Cierre del cursor en onPostExecute no produce nada

Estoy utilizando AsyncTask para cargar datos de una base de datos SQLite y luego proporcionar datos a un Recycler View utilizando un StaggeredLayoutManager y CustomListAdapter.

Si no cierra el cursor del método doInBackground en onPostExecuteMethod, la transición de la actividad anterior es laggy, y androide logcat dice "Omitido 52 cuadros".

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Si cierro el cursor, al final del método Post Execute, el retraso no se produce, pero no se procesa nada dentro de la actividad. (Recycler View no muestra nada).

@Override protected void onPostExecute(Void Void) { c.close(); swipeRefreshLayout.setRefreshing(false); swipeRefreshLayout.setOnRefreshListener( new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { new MyTask().execute(); } }); swipeRefreshLayout.setColorSchemeColors(getResources().getIntArray(R.array.swipeRefreshColors)); } 

método doInBackground

  try { myDb = new SavedData(getApplicationContext()); writeableDatabase = myDb.getReadableDatabase(); final String[] projection = {SavedData.COLUMN_NAME_ENTRY_ID, SavedData.COLUMN_NAME_PRICE, SavedData.COLUMN_NAME_SHIPPING, SavedData.COLUMN_NAME_WEIGHT, SavedData.COLUMN_NAME_PRODUCT}; sortOrder = BookSave.COLUMN_NAME_ENTRY_ID + " DESC"; c = writeableDatabase.query( SavedData.TABLE_NAME, projection, null, null, null, null, sortOrder ); m = new MyListCursorAdapter(getApplicationContext(), c); gaggeredGridLayoutManager = new StaggeredGridLayoutManager(NUM, 1); } catch (Exception e) { e.printStackTrace(); } finally { } 

La clase BaseAdapter

 import android.content.Context; import android.database.Cursor; import android.database.DataSetObserver; import android.support.v7.widget.RecyclerView; public abstract class CursorRecyclerViewAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> { private Context mContext; private Cursor mCursor; private boolean mDataValid; private int mRowIdColumn; private DataSetObserver mDataSetObserver; public CursorRecyclerViewAdapter(Context context, Cursor cursor) { mContext = context; mCursor = cursor; mDataValid = cursor != null; mRowIdColumn = mDataValid ? mCursor.getColumnIndex("_id") : -1; mDataSetObserver = new NotifyingDataSetObserver(); if (mCursor != null) { mCursor.registerDataSetObserver(mDataSetObserver); } } public Cursor getCursor() { return mCursor; } @Override public int getItemCount() { if (mDataValid && mCursor != null) { return mCursor.getCount(); } return 0; } @Override public long getItemId(int position) { if (mDataValid && mCursor != null && mCursor.moveToPosition(position)) { return mCursor.getLong(mRowIdColumn); } return 0; } @Override public void setHasStableIds(boolean hasStableIds) { super.setHasStableIds(true); } public abstract void onBindViewHolder(VH viewHolder, Cursor cursor); @Override public void onBindViewHolder(VH viewHolder, int position) { if (!mDataValid) { throw new IllegalStateException("this should only be called when the cursor is valid"); } if (!mCursor.moveToPosition(position)) { throw new IllegalStateException("couldn't move cursor to position " + position); } onBindViewHolder(viewHolder, mCursor); } /** * Change the underlying cursor to a new cursor. If there is an existing cursor it will be * closed. */ public void changeCursor(Cursor cursor) { Cursor old = swapCursor(cursor); if (old != null) { old.close(); } } /** * Swap in a new Cursor, returning the old Cursor. Unlike * {@link #changeCursor(Cursor)}, the returned old Cursor is <em>not</em> * closed. */ public Cursor swapCursor(Cursor newCursor) { if (newCursor == mCursor) { return null; } final Cursor oldCursor = mCursor; if (oldCursor != null && mDataSetObserver != null) { oldCursor.unregisterDataSetObserver(mDataSetObserver); } mCursor = newCursor; if (mCursor != null) { if (mDataSetObserver != null) { mCursor.registerDataSetObserver(mDataSetObserver); } mRowIdColumn = newCursor.getColumnIndexOrThrow("_id"); mDataValid = true; notifyDataSetChanged(); } else { mRowIdColumn = -1; mDataValid = false; notifyDataSetChanged(); //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter } return oldCursor; } private class NotifyingDataSetObserver extends DataSetObserver { @Override public void onChanged() { super.onChanged(); mDataValid = true; notifyDataSetChanged(); } @Override public void onInvalidated() { super.onInvalidated(); mDataValid = false; notifyDataSetChanged(); //There is no notifyDataSetInvalidated() method in RecyclerView.Adapter } } } 

