Getting Context from Fragment extended Activity

Question

I have an "app" that has a tab layout with three tabs:
In the first I'm trying to retrieve some rows from a SQLite database and show them in a ListView.

The class which handle the tabs layout is called PageFragment:

public class PageFragment extends Fragment {
    public static final String ARG_PAGE = "ARG_PAGE";

    private int mPage;
    public MainActivity Main;

    public static PageFragment newInstance(int page) {
        Bundle args = new Bundle();
        args.putInt(ARG_PAGE, page);
        PageFragment fragment = new PageFragment();
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mPage = getArguments().getInt(ARG_PAGE);
    }

    ListView ItemsLst;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = null;
        switch(mPage)
        {
            case 1:
                view = inflater.inflate(R.layout.layout_schedule, container, false);

                DatabaseHandler db = new DatabaseHandler(getActivity().getApplicationContext());

                Medicine med = new Medicine("Cardioaspirina", "Pillola", 1, "2015-02-25", "12:00:00");

                db.AddMedicine(med);

                ScheduleList(view, db.GetAllMedicines());

                return view;
            case 2:
                view = inflater.inflate(R.layout.layout_settings, container, false);
                return view;
            case 3:
                view = inflater.inflate(R.layout.layout_info, container, false);
                return view;
        }
        return view;
    }

    public void ScheduleList(View v, List<Medicine> medicines) {
        ItemsLst = (ListView) v.findViewById(R.id.listview);
        ArrayAdapter<Medicine> adapter = new ArrayAdapter<Medicine>(getActivity(), android.R.layout.simple_list_item_1, medicines);
        ItemsLst.setAdapter(adapter);
    }
}

As you can see, in the onCreateView() method I manage the tabs layout. To retrieve data from the database i created a class named DatabaseHandler which has methods like AddRecord, GetRecord, GetAllRecords, etc. The issue is that the DatabaseHandler constructor needs a Context variable and I tried to give it the context using:

DatabaseHandler db = new DatabaseHandler(getActivity().getApplicationContext());

I also tried to use only getActivity() but it throws me NullPointerException.

If useful, here is the DatabaseHandler constructor:

public DatabaseHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

So anyone knows how to get the application context from the PageFragment class? Thank you in advance!

P.S. Here is the stack trace:

02-25 21:04:52.588    1947-1947/com.mms.dailypill I/art﹕ Not late-enabling -Xcheck:jni (already on)
02-25 21:04:53.092    1947-1959/com.mms.dailypill I/art﹕ Background sticky concurrent mark sweep GC freed 2943(255KB) AllocSpace objects, 0(0B) LOS objects, 29% free, 796KB/1135KB, paused 30.424ms total 49.618ms
02-25 21:04:53.093    1947-1972/com.mms.dailypill D/OpenGLRenderer﹕ Render dirty regions requested: true
02-25 21:04:53.094    1947-1947/com.mms.dailypill D/﹕ HostConnection::get() New Host Connection established 0xa6840570, tid 1947
02-25 21:04:53.106    1947-1947/com.mms.dailypill D/Atlas﹕ Validating map...
02-25 21:04:53.125    1947-1947/com.mms.dailypill E/SQLiteLog﹕ (1) near "TABLEDailyPill": syntax error
02-25 21:04:53.125    1947-1947/com.mms.dailypill D/AndroidRuntime﹕ Shutting down VM
02-25 21:04:53.183    1947-1947/com.mms.dailypill E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.mms.dailypill, PID: 1947
    android.database.sqlite.SQLiteException: near "TABLEDailyPill": syntax error (code 1): , while compiling: CREATE TABLEDailyPill(id INTEGER AUTOINCREMENT, name VARCHAR(50), format VARCHAR(15), amount INTEGER, exp_dateDATE, time HOUR, PRIMARY KEY(id));
            at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
            at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:889)
            at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:500)
            at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
            at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
            at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
            at android.database.sqlite.SQLiteDatabase.executeSql(SQLiteDatabase.java:1674)
            at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1605)
            at com.mms.dailypill.DatabaseHandler.onCreate(DatabaseHandler.java:63)
            at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:251)
            at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:163)
            at com.mms.dailypill.DatabaseHandler.AddMedicine(DatabaseHandler.java:84)
            at com.mms.dailypill.PageFragment.onCreateView(PageFragment.java:48)
            at android.support.v4.app.Fragment.performCreateView(Fragment.java:1786)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:947)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1126)
            at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
            at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
            at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:486)
            at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:1073)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:919)
            at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1441)
            at android.view.View.measure(View.java:17430)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:875)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
            at android.support.v7.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:453)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
            at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2560)
            at android.view.View.measure(View.java:17430)
            at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2001)
            at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1166)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1372)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5779)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
            at android.view.Choreographer.doCallbacks(Chor
02-25 21:04:55.795    1947-1947/com.mms.dailypill I/Process﹕ Sending signal. PID: 1947 SIG: 9

The context doesn't seem to give problems anymore... but i just read that the error is given by the SQL. I'll add the database class to the question. — Federico Belotti, Feb 25 '15 at 20:25

score 1 · Answer 1 · edited May 23 '17 at 12:16

First don't use getApplicationContext() because of the reason explain in this thread:

When to call activity context OR application context?

And for you question about how to get the context in your fragment create a global variable:

private Context context;

//onCreate method 
context = this;

Use this context on the creation of the view method.

Last thing is, I don't think your problem is with the context but with your data base creation because the log clear state there is a problem near "TABLEDailyPill": I think your query need to be fix.

score 0 · Answer 2 · answered Feb 25 '15 at 20:29

0

android.database.sqlite.SQLiteException: near "TABLEDailyPill": syntax error (code 1): , while compiling: CREATE TABLEDailyPill(id INTEGER AUTOINCREMENT, name VARCHAR(50), format VARCHAR(15), amount INTEGER, exp_dateDATE, time HOUR, PRIMARY KEY(id));

You are missing a space between TABLE and DailyPill, assuming that DailyPill is supposed to be the table name.

answered Feb 25 '15 at 20:29

CommonsWare

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I made a huge mistake swapping TABLE name with DATABASE name and also with the space after TABLE, but that isn't the problem... – Federico Belotti Feb 25 '15 at 20:41
@FedericoBelotti: If you read the error message, it very plainly is lacking a space between `TABLE` and `DailyPill`. Hence, it certainly is "the problem" for this stack trace. – CommonsWare Feb 25 '15 at 20:44
I edit the query and added the space and now the stack says: `02-25 21:42:24.721 1895-1895/com.mms.dailypill E/SQLiteLog﹕ (1) no such table: Medicines 02-25 21:42:24.722 1895-1895/com.mms.dailypill E/SQLiteDatabase﹕ Error inserting name=Cardioaspirina amount=1 time=12:00:00 format=Pillola exp_date=2015-02-25 android.database.sqlite.SQLiteException: no such table: Medicines (code 1): , while compiling: INSERT INTO Medicines(name,amount,time,format,exp_date) VALUES (?,?,?,?,?)` – Federico Belotti Feb 25 '15 at 20:52
@FedericoBelotti: Apparently, you have not created that table. – CommonsWare Feb 25 '15 at 21:03
I think it's better to reproject the database class, this thing is going me crazy! Anyway, thank you very much for availability! – Federico Belotti Feb 25 '15 at 21:10

Getting Context from Fragment extended Activity

2 Answers2