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POPassing data to two different classes from click
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copied!<p>In my app i have a <code>ListActivity</code> that pulls data from a Database using <code>LoaderManager</code>. What i want to do is when an item is clicked, i want to start another activity (that pulls data from a database and displays a grid) and also pass the id to my content provider to perform the database query via the content provider. How can do this?</p> <p>I have searched for answers but i just can't seem to find one that solves this problem.</p> <p>I tried to use getIntent() in the ContentProvider but i found out that getIntent() doesn't work like in this question <a href="https://stackoverflow.com/questions/2091465/how-do-i-pass-data-between-activities-in-android">How do I pass data between Activities in Android application?</a></p> <p>This is the onListItemClick </p> <pre><code> protected void onListItemClick(ListView l, View v, int position, long id) { super.onListItemClick(l, v, position, id); startActivity(i); } </code></pre> <p>For me to create the next activty, i need to know which item was clicked (hence id). This id i what will be passed to Content Provider</p> <pre><code> public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { switch (mUriMatcher.match(uri)) { case QUESTIONS: Log.d(DBHelper.TAG, "fetching categories"); return myDH.fetchCatgories(); case GRID: //row here is the id from my list activity //myDH is an instance of my DB helper class return myDH.fetchQuestions(row); default: throw new IllegalArgumentException("Unsupported URI: " + uri); } } </code></pre> <p>I have set up a <code>urimatcher</code>. My question is how do i get that id from my list to become the argument for this query. I am using LoaderManager so i have to make the query from the content provider.</p> <p>This is the ContentProvider class</p> <pre><code> private static final int QUESTIONS = 1; private static final int GRID = 2; TestAdapter myTestAdapter; DBHelper myDH; private static final UriMatcher mUriMatcher; static { mUriMatcher = new UriMatcher(UriMatcher.NO_MATCH); mUriMatcher.addURI(AUTHORITY, BASE_PATH_CATEGORY, QUESTIONS); mUriMatcher.addURI(AUTHORITY, BASE_PATH_GRID, GRID); } @Override public boolean onCreate() { myDH = new DBHelper(getContext()); try { myDH.createDatabase(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } myDH.openDatabase(); return true; } @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { switch (mUriMatcher.match(uri)) { case QUESTIONS: Log.d(DBHelper.TAG, "fetching categories"); return myDH.fetchCatgories(); case GRID: //this is where i need the position that was clicked //so that i can use this value in the DBHelper. return myDH.fetchQuestions(row); default: throw new IllegalArgumentException("Unsupported URI: " + uri); } } </code></pre> <p>I am using the ContentProvider to communicate with my DBHelper. This is the relevant part of the code</p> <pre><code> //DBHelper Code public Cursor fetchQuestions(long row) throws SQLException{ Cursor cursor = myDataBase.rawQuery("select _id, used, question_level from questions_en where category" + " = " + row, null); return cursor; } </code></pre> <p>The cursor returned will be used in another activity to populate a grid. </p> <p>Without using LoaderManager, (this method is working but it uses the deprecated startManagingCursor) this is the relevant code for the listActivity </p> <pre><code> @Override protected void onListItemClick(ListView l, View v, int position, long id) { super.onListItemClick(l, v, position, id); Intent i = new Intent(this, QuestionSelection.class); i.putExtra(DBHelper.KEY_ID, id); startActivity(i); } </code></pre> <p>Now in the next Activity's onCreate:</p> <pre><code> protected void onCreate(Bundle savedInstanceState) { Bundle extras = getIntent().getExtras(); rowId = extras.getLong(DBHelper.KEY_ID); mDbHelper = new DBHelper(this); try { mDbHelper.createDatabase(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } mDbHelper.openDatabase(); Cursor cursor = mDbHelper.fetchQuestions(rowId); startManagingCursor(cursor); String[] from = {DBHelper.KEY_ID, "question_level", "used"}; int[] to = {R.id.grid_text, R.id.grid_image_right, R.id.grid_image_left}; GridView grid = (GridView)findViewById(R.id.question_grid); mAdapter = new SimpleCursorAdapter(this, R.layout.grid_item, cursor, from, to); grid.setAdapter(mAdapter); } </code></pre>

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