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androidsqliteandroid-2.2-froyoandroid-2.3-gingerbread

Android SQLite: Loading spinner dynamicaly


I've tried out a couple different ways of loading the spinner from SQLite database, this method seems to be the simplest and easiest. The only thing is since i have added in a couple of my own variables (three more). When I run the edited version to fit my testing needs everything runs correctly except the spinner doesn't fill with data from the database

enter image description here

SpinnerLoad Class

public class SpinnerLoad extends Activity implements OnClickListener {
    private Db thisTestDBAdapter;
    Button save;
    EditText one, two, three;
    Spinner spinner;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.spinnerform);
        save = (Button) findViewById(R.id.spinLoad_save);
        save.setOnClickListener(this);
        one = (EditText) findViewById(R.id.spinLoad_serial);
        two = (EditText) findViewById(R.id.spinLoad_name);
        three = (EditText) findViewById(R.id.spinLoad_place);
        fillData();
        spinner = (Spinner) findViewById(R.id.spinLoad_spinner);
        try {
            spinner.setOnItemSelectedListener(new Person());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static class Person implements OnItemSelectedListener {
        static String personReturn;
        static boolean personTest = false;

        @Override
        public void onItemSelected(AdapterView<?> x, View y, int z, long w) {
            personReturn = (x.getItemAtPosition(z)).toString();
            personTest = true;
        }

        @Override
        public void onNothingSelected(AdapterView<?> arg0) {
            personTest = false;
        }
    }

    private void fillData() {
        try {
            Cursor coloursCursor;
            spinner = (Spinner) findViewById(R.id.spinLoad_spinner);
            coloursCursor = thisTestDBAdapter.fetchAllColours();
            startManagingCursor(coloursCursor);

            String[] from = new String[] { thisTestDBAdapter.KEY_TWO };
            int[] to = new int[] { R.id.tvDBViewRow };

            SimpleCursorAdapter colourAdapter = new SimpleCursorAdapter(this,
                    R.layout.db_view_row, coloursCursor, from, to);

            spinner.setAdapter(colourAdapter);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.spinLoad_save:
            String bx = two.getText().toString();
            /**/
            String ax = one.getText().toString();
            String cx = three.getText().toString();
            String returned = Person.personReturn;

            Db entry = new Db(this);
            entry.open();
            entry.createEntry(ax, bx, cx, returned);
            entry.close();

            fillData();
            /**/
            break;
        }
    }
}

Db SQL helper class

public class Db {

    private static final String TAG = "SpinnerDBHelper";
    private DatabaseHelper mDbHelper;
    private SQLiteDatabase mDb;
    private static final int DATABASE_VERSION = 2;
    private final Context mCtx;
    /**/
    private static final String KEY_DB = "DataBaseName";
    private static final String KEY_TABLE = "DbTable";
    public static final String KEY_ROWID = "_rowid"; // 0
    public static final String KEY_ONE = "serial";
    public static final String KEY_TWO = "name";
    public static final String KEY_THREE = "place";
    public static final String KEY_FOUR = "returned";
    /**/

    private static final String DATABASE_CREATE = "CREATE TABLE DbTable (_rowid INTEGER PRIMARY KEY AUTOINCREMENT, "
            + "serial TEXT NOT NULL, "+ "name TEXT NOT NULL, " + "place TEXT NOT NULL, " + "returned TEXT NOT NULL);";  

    public Db(Context ctx) {
        this.mCtx = ctx;
    }

    public Db open() throws SQLException {
        mDbHelper = new DatabaseHelper(mCtx);
        mDb = mDbHelper.getWritableDatabase();
        return this;
    }

    public void close() {
        mDbHelper.close();
    }

    public long createEntry(String ax, String bx, String cx, String returned) {
        if (mDb == null) {
            this.open();
        }

        ContentValues cv = new ContentValues();
        cv.put(KEY_ONE, ax);
        cv.put(KEY_TWO,  bx);
        cv.put(KEY_THREE,  cx);
        cv.put(KEY_FOUR, returned);

        return mDb.insert(KEY_TABLE, null, cv);
    }

    public boolean deleteEntry(long rowId) {
        return mDb.delete(KEY_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
    }

    public boolean deleteAll() {
        if (mDb == null) {
            this.open();
        }

        return mDb.delete(KEY_TABLE, null, null) > 0;
    }

    public Cursor fetchAllColours() {
        if (mDb == null) {
            this.open();
        }

        return mDb.query(KEY_TABLE, new String[] { KEY_ROWID, KEY_TWO},
                null, null, null, null, null);
    }

    private static class DatabaseHelper extends SQLiteOpenHelper {
        DatabaseHelper(Context context) {
            super(context, KEY_DB, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL(DATABASE_CREATE);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
                    + newVersion + ", which will destroy all old data");
            db.execSQL("DROP TABLE IF EXISTS " + KEY_TABLE);
            onCreate(db);
        }
    }
}

