/*
* Copyright (C) 2014 Saravan Pantham
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.aniruddhc.acemusic.player.DBHelpers;
import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.Arrays;
import android.content.ContentResolver;
import android.content.Context;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.Uri;
import android.support.v4.content.AsyncTaskLoader;
/*********************************************************************************
* Custom CursorLoader class that adds support for SQLite databases.
* The default CursorLoader that's supplied through the Android
* compatibility library only supports ContentProviders.
*
* Since this app maintains it's own music library/database and doesn't depend
* on Android's MediaStore ContentProvider, we need a way to channel
* queries directly to a raw SQLite database. This class simply replaces
* every instance of a ContentProvider query with queries that connect
* directly to an SQLite database.
*
* @author Saravan Pantham
*********************************************************************************/
public class SQLiteDBCursorLoader extends AsyncTaskLoader<Cursor> {
final ForceLoadContentObserver mObserver;
String mTableName;
String[] mProjection;
String mSelection;
String[] mSelectionArgs;
String mSortOrder;
String mLimit = null;
Cursor mCursor;
boolean mDistinctPlaylists = false;
boolean mDistinctGenres = false;
String mDistinctField = "";
/* Runs on a worker thread */
@Override
public Cursor loadInBackground() {
/* //Retrieve the appropriate cursor based on @param mDistinctField;
Cursor cursor = null;
if (mDistinctField.equals("PLAYLISTS")) {
DBAccessHelper playlistsDBHelper = new DBAccessHelper(getContext());
cursor = playlistsDBHelper.getAllUniquePlaylists(mSelection);
} else if (mDistinctField.equals("GENRES")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllUniqueGenres(mSelection);
} else if (mDistinctField.equals("ARTISTS")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllUniqueArtists(mSelection);
} else if (mDistinctField.equals("ALBUMS")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllUniqueAlbums(mSelection);
} else if (mDistinctField.equals("SONGS")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllSongsSearchable(mSelection);
} else if (mDistinctField.equals("ARTISTS_FLIPPED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllUniqueAlbumsByArtist(mSelection);
} else if (mDistinctField.equals("ARTISTS_FLIPPED_SONGS")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllSongsByArtistAlbum(mSelection);
} else if (mDistinctField.equals("ALBUMS_FLIPPED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllSongsByArtistAlbum(mSelection);
} else if (mDistinctField.equals("TOP_25_PLAYED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getTop25PlayedTracks(mSelection);
} else if (mDistinctField.equals("RECENTLY_ADDED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getRecentlyAddedSongs(mSelection);
} else if (mDistinctField.equals("TOP_RATED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getTopRatedSongs(mSelection);
} else if (mDistinctField.equals("RECENTLY_PLAYED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getRecentlyPlayedSongs(mSelection);
} else if (mDistinctField.equals("GENRES_FLIPPED")) {
DBAccessHelper dBHelper = new DBAccessHelper(getContext());
cursor = dBHelper.getAllSongsInGenre(mSelection);
}
if (cursor != null) {
// Ensure the cursor window is filled
cursor.getCount();
registerContentObserver(cursor, mObserver);
}*/
return null;
}
/**
* Registers an observer to get notifications from the content mApp
* when the cursor needs to be refreshed.
*/
void registerContentObserver(Cursor cursor, ContentObserver observer) {
cursor.registerContentObserver(mObserver);
}
/* Runs on the UI thread */
@Override
public void deliverResult(Cursor cursor) {
if (isReset()) {
// An async query came in while the loader is stopped
if (cursor != null) {
cursor.close();
}
return;
}
Cursor oldCursor = mCursor;
mCursor = cursor;
if (isStarted()) {
super.deliverResult(cursor);
}
if (oldCursor != null && oldCursor != cursor && !oldCursor.isClosed()) {
oldCursor.close();
}
}
/**
* Creates an empty unspecified CursorLoader. You must follow this with
* calls to {@link #setUri(Uri)}, {@link #setSelection(String)}, etc
* to specify the query to perform.
