Android-使用预加载的数据库填充Listview

Question

I would like to populate the listview using a preloaded database that I have created using SQLite Database browser. However, I keep getting force close. For the DatabaseHelper class, I followed the tutorial exactly on http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/

Here is my code for displaying the listView:

public class POITab extends ListActivity {
private SQLiteDatabase newDb;
protected Cursor cursor;
protected ListAdapter adapter;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    openDatabase();     
}


private void openDatabase() {
    POIHelper dbHelper = new POIHelper(this.getApplicationContext());
    newDb = dbHelper.getWritableDatabase();
    cursor = newDb.rawQuery("SELECT _id, Name FROM POI", null);
    adapter = new SimpleCursorAdapter(this, R.layout.listitem, cursor, new String[] {"Name"}, new int[] {R.id.name});
    setListAdapter(adapter);
}

@Override
public void onListItemClick(ListView parent, View view, int position, long id) {
      Toast.makeText(getApplicationContext(), ((TextView) view).getText(),
              Toast.LENGTH_SHORT).show();
}

Update: I am not sure but I guess the problem lies with the line

cursor = newDb.rawQuery("SELECT _id, Name FROM POI", null);

this is the code for my databaseHelper class:

public class POIHelper extends SQLiteOpenHelper {

private static String DB_PATH = "/data/data/com.test.mysgapp/databases/";
private static String DB_NAME = "MySgAppdb";
private SQLiteDatabase myDatabase;
private final Context myContext;

public POIHelper(Context context) {
    super(context, DB_NAME, null, 1);
    this.myContext = context;
}

public void createDatabase() throws IOException {
    boolean dbExist = checkDatabase();
    if(dbExist) {

    } else {
        this.getReadableDatabase();
        try {
            copyDatabase();
        } catch (IOException e) {
            throw new Error("Error copying database");
        }
    }
}

private boolean checkDatabase() {
    SQLiteDatabase checkDb = null;

    try {
        String myPath = DB_PATH + DB_NAME;
        checkDb = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
    } catch (SQLiteException e) {
    }

    if(checkDb != null) {
        checkDb.close();
    }
    return checkDb != null ? true : false;
}

private void copyDatabase() throws IOException{
    InputStream input = myContext.getAssets().open(DB_NAME);
    String outFileName = DB_PATH + DB_NAME;
    OutputStream output = new FileOutputStream(outFileName);

    byte[] buffer  = new byte[1024];
    int length;
    while ((length = input.read(buffer))>0) {
        output.write(buffer, 0, length);
    }
    output.flush();
    output.close();
    input.close();
}

public void openDatabase() throws IOException {
    String path = DB_PATH + DB_NAME;
    myDatabase = SQLiteDatabase.openDatabase(path, null, SQLiteDatabase.OPEN_READONLY);
}

@Override
public synchronized void close() {
    if (myDatabase != null)
        myDatabase.close();

    super.close();
}

@Override
public void onCreate(SQLiteDatabase db) {
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}

}

Error Log:

01-10 16:11:52.332: ERROR/AndroidRuntime(1311): FATAL EXCEPTION: main 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.test.mysgapp/com.test.mysgapp.POITab}: android.database.sqlite.SQLiteException: no such table: Places: , while compiling: SELECT _id, Name FROM Places 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.ActivityThread.startActivityNow(ActivityThread.java:2503) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:127) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:339) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:651) 01-10 16:11:52.332: ERROR/An droidRuntime(1311): at android.widget.TabHost.setCurrentTab(TabHost.java:323) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:129) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:453) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.view.View.performClick(View.java:2408) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.view.View$PerformClick.run(View.java:8816) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.os.Handler.handleCallback(Handler.java:587) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.os.Handler.dispatchMessage(Handler.java:92) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.os.Looper.loop(Looper.java:123) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.ActivityThread.main(ActivityThread.java:4627) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at java.lang.reflect.Method.inv okeNative(Native Method) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at java.lang.reflect.Method.invoke(Method.java:521) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at dalvik.system.NativeStart.main(Native Method) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): Caused by: android.database.sqlite.SQLiteException: no such table: Places: , while compiling: SELECT _id, Name FROM Places 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:91) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteCompiledSql.(SQLiteCompiledSql.j ava:64) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteProgram.(SQLiteProgram.java:80) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteQuery.(SQLiteQuery.java:46) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1345) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1315) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at com.test.mysgapp.POITab.openDb(POITab.java:42) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at com.test.mysgapp.POITab.onCreate(POITab.java:36) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 01-10 16:11:52.332: ERROR/AndroidRuntime(131 1): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627) 01-10 16:11:52.332: ERROR/AndroidRuntime(1311): ... 18 more 01-10 16:11:52.392: WARN/ActivityManager(41): Force finishing activity com.test.mysgapp/.MySgApp

Answer 1

I'm guessing but shouldn't setListAdapter(adapter) this be added to a list? like myList.setListAdapter(adapter);

Answer 2

thanks for viewing and helping. I managed to solve the problem. It lies with the database. Something's wrong with the database file. I created a new one and everything works fine now.