La clase de adaptador ampliada

 import android.content.Context; import android.content.Intent; import android.content.res.Resources; import android.database.Cursor; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Typeface; import android.os.AsyncTask; import android.support.v7.widget.CardView; import android.support.v7.widget.RecyclerView; import android.util.DisplayMetrics; import android.util.Log; import android.view.Display; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.Button; import android.widget.LinearLayout; import android.widget.TextView; public class MyListCursorAdapter extends CursorRecyclerViewAdapter<MyListCursorAdapter.ViewHolder> { private static final String TAG = "MyListCursorAdapter"; public MyListCursorAdapter(Context context, Cursor cursor) { super(context, cursor); } @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View itemView = LayoutInflater.from(parent.getContext()) .inflate(R.layout.productList, parent, false); ViewHolder vh = new ViewHolder(itemView); return vh; } @Override public void onBindViewHolder(final ViewHolder viewHolder, final Cursor cursor) { Book myListItem = Book.fromCursor(cursor); viewHolder.titleTextView.setText(myListItem.getTitle()); viewHolder.shippingTextView.setText(myListItem.getAShipping()); Log.d(TAG, "onBindViewHolder: "+viewHolder.isRecyclable()); } public static class ViewHolder extends RecyclerView.ViewHolder { public TextView shippingTextView; public TextView titleTextView; public LinearLayout insideCard; public Button payButton; public View seperator; public CardView cv; public View view; public ViewHolder(final View view) { super(view); WindowManager wm = (WindowManager) view.getContext().getSystemService(Context.WINDOW_SERVICE); Display display = wm.getDefaultDisplay(); DisplayMetrics DM = new DisplayMetrics(); display.getMetrics(DM); payButton = (Button) view.findViewById(R.id.readButton); seperator = view.findViewById(R.id.separator); titleTextView = (TextView) view.findViewById(R.id.titleTextView); insideCard = (LinearLayout) view.findViewById(R.id.insideCard); insideCard.getLayoutParams().width = (DM.widthPixels / 2) - 24; shippingTextView = (TextView) view.findViewById(R.id.shippingTextView); //typeface Typeface light = Typeface.createFromAsset(titleTextView.getResources().getAssets(), "fonts/light.ttf"); titleTextView.setTypeface(light); Typeface regular = Typeface.createFromAsset(authorTextView.getResources().getAssets(), "fonts/thinItalic.ttf"); shippingTextView.setTypeface(regular); payButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent goToCheckout = new Intent(view.getContext(), ShowReader.class); goToCheckout.putExtra("PRODUCT_NAME", titleTextView.getText()); view.getContext().startActivity(goToCheckout); } }); setWidth((DM.widthPixels / 2) - 24); } public void setWidth(int a) { a = a - 8 * 4; payButton.getLayoutParams().width = a; seperator.getLayoutParams().width = a; } } } 

 //typeface Typeface light = Typeface.createFromAsset(titleTextView.getResources().getAssets(), "fonts/light.ttf"); titleTextView.setTypeface(light); Typeface regular = Typeface.createFromAsset(authorTextView.getResources().getAssets(), "fonts/thinItalic.ttf"); shippingTextView.setTypeface(regular); 

 public class MyFontProvider { private static final String TAG = MyFontProvider.class.getSimpleName(); private Map<String, Typeface> mCache; private static volatile MyFontProvider sInstance; public static MyFontProvider getInstance() { if (sInstance == null) { synchronized (MyFontProvider.class) { if (sInstance == null) { sInstance = new MyFontProvider(); } } } return sInstance; } private MyFontProvider() { mCache = new Hashtable<>(); } public synchronized Typeface getFont(String assetPath, Context context) { if (!mCache.containsKey(assetPath)) { try { Typeface t = Typeface.createFromAsset(context.getAssets(), assetPath); mCache.put(assetPath, t); } catch (Exception e) { Log.e(TAG, "Error getting typeface (" + assetPath + " ) " + e.getMessage()); return null; } } return mCache.get(assetPath); } } 

 //typeface Typeface light = Typeface.createFromAsset(titleTextView.getResources().getAssets(), "fonts/light.ttf"); titleTextView.setTypeface(light); Typeface regular = Typeface.createFromAsset(authorTextView.getResources().getAssets(), "fonts/thinItalic.ttf"); shippingTextView.setTypeface(regular); 

 //typeface titleTextView.setTypeface(MyFontProvider.getInstance().getFont("fonts/light.ttf",this)); shippingTextView.setTypeface(MyFontProvider.getInstance().getFont("fonts/thinItalic.ttf",this));