*/
public SQLiteDBCursorLoader(Context context) {
super(context);
mObserver = new ForceLoadContentObserver();
}
/**
* Creates a fully-specified CursorLoader. See
* {@link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*/
public SQLiteDBCursorLoader(Context context, String tableName, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
super(context);
mObserver = new ForceLoadContentObserver();
mTableName = tableName;
mProjection = projection;
mSelection = selection;
mSelectionArgs = selectionArgs;
mSortOrder = sortOrder;
}
/**
* Creates a fully-specified CursorLoader. See
* {@link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*/
public SQLiteDBCursorLoader(Context context, String tableName, String[] projection, String selection,
String[] selectionArgs, String sortOrder, String limit) {
super(context);
mObserver = new ForceLoadContentObserver();
mTableName = tableName;
mProjection = projection;
mSelection = selection;
mSelectionArgs = selectionArgs;
mSortOrder = sortOrder;
mLimit = limit;
}
/**
* Creates a fully-specified, DISTINCT CursorLoader. See
* {@link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*/
public SQLiteDBCursorLoader(Context context, boolean distinctPlaylists) {
super(context);
mDistinctPlaylists = distinctPlaylists;
mObserver = new ForceLoadContentObserver();
}
/**
* Creates a fully-specified, DISTINCT CursorLoader. See
* {@link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*
* boolean dummy is a dummy variable, used to differentiate constructors.
*/
public SQLiteDBCursorLoader(Context context, boolean distinctGenres, boolean dummy) {
super(context);
mDistinctGenres = distinctGenres;
mObserver = new ForceLoadContentObserver();
}
/**
* Creates a fully-specified, DISTINCT CursorLoader. See
* {@link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*
* boolean dummy is a dummy variable, used to differentiate constructors.
*/
public SQLiteDBCursorLoader(Context context, String distinctField, String selection) {
super(context);
mDistinctField = distinctField;
mSelection = selection;
mObserver = new ForceLoadContentObserver();
}
/**
* Starts an asynchronous load of the contacts list data. When the result is ready the callbacks
* will be called on the UI thread. If a previous load has been completed and is still valid
* the result may be passed to the callbacks immediately.
*
* Must be called from the UI thread
*/
@Override
protected void onStartLoading() {
if (mCursor != null) {
deliverResult(mCursor);
}
if (takeContentChanged() || mCursor == null) {
forceLoad();
}
}
/**
* Must be called from the UI thread
*/
@Override
protected void onStopLoading() {
// Attempt to cancel the current load task if possible.
cancelLoad();
}
@Override
public void onCanceled(Cursor cursor) {
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
}
@Override
protected void onReset() {
super.onReset();
// Ensure the loader is stopped
onStopLoading();
if (mCursor != null && !mCursor.isClosed()) {
mCursor.close();
}
mCursor = null;
}
public String getTableName() {
return mTableName;
}
public void setUri(String tableName) {
mTableName = tableName;
}
public String[] getProjection() {
return mProjection;
}
public void setProjection(String[] projection) {
mProjection = projection;
}
public String getSelection() {
return mSelection;
}
public void setSelection(String selection) {
mSelection = selection;
}
public String[] getSelectionArgs() {
return mSelectionArgs;
}
public void setSelectionArgs(String[] selectionArgs) {
mSelectionArgs = selectionArgs;
}
public String getSortOrder() {
return mSortOrder;
}
public void setSortOrder(String sortOrder) {
mSortOrder = sortOrder;
}
@Override
public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
super.dump(prefix, fd, writer, args);
writer.print(prefix); writer.print("mUri="); writer.println(mTableName);
writer.print(prefix); writer.print("mProjection=");
writer.println(Arrays.toString(mProjection));
writer.print(prefix); writer.print("mSelection="); writer.println(mSelection);
writer.print(prefix); writer.print("mSelectionArgs=");
writer.println(Arrays.toString(mSelectionArgs));
writer.print(prefix); writer.print("mSortOrder="); writer.println(mSortOrder);
writer.print(prefix); writer.print("mCursor="); writer.println(mCursor);
writer.print(prefix); writer.print("mContentChanged="); //writer.println(mContentChanged);
}
}