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.app.Activity; import android.database.Cursor; import android.os.Bundle; import android.os.SystemClock; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.Loader; import android.text.TextUtils; import android.view.ContextMenu; import android.view.ContextMenu.ContextMenuInfo; import android.view.LayoutInflater; import android.view.Menu; import android.view.SubMenu; 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.MusicStateListener; import com.andrew.apollo.R; import com.andrew.apollo.adapters.SongAdapter; import com.andrew.apollo.loaders.SongLoader; import com.andrew.apollo.menu.CreateNewPlaylist; import com.andrew.apollo.menu.DeleteDialog; import com.andrew.apollo.menu.FragmentMenuItems; import com.andrew.apollo.model.Song; import com.andrew.apollo.provider.FavoritesStore; import com.andrew.apollo.recycler.RecycleHolder; import com.andrew.apollo.ui.activities.BaseActivity; import com.andrew.apollo.utils.MusicUtils; import com.andrew.apollo.utils.NavUtils; import com.viewpagerindicator.TitlePageIndicator; import java.util.List; /** * This class is used to display all of the songs on a user's device. * * @author Andrew Neal (andrewdneal@gmail.com) */ public class SongFragment extends SherlockFragment implements LoaderCallbacks<List<Song>>, OnItemClickListener, MusicStateListener { /** * Used to keep context menu items from bleeding into other fragments */ private static final int GROUP_ID = 4; /** * LoaderCallbacks identifier */ private static final int LOADER = 0; /** * Fragment UI */ private ViewGroup mRootView; /** * The adapter for the list */ private SongAdapter mAdapter; /** * The list view */ private ListView mListView; /** * Represents a song */ private Song mSong; /** * Position of a context menu item */ private int mSelectedPosition; /** * Id of a context menu item */ private long mSelectedId; /** * Song, album, and artist name used in the context menu */ private String mSongName, mAlbumName, mArtistName; /** * True if the list should execute {@code #restartLoader()}. */ private boolean mShouldRefresh = false; /** * Empty constructor as per the {@link Fragment} documentation */ public SongFragment() { } /** * {@inheritDoc} */ @Override public void onAttach(final Activity activity) { super.onAttach(activity); // Register the music status listener ((BaseActivity) activity).setMusicStateListenerListener(this); } /** * {@inheritDoc} */ @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Create the adpater mAdapter = new SongAdapter(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); // Play the selected song 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; mSelectedPosition = info.position; // Creat a new song mSong = mAdapter.getItem(mSelectedPosition); mSelectedId = Long.valueOf(mSong.mSongId); mSongName = mSong.mSongName; mAlbumName = mSong.mAlbumName; mArtistName = mSong.mArtistName; // Play the song menu.add(GROUP_ID, FragmentMenuItems.PLAY_SELECTION, Menu.NONE, getString(R.string.context_menu_play_selection)); // Add the song to the queue menu.add(GROUP_ID, FragmentMenuItems.ADD_TO_QUEUE, Menu.NONE, getString(R.string.add_to_queue)); // Add the song to a playlist final SubMenu subMenu = menu.addSubMenu(GROUP_ID, FragmentMenuItems.ADD_TO_PLAYLIST, Menu.NONE, R.string.add_to_playlist); MusicUtils.makePlaylistMenu(getSherlockActivity(), GROUP_ID, subMenu, true); // View more content by the song artist menu.add(GROUP_ID, FragmentMenuItems.MORE_BY_ARTIST, Menu.NONE, getString(R.string.context_menu_more_by_artist)); // Make the song a ringtone menu.add(GROUP_ID, FragmentMenuItems.USE_AS_RINGTONE, Menu.NONE, getString(R.string.context_menu_use_as_ringtone)); // Delete the song menu.add(GROUP_ID, FragmentMenuItems.DELETE, Menu.NONE, getString(R.string.context_menu_delete)); } @Override public boolean onContextItemSelected(final android.view.MenuItem item) { if (item.getGroupId() == GROUP_ID) { switch (item.getItemId()) { case FragmentMenuItems.PLAY_SELECTION: MusicUtils.playAll(getSherlockActivity(), new long[] { mSelectedId }, 0, false); return true; case FragmentMenuItems.ADD_TO_QUEUE: MusicUtils.addToQueue(getSherlockActivity(), new long[] { mSelectedId }); return true; case FragmentMenuItems.ADD_TO_FAVORITES: FavoritesStore.getInstance(getSherlockActivity()).addSongId(Long.valueOf(mSelectedId), mSongName, mAlbumName, mArtistName); return true; case FragmentMenuItems.NEW_PLAYLIST: CreateNewPlaylist.getInstance(new long[] { mSelectedId }).show(getFragmentManager(), "CreatePlaylist"); return true; case FragmentMenuItems.PLAYLIST_SELECTED: final long mPlaylistId = item.getIntent().getLongExtra("playlist", 0); MusicUtils.addToPlaylist(getSherlockActivity(), new long[] { mSelectedId }, mPlaylistId); return true; case FragmentMenuItems.MORE_BY_ARTIST: NavUtils.openArtistProfile(getSherlockActivity(), mArtistName); return true; case FragmentMenuItems.USE_AS_RINGTONE: MusicUtils.setRingtone(getSherlockActivity(), mSelectedId); return true; case FragmentMenuItems.DELETE: mShouldRefresh = true; DeleteDialog.newInstance(mSong.mSongName, new long[] { mSelectedId }, null) .show(getFragmentManager(), "DeleteDialog"); 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) { Cursor cursor = SongLoader.makeSongCursor(getSherlockActivity()); final long[] list = MusicUtils.getSongListForCursor(cursor); MusicUtils.playAll(getSherlockActivity(), list, position, false); cursor.close(); cursor = null; } /** * {@inheritDoc} */ @Override public Loader<List<Song>> onCreateLoader(final int id, final Bundle args) { return new SongLoader(getSherlockActivity()); } /** * {@inheritDoc} */ @Override public void onLoadFinished(final Loader<List<Song>> loader, final List<Song> 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 Song song : data) { mAdapter.add(song); } // Build the cache mAdapter.buildCache(); } /** * {@inheritDoc} */ @Override public void onLoaderReset(final Loader<List<Song>> loader) { // Clear the data in the adapter mAdapter.unload(); } /** * Scrolls the list to the currently playing song when the user touches the * header in the {@link TitlePageIndicator}. */ public void scrollToCurrentSong() { final int currentSongPosition = getItemPositionBySong(); if (currentSongPosition != 0) { mListView.setSelection(currentSongPosition); } } /** * @return The position of an item in the list based on the name of the * currently playing song. */ private int getItemPositionBySong() { final String trackName = String.valueOf(MusicUtils.getCurrentAudioId()); if (mAdapter == null || TextUtils.isEmpty(trackName)) { return 0; } for (int i = 0; i < mAdapter.getCount(); i++) { if (mAdapter.getItem(i).mSongId.equals(trackName)) { return i; } } return 0; } /** * Restarts the loader. */ public void refresh() { // Wait a moment for the preference to change. SystemClock.sleep(10); getLoaderManager().restartLoader(LOADER, null, this); } /** * {@inheritDoc} */ @Override public void restartLoader() { // Update the list when the user deletes any items if (mShouldRefresh) { getLoaderManager().restartLoader(LOADER, null, this); } mShouldRefresh = false; } /** * {@inheritDoc} */ @Override public void onMetaChanged() { // Nothing to do } }