LOGCAT

12-26 23:39:33.409: W/System.err(30879): java.lang.NullPointerException
12-26 23:39:33.409: W/System.err(30879):    at com.my.examples.SpinnerLoad.fillData(SpinnerLoad.java:59)
12-26 23:39:33.409: W/System.err(30879):    at com.my.examples.SpinnerLoad.onCreate(SpinnerLoad.java:30)
12-26 23:39:33.418: W/System.err(30879):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-26 23:39:33.418: W/System.err(30879):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
12-26 23:39:33.418: W/System.err(30879):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
12-26 23:39:33.418: W/System.err(30879):    at android.app.ActivityThread.access$2300(ActivityThread.java:125)
12-26 23:39:33.418: W/System.err(30879):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
12-26 23:39:33.418: W/System.err(30879):    at android.os.Handler.dispatchMessage(Handler.java:99)
12-26 23:39:33.418: W/System.err(30879):    at android.os.Looper.loop(Looper.java:123)
12-26 23:39:33.418: W/System.err(30879):    at android.app.ActivityThread.main(ActivityThread.java:4627)
12-26 23:39:33.428: W/System.err(30879):    at java.lang.reflect.Method.invokeNative(Native Method)
12-26 23:39:33.428: W/System.err(30879):    at java.lang.reflect.Method.invoke(Method.java:521)
12-26 23:39:33.428: W/System.err(30879):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-26 23:39:33.428: W/System.err(30879):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-26 23:39:33.428: W/System.err(30879):    at dalvik.system.NativeStart.main(Native Method)
12-26 23:40:00.628: E/Database(30879): Error inserting place=zyxwvutsr returned=null serial=123456789 name=abcdefghij
12-26 23:40:00.628: E/Database(30879): android.database.sqlite.SQLiteConstraintException: error code 19: constraint failed
12-26 23:40:00.628: E/Database(30879):  at android.database.sqlite.SQLiteStatement.native_execute(Native Method)
12-26 23:40:00.628: E/Database(30879):  at android.database.sqlite.SQLiteStatement.execute(SQLiteStatement.java:55)
12-26 23:40:00.628: E/Database(30879):  at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1549)
12-26 23:40:00.628: E/Database(30879):  at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1410)
12-26 23:40:00.628: E/Database(30879):  at com.my.examples.Db.createEntry(Db.java:56)
12-26 23:40:00.628: E/Database(30879):  at com.my.examples.SpinnerLoad.onClick(SpinnerLoad.java:86)
12-26 23:40:00.628: E/Database(30879):  at android.view.View.performClick(View.java:2408)
12-26 23:40:00.628: E/Database(30879):  at android.view.View$PerformClick.run(View.java:8816)
12-26 23:40:00.628: E/Database(30879):  at android.os.Handler.handleCallback(Handler.java:587)
12-26 23:40:00.628: E/Database(30879):  at android.os.Handler.dispatchMessage(Handler.java:92)
12-26 23:40:00.628: E/Database(30879):  at android.os.Looper.loop(Looper.java:123)
12-26 23:40:00.628: E/Database(30879):  at android.app.ActivityThread.main(ActivityThread.java:4627)
12-26 23:40:00.628: E/Database(30879):  at java.lang.reflect.Method.invokeNative(Native Method)
12-26 23:40:00.628: E/Database(30879):  at java.lang.reflect.Method.invoke(Method.java:521)
12-26 23:40:00.628: E/Database(30879):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-26 23:40:00.628: E/Database(30879):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-26 23:40:00.628: E/Database(30879):  at dalvik.system.NativeStart.main(Native Method)
12-26 23:40:00.628: W/System.err(30879): java.lang.NullPointerException
12-26 23:40:00.639: W/System.err(30879):    at com.my.examples.SpinnerLoad.fillData(SpinnerLoad.java:59)
12-26 23:40:00.639: W/System.err(30879):    at com.my.examples.SpinnerLoad.onClick(SpinnerLoad.java:89)
12-26 23:40:00.639: W/System.err(30879):    at android.view.View.performClick(View.java:2408)
12-26 23:40:00.639: W/System.err(30879):    at android.view.View$PerformClick.run(View.java:8816)
12-26 23:40:00.639: W/System.err(30879):    at android.os.Handler.handleCallback(Handler.java:587)
12-26 23:40:00.639: W/System.err(30879):    at android.os.Handler.dispatchMessage(Handler.java:92)
12-26 23:40:00.639: W/System.err(30879):    at android.os.Looper.loop(Looper.java:123)
12-26 23:40:00.639: W/System.err(30879):    at android.app.ActivityThread.main(ActivityThread.java:4627)
12-26 23:40:00.639: W/System.err(30879):    at java.lang.reflect.Method.invokeNative(Native Method)
12-26 23:40:00.649: W/System.err(30879):    at java.lang.reflect.Method.invoke(Method.java:521)
12-26 23:40:00.649: W/System.err(30879):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
12-26 23:40:00.649: W/System.err(30879):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
12-26 23:40:00.649: W/System.err(30879):    at dalvik.system.NativeStart.main(Native Method)

With the log cat, I can do just about the beginner Newbie stuff lol .. but I have looked it over a couple times and side by side with the original and not sure what i might have messed up. Hoping someone might be able to shed little light on this for me, if any more info is needed please let me know. Thanks


Solution

  • Why you are referencing Spinner two times

     spinner = (Spinner) findViewById(R.id.spinLoad_spinner);
    

    here

    fillData();
    spinner = (Spinner) findViewById(R.id.spinLoad_spinner);
    ....
    

    and here

     private void fillData() {
            try {
                Cursor coloursCursor;
                spinner = (Spinner) findViewById(R.id.spinLoad_spinner);
    ....