Refactor so we don't re-download the book list every time

Code is still pretty ugly, but I'm not sure on how to prettify it. Get
to that later.

MinimalBible/src/org/bspeice/minimalbible/activities/downloader/BookListFragment.java

@@ -120,18 +120,17 @@ public class BookListFragment extends Fragment {
 			f = null;
 			break;
 		}
-		DownloadManager dm = new DownloadManager();
+		DownloadManager dm = DownloadManager.getInstance();
 		
+		if (!dm.isLoaded()) {
 			ProgressDialog refreshDialog = new ProgressDialog(getActivity());	
-		if (dm.willRefresh()) {
 			refreshDialog.setMessage("Refreshing available modules...");
-		} else {
-			refreshDialog
-					.setMessage("Fetching available modules from cache...");
-		}
 			refreshDialog.setCancelable(false);
 			refreshDialog.show();
 			dm.fetchAvailableBooks(f, new DlBookRefreshListener(refreshDialog));
+		} else {
+			dm.fetchAvailableBooks(f, new DlBookRefreshListener(null));
+		}
 	}
 
 	private class DlBookRefreshListener implements

MinimalBible/src/org/bspeice/minimalbible/activities/downloader/BookRefreshTask.java

@@ -3,11 +3,15 @@ package org.bspeice.minimalbible.activities.downloader;
 import java.util.LinkedList;
 import java.util.List;
 
+import org.bspeice.minimalbible.MinimalBible;
+import org.bspeice.minimalbible.MinimalBibleConstants;
 import org.crosswire.jsword.book.Book;
 import org.crosswire.jsword.book.BookFilter;
 import org.crosswire.jsword.book.install.InstallException;
 import org.crosswire.jsword.book.install.Installer;
 
+import android.content.Context;
+import android.content.SharedPreferences;
 import android.os.AsyncTask;
 import android.util.Log;
 
@@ -16,16 +20,14 @@ public class BookRefreshTask extends AsyncTask<Installer, Integer, List<Book>> {
 	private static final String TAG = "BookRefreshTask";
 
 	private BookRefreshListener listener;
-	private boolean refresh;
 	private BookFilter filter;
 
-	public BookRefreshTask(boolean refresh, BookRefreshListener listener) {
-		this.refresh = refresh;
+	public BookRefreshTask(BookRefreshListener listener) {
 		this.listener = listener;
 	}
 
-	public BookRefreshTask(boolean refresh, BookFilter f, BookRefreshListener listener) {
-		this.refresh = refresh;
+	public BookRefreshTask(BookFilter f,
+			BookRefreshListener listener) {
 		this.filter = f;
 		this.listener = listener;
 	}
@@ -35,11 +37,13 @@ public class BookRefreshTask extends AsyncTask<Installer, Integer, List<Book>> {
 		List<Book> books = new LinkedList<Book>();
 
 		for (Installer i : params) {
-			if (refresh) {
+			if (doRefresh()) {
 				try {
 					i.reloadBookList();
 				} catch (InstallException e) {
-					Log.e(TAG, "Error downloading books from installer: " + i.toString(), e);
+					Log.e(TAG,
+							"Error downloading books from installer: "
+									+ i.toString(), e);
 				}
 			}
 
@@ -53,6 +57,21 @@ public class BookRefreshTask extends AsyncTask<Installer, Integer, List<Book>> {
 		return books;
 	}
 
+	private boolean doRefresh() {
+		// Check if we should refresh over the internet, or use the local copy
+		// TODO: Discover if we need to refresh over Internet, or use a cached
+		// copy - likely something time-based, also check network state.
+		// Fun fact - jSword handles the caching for us.
+
+		SharedPreferences prefs = MinimalBible.getAppContext()
+				.getSharedPreferences(
+						MinimalBibleConstants.DOWNLOAD_PREFS_FILE,
+						Context.MODE_PRIVATE);
+
+		// Refresh if download enabled
+		return prefs.getBoolean(MinimalBibleConstants.KEY_DOWNLOAD_ENABLED, false);
+	}
+
 	@Override
 	protected void onPostExecute(List<Book> result) {
 		super.onPostExecute(result);
@@ -63,5 +82,3 @@ public class BookRefreshTask extends AsyncTask<Installer, Integer, List<Book>> {
 		public void onRefreshComplete(List<Book> results);
 	}
 }
-
-

MinimalBible/src/org/bspeice/minimalbible/activities/downloader/DownloadManager.java

@@ -1,29 +1,36 @@
 package org.bspeice.minimalbible.activities.downloader;
 
