Java tutorial
/* * Copyright (C) 2012 Andrew Neal 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.andrew.apollo.ui.fragments; import android.content.Intent; import android.os.Bundle; import android.provider.MediaStore; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.Loader; import android.view.ContextMenu; import android.view.ContextMenu.ContextMenuInfo; import android.view.LayoutInflater; import android.view.Menu; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.AdapterView.AdapterContextMenuInfo; import android.widget.AdapterView.OnItemClickListener; import android.widget.ListView; import android.widget.TextView; import com.actionbarsherlock.app.SherlockFragment; import com.andrew.apollo.Config; import com.andrew.apollo.R; import com.andrew.apollo.adapters.GenreAdapter; import com.andrew.apollo.loaders.GenreLoader; import com.andrew.apollo.menu.FragmentMenuItems; import com.andrew.apollo.model.Genre; import com.andrew.apollo.recycler.RecycleHolder; import com.andrew.apollo.ui.activities.ProfileActivity; import com.andrew.apollo.utils.MusicUtils; import java.util.List; /** * This class is used to display all of the genres on a user's device. * * @author Andrew Neal (andrewdneal@gmail.com) */ public class GenreFragment extends SherlockFragment implements LoaderCallbacks<List<Genre>>, OnItemClickListener { /** * Used to keep context menu items from bleeding into other fragments */ private static final int GROUP_ID = 5; /** * LoaderCallbacks identifier */ private static final int LOADER = 0; /** * Fragment UI */ private ViewGroup mRootView; /** * The adapter for the list */ private GenreAdapter mAdapter; /** * The list view */ private ListView mListView; /** * Genre song list */ private long[] mGenreList; /** * Represents a genre */ private Genre mGenre; /** * Empty constructor as per the {@link Fragment} documentation */ public GenreFragment() { } /** * {@inheritDoc} */ @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Create the adpater mAdapter = new GenreAdapter(getSherlockActivity(), R.layout.list_item_simple); } /** * {@inheritDoc} */ @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { // The View for the fragment's UI mRootView = (ViewGroup) inflater.inflate(R.layout.list_base, null); // Initialize the list mListView = (ListView) mRootView.findViewById(R.id.list_base); // Set the data behind the list mListView.setAdapter(mAdapter); // Release any references to the recycled Views mListView.setRecyclerListener(new RecycleHolder()); // Listen for ContextMenus to be created mListView.setOnCreateContextMenuListener(this); // Show the albums and songs from the selected genre mListView.setOnItemClickListener(this); return mRootView; } /** * {@inheritDoc} */ @Override public void onActivityCreated(final Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); // Enable the options menu setHasOptionsMenu(true); // Start the loader getLoaderManager().initLoader(LOADER, null, this); } /** * {@inheritDoc} */ @Override public void onCreateContextMenu(final ContextMenu menu, final View v, final ContextMenuInfo menuInfo) { super.onCreateContextMenu(menu, v, menuInfo); // Get the position of the selected item final AdapterContextMenuInfo info = (AdapterContextMenuInfo) menuInfo; // Create a new genre mGenre = mAdapter.getItem(info.position); // Create a list of the genre's songs mGenreList = MusicUtils.getSongListForGenre(getSherlockActivity(), mGenre.mGenreId); // Play the genre menu.add(GROUP_ID, FragmentMenuItems.PLAY_SELECTION, Menu.NONE, R.string.context_menu_play_selection); // Add the genre to the queue menu.add(GROUP_ID, FragmentMenuItems.ADD_TO_QUEUE, Menu.NONE, R.string.add_to_queue); } /** * {@inheritDoc} */ @Override public boolean onContextItemSelected(final android.view.MenuItem item) { if (item.getGroupId() == GROUP_ID) { switch (item.getItemId()) { case FragmentMenuItems.PLAY_SELECTION: MusicUtils.playAll(getSherlockActivity(), mGenreList, 0, false); return true; case FragmentMenuItems.ADD_TO_QUEUE: MusicUtils.addToQueue(getSherlockActivity(), mGenreList); return true; default: break; } } return super.onContextItemSelected(item); } /** * {@inheritDoc} */ @Override public void onItemClick(final AdapterView<?> parent, final View view, final int position, final long id) { mGenre = mAdapter.getItem(position); // Create a new bundle to transfer the artist info final Bundle bundle = new Bundle(); bundle.putLong(Config.ID, Long.valueOf(mGenre.mGenreId)); bundle.putString(Config.MIME_TYPE, MediaStore.Audio.Genres.CONTENT_TYPE); bundle.putString(Config.NAME, mGenre.mGenreName); // Create the intent to launch the profile activity final Intent intent = new Intent(getSherlockActivity(), ProfileActivity.class); intent.putExtras(bundle); startActivity(intent); } /** * {@inheritDoc} */ @Override public Loader<List<Genre>> onCreateLoader(final int id, final Bundle args) { return new GenreLoader(getSherlockActivity()); } /** * {@inheritDoc} */ @Override public void onLoadFinished(final Loader<List<Genre>> loader, final List<Genre> data) { // Check for any errors if (data.isEmpty()) { // Set the empty text final TextView empty = (TextView) mRootView.findViewById(R.id.empty); empty.setText(getString(R.string.empty_music)); mListView.setEmptyView(empty); return; } // Start fresh mAdapter.unload(); // Add the data to the adpater for (final Genre genre : data) { mAdapter.add(genre); } // Build the cache mAdapter.buildCache(); } /** * {@inheritDoc} */ @Override public void onLoaderReset(final Loader<List<Genre>> loader) { // Clear the data in the adapter mAdapter.unload(); } }