(Looper.java:137)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.main(ActivityThread.java:5041)04-04 14:14:43.720: E/AndroidRuntime(868): at java.lang.reflect.Method.invokeNative(Native Method)04-04 14:14:43.720: E/AndroidRuntime(868): at java.lang.reflect.Method.invoke(Method.java:511)04-04 14:14:43.720: E/AndroidRuntime(868): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)04-04 14:14:43.720: E/AndroidRuntime(868): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)04-04 14:14:43.720: E/AndroidRuntime(868): at dalvik.system.NativeStart.main(Native Method)04-04 14:14:43.720: E/AndroidRuntime(868): Caused by: java.lang.NullPointerException04-04 14:14:43.720: E/AndroidRuntime(868): at com.example.bus.MainActivity.onCreate(MainActivity.java:44)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.Activity.performCreate(Activity.java:5104)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)04-04 14:14:43.720: E/AndroidRuntime(868): ... 11 more\[/code\]
addingBottom="@dimen/activity_vertical_margin" androidaddingLeft="@dimen/activity_horizontal_margin" androidaddingRight="@dimen/activity_horizontal_margin" androidaddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity" > <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:layout_marginTop="57dp" android:text="@string/source" android:textAppearance="?android:attr/textAppearanceMedium" /> <AutoCompleteTextView android:id="@+id/actvDev" android:layout_width="150dp" android:layout_height="wrap_content" android:layout_alignBottom="@+id/textView1" android:layout_alignRight="@+id/actDevd" android:layout_toRightOf="@+id/textView2" android:ems="10" android:labelFor="2" android:text="@string/s" /> <requestFocus /> <AutoCompleteTextView android:id="@+id/actDevd" android:layout_width="150dp" android:layout_height="wrap_content" android:layout_alignBottom="@+id/textView2" android:layout_alignLeft="@+id/button1" android:layout_alignParentRight="true" android:layout_marginRight="16dp" android:ems="10" android:text="@string/d" /> <Button android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_below="@+id/textView2" android:layout_marginTop="26dp" android:layout_toRightOf="@+id/textView2" android:text="@string/routes" /> <TextView android:id="@+id/textView3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/textView2" android:layout_alignParentBottom="true" android:layout_alignRight="@+id/actDevd" android:layout_below="@+id/button1" android:layout_marginTop="81dp" android:text="@string/disp" android:textAppearance="?android:attr/textAppearanceMedium" /> <TextView android:id="@+id/textView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_below="@+id/textView1" android:layout_marginTop="44dp" android:text="@string/dest" android:textAppearance="?android:attr/textAppearanceMedium" /></RelativeLayout>\[/code\]\[code\]04-04 14:14:43.700: D/AndroidRuntime(868): Shutting down VM04-04 14:14:43.700: W/dalvikvm(868): threadid=1: thread exiting with uncaught exception (group=0x40a71930)04-04 14:14:43.720: E/AndroidRuntime(868): FATAL EXCEPTION: main04-04 14:14:43.720: E/AndroidRuntime(868): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.bus/com.example.bus.MainActivity}: java.lang.NullPointerException04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.access$600(ActivityThread.java:141)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)04-04 14:14:43.720: E/AndroidRuntime(868): at android.os.Handler.dispatchMessage(Handler.java:99)04-04 14:14:43.720: E/AndroidRuntime(868): at android.os.Looper.loop(Looper.java:137)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.main(ActivityThread.java:5041)04-04 14:14:43.720: E/AndroidRuntime(868): at java.lang.reflect.Method.invokeNative(Native Method)04-04 14:14:43.720: E/AndroidRuntime(868): at java.lang.reflect.Method.invoke(Method.java:511)04-04 14:14:43.720: E/AndroidRuntime(868): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)04-04 14:14:43.720: E/AndroidRuntime(868): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)04-04 14:14:43.720: E/AndroidRuntime(868): at dalvik.system.NativeStart.main(Native Method)04-04 14:14:43.720: E/AndroidRuntime(868): Caused by: java.lang.NullPointerException04-04 14:14:43.720: E/AndroidRuntime(868): at com.example.bus.MainActivity.onCreate(MainActivity.java:44)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.Activity.performCreate(Activity.java:5104)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)04-04 14:14:43.720: E/AndroidRuntime(868): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)04-04 14:14:43.720: E/AndroidRuntime(868): ... 11 more\[/code\]