+import java.util.List;
 import java.util.Map;
 
 import org.bspeice.minimalbible.MinimalBible;
-import org.bspeice.minimalbible.MinimalBibleConstants;
+import org.bspeice.minimalbible.activities.downloader.BookRefreshTask.BookRefreshListener;
+import org.crosswire.jsword.book.Book;
 import org.crosswire.jsword.book.BookCategory;
 import org.crosswire.jsword.book.BookFilter;
 import org.crosswire.jsword.book.install.InstallManager;
 import org.crosswire.jsword.book.install.Installer;
 
-import android.content.Context;
-import android.content.SharedPreferences;
 import android.util.Log;
 
 public class DownloadManager {
 
-	// TODO: Probably should be a singleton.
-
 	private final String TAG = "DownloadManager";
+	private static DownloadManager instance;
+	private List<Book> books;
 
 	public static final BookCategory[] VALID_CATEGORIES = { BookCategory.BIBLE,
 			BookCategory.COMMENTARY, BookCategory.DICTIONARY,
 			BookCategory.IMAGES, BookCategory.MAPS };
 
-	public DownloadManager() {
+	public static DownloadManager getInstance() {
+		if (instance == null) {
+			instance = new DownloadManager();
+		}
+		return instance;
+	}
+
+	private DownloadManager() {
 		setDownloadDir();
 	}
 
@@ -40,32 +47,30 @@ public class DownloadManager {
 	private BookRefreshTask _fetchAvailableBooks(BookFilter f,
 			BookRefreshTask.BookRefreshListener bookRefreshListener) {
 
-		Map<String, Installer> installers = getInstallers();
-
-		return (BookRefreshTask) new BookRefreshTask(willRefresh(),
-				bookRefreshListener).execute(installers.values().toArray(
-				new Installer[installers.size()]));
+		if (!isLoaded()) {
+			return (BookRefreshTask) new BookRefreshTask(
+					new DmBookRefreshListener(bookRefreshListener))
+					.execute(getInstallersArray());
+		} else {
+			return (BookRefreshTask) new NoopBookRefreshTask(books,
+					bookRefreshListener).execute(getInstallersArray());
+		}
 	}
 
-	public boolean willRefresh() {
-		// Method to determine if we need a refresh
-		// Public, so other modules can predict and take action accordingly.
-		// TODO: Discover if we need to refresh over Internet, or use a cached
-		// copy - likely something time-based, also check network state.
-		// Fun fact - jSword handles the caching for us.
-
-		SharedPreferences prefs = MinimalBible.getAppContext()
-				.getSharedPreferences(
-						MinimalBibleConstants.DOWNLOAD_PREFS_FILE,
-						Context.MODE_PRIVATE);
-
-		return (prefs.getBoolean(MinimalBibleConstants.KEY_DOWNLOAD_ENABLED, false));
+	public boolean isLoaded() {
+		// Let methods know if we're going to take a while to reload everything
+		return (books != null);
 	}
 
 	public Map<String, Installer> getInstallers() {
 		return new InstallManager().getInstallers();
 	}
 	
+	public Installer[] getInstallersArray() {
+		Map<String, Installer> installers = getInstallers();
+		return installers.values().toArray(new Installer[installers.size()]);
+	}
+
 	private void setDownloadDir() {
 		// We need to set the download directory for jSword to stick with
 		// Android.
@@ -74,4 +79,19 @@ public class DownloadManager {
 		System.setProperty("jsword.home", home);
 	}
 
+	// Create our own refresh listener to save a reference to the books
+	private class DmBookRefreshListener implements BookRefreshListener {
+		private BookRefreshListener listener;
+
+		public DmBookRefreshListener(BookRefreshListener listener) {
+			this.listener = listener;
+		}
+
+		@Override
+		public void onRefreshComplete(List<Book> results) {
+			books = results;
+			listener.onRefreshComplete(results);
+		}
+	}
+
 }

MinimalBible/src/org/bspeice/minimalbible/activities/downloader/NoopBookRefreshTask.java

@@ -0,0 +1,25 @@
+package org.bspeice.minimalbible.activities.downloader;
+
+import java.util.List;
+
+import org.crosswire.jsword.book.Book;
+import org.crosswire.jsword.book.install.Installer;
+
+/*
+ * There's probably a better way of doing this, but this allows me to avoid networking,
+ * while still maintaining the code structure of being asynchronous.
+ */
+public class NoopBookRefreshTask extends BookRefreshTask {
+	BookRefreshListener listener;
+	List<Book> books;
+	
+	public NoopBookRefreshTask(List<Book> books, BookRefreshListener listener) {
+		super(listener);
+		this.books = books;
+	}
+	
+	@Override
+	protected List<Book> doInBackground(Installer... params) {
+		return books;
+	}
+}