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.boko.vimusic.ui.fragments.profile; import java.util.List; import android.app.Activity; 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.view.ContextMenu; import android.view.ContextMenu.ContextMenuInfo; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.SubMenu; import android.view.View; import android.view.ViewGroup; import android.widget.AbsListView; import android.widget.AdapterView; import android.widget.AdapterView.AdapterContextMenuInfo; import android.widget.AdapterView.OnItemClickListener; import android.widget.ListView; import com.boko.vimusic.Config; import com.boko.vimusic.R; import com.boko.vimusic.adapters.ArtistAlbumAdapter; import com.boko.vimusic.loaders.ArtistAlbumLoader; import com.boko.vimusic.menu.CreateNewPlaylist; import com.boko.vimusic.menu.DeleteDialog; import com.boko.vimusic.menu.FragmentMenuItems; import com.boko.vimusic.model.Album; import com.boko.vimusic.model.Song; import com.boko.vimusic.recycler.RecycleHolder; import com.boko.vimusic.utils.MusicUtils; import com.boko.vimusic.utils.NavUtils; import com.boko.vimusic.widgets.ProfileTabCarousel; import com.boko.vimusic.widgets.VerticalScrollListener; import com.boko.vimusic.widgets.VerticalScrollListener.ScrollableHeader; /** * This class is used to display all of the albums from a particular artist. * * @author Andrew Neal (andrewdneal@gmail.com) */ public class ArtistAlbumFragment extends Fragment implements LoaderCallbacks<List<Album>>, OnItemClickListener { /** * Used to keep context menu items from bleeding into other fragments */ private static final int GROUP_ID = 10; /** * LoaderCallbacks identifier */ private static final int LOADER = 0; /** * The adapter for the grid */ private ArtistAlbumAdapter mAdapter; /** * The list view */ private ListView mListView; /** * Album song list */ private Song[] mAlbumList; /** * Represents an album */ private Album mAlbum; /** * Profile header */ private ProfileTabCarousel mProfileTabCarousel; /** * Empty constructor as per the {@link Fragment} documentation */ public ArtistAlbumFragment() { } /** * {@inheritDoc} */ @Override public void onAttach(final Activity activity) { super.onAttach(activity); mProfileTabCarousel = (ProfileTabCarousel) activity.findViewById(R.id.acivity_profile_base_tab_carousel); } /** * {@inheritDoc} */ @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Create the adpater mAdapter = new ArtistAlbumAdapter(getActivity(), R.layout.list_item_detailed_no_background); } /** * {@inheritDoc} */ @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { // The View for the fragment's UI final ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.list_base, null); // Initialize the list mListView = (ListView) rootView.findViewById(R.id.list_base); // Set the data behind the grid 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 songs from the selected album mListView.setOnItemClickListener(this); // To help make scrolling smooth mListView.setOnScrollListener(new VerticalScrollListener(mScrollableHeader, mProfileTabCarousel, 1)); // Remove the scrollbars and padding for the fast scroll mListView.setVerticalScrollBarEnabled(false); mListView.setFastScrollEnabled(false); mListView.setPadding(0, 0, 0, 0); return rootView; } /** * {@inheritDoc} */ @Override public void onActivityCreated(final Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); // Enable the options menu setHasOptionsMenu(true); // Start the loader final Bundle arguments = getArguments(); if (arguments != null) { getLoaderManager().initLoader(LOADER, arguments, this); } } /** * {@inheritDoc} */ @Override public void onPause() { super.onPause(); mAdapter.flush(); } /** * {@inheritDoc} */ @Override public void onSaveInstanceState(final Bundle outState) { super.onSaveInstanceState(outState); outState.putAll(getArguments() != null ? getArguments() : new Bundle()); } /** * {@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 album mAlbum = mAdapter.getItem(info.position - 1); // Create a list of the album's songs mAlbumList = MusicUtils.getSongListForAlbum(getActivity(), mAlbum.getId()); // Play the album menu.add(GROUP_ID, FragmentMenuItems.PLAY_SELECTION, Menu.NONE, getString(R.string.context_menu_play_selection)); // Add the album to the queue menu.add(GROUP_ID, FragmentMenuItems.ADD_TO_QUEUE, Menu.NONE, getString(R.string.add_to_queue)); // Add the album to a playlist final SubMenu subMenu = menu.addSubMenu(GROUP_ID, FragmentMenuItems.ADD_TO_PLAYLIST, Menu.NONE, R.string.add_to_playlist); MusicUtils.makePlaylistMenu(getActivity(), GROUP_ID, subMenu, false); // Delete the album menu.add(GROUP_ID, FragmentMenuItems.DELETE, Menu.NONE, getString(R.string.context_menu_delete)); } /** * {@inheritDoc} */ @Override public boolean onContextItemSelected(final MenuItem item) { // Avoid leaking context menu selections if (item.getGroupId() == GROUP_ID) { switch (item.getItemId()) { case FragmentMenuItems.PLAY_SELECTION: MusicUtils.playAll(getActivity(), mAlbumList, 0, false); return true; case FragmentMenuItems.ADD_TO_QUEUE: MusicUtils.addToQueue(getActivity(), mAlbumList); return true; case FragmentMenuItems.NEW_PLAYLIST: CreateNewPlaylist.getInstance(mAlbumList).show(getFragmentManager(), "CreatePlaylist"); return true; case FragmentMenuItems.PLAYLIST_SELECTED: final String id = item.getIntent().getStringExtra("playlist"); MusicUtils.addToPlaylist(getActivity(), mAlbumList, id); return true; case FragmentMenuItems.DELETE: DeleteDialog.newInstance(mAlbum.getName(), mAlbumList, null).show(getFragmentManager(), "DeleteDialog"); refresh(); 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) { if (position == 0) { return; } mAlbum = mAdapter.getItem(position - 1); NavUtils.openAlbumProfile(getActivity(), mAlbum.getName(), mAlbum.mArtistName, mAlbum.getId()); getActivity().finish(); } /** * {@inheritDoc} */ @Override public Loader<List<Album>> onCreateLoader(final int id, final Bundle args) { return new ArtistAlbumLoader(getActivity(), args.getString(Config.ID)); } /** * {@inheritDoc} */ @Override public void onLoadFinished(final Loader<List<Album>> loader, final List<Album> data) { // Check for any errors if (data.isEmpty()) { return; } // Start fresh mAdapter.unload(); // Return the correct count mAdapter.setCount(data); // Add the data to the adpater for (final Album album : data) { mAdapter.add(album); } } /** * {@inheritDoc} */ @Override public void onLoaderReset(final Loader<List<Album>> loader) { // Clear the data in the adapter mAdapter.unload(); } // Pause disk cache access to ensure smoother scrolling private final ScrollableHeader mScrollableHeader = new ScrollableHeader() { /** * {@inheritDoc} */ @Override public void onScrollStateChanged(final AbsListView view, final int scrollState) { if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_FLING || scrollState == AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL) { mAdapter.setPauseDiskCache(true); } else { mAdapter.setPauseDiskCache(false); mAdapter.notifyDataSetChanged(); } } }; /** * Restarts the loader. */ public void refresh() { // Scroll to the stop of the list before restarting the loader. // Otherwise, if the user has scrolled enough to move the header, it // becomes misplaced and needs to be reset. mListView.setSelection(0); // Wait a moment for the preference to change. SystemClock.sleep(10); mAdapter.notifyDataSetChanged(); getLoaderManager().restartLoader(LOADER, getArguments(), this); } }