Java tutorial
/* * Copyright 2016 andryr * * 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.andryr.musicplayer.fragments; import android.app.Activity; import android.app.ProgressDialog; import android.content.ContentResolver; import android.content.Intent; import android.os.AsyncTask; import android.os.Bundle; import android.support.v4.app.LoaderManager; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.Loader; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.Toolbar; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.MotionEvent; import android.view.View; import android.view.View.OnClickListener; import android.view.View.OnTouchListener; import android.view.ViewGroup; import android.widget.ImageButton; import android.widget.ImageView; import android.widget.TextView; import com.andryr.musicplayer.MainActivity; import com.andryr.musicplayer.R; import com.andryr.musicplayer.activities.MusicPicker; import com.andryr.musicplayer.utils.FavoritesHelper; import com.andryr.musicplayer.loaders.FavoritesLoader; import com.andryr.musicplayer.loaders.PlaylistLoader; import com.andryr.musicplayer.model.Playlist; import com.andryr.musicplayer.model.Song; import com.andryr.musicplayer.utils.Playlists; import com.andryr.musicplayer.utils.ThemeHelper; import com.andryr.musicplayer.widgets.DragRecyclerView; import com.andryr.musicplayer.widgets.FastScroller; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class PlaylistFragment extends BaseFragment { private static final String PARAM_PLAYLIST_FAVORITES = "favorites"; private static final String PARAM_PLAYLIST_ID = "playlist_id"; private static final String PARAM_PLAYLIST_NAME = "playlist_name"; private static final int PICK_MUSIC = 22; private MainActivity mActivity; private ArrayList<Song> mSongList = new ArrayList<>(); private DragRecyclerView mRecyclerView; private Playlist mPlaylist; private SongListAdapter mAdapter; private boolean mFavorites = false; private LoaderManager.LoaderCallbacks<List<Song>> mLoaderCallbacks = new LoaderCallbacks<List<Song>>() { @Override public Loader<List<Song>> onCreateLoader(int id, Bundle args) { if (mFavorites) { return new FavoritesLoader(getActivity()); } return new PlaylistLoader(getActivity(), mPlaylist.getId()); } @Override public void onLoadFinished(Loader<List<Song>> loader, List<Song> data) { mSongList = new ArrayList<>(data); mAdapter.notifyDataSetChanged(); } @Override public void onLoaderReset(Loader<List<Song>> loader) { } }; public static PlaylistFragment newInstance(Playlist playlist) { PlaylistFragment fragment = new PlaylistFragment(); Bundle args = new Bundle(); args.putLong(PARAM_PLAYLIST_ID, playlist.getId()); args.putString(PARAM_PLAYLIST_NAME, playlist.getName()); fragment.setArguments(args); return fragment; } public static PlaylistFragment newFavoritesFragment() { PlaylistFragment fragment = new PlaylistFragment(); Bundle args = new Bundle(); args.putBoolean(PARAM_PLAYLIST_FAVORITES, true); fragment.setArguments(args); return fragment; } private void selectSong(int position) { if (mActivity != null) { mActivity.onSongSelected(mSongList, position); } } @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { if (requestCode == PICK_MUSIC && resultCode == Activity.RESULT_OK) { long[] ids = data.getExtras().getLongArray(MusicPicker.EXTRA_IDS); addToPlaylist(ids); } } private void addToPlaylist(final long[] ids) { new AsyncTask<Void, Void, Void>() { private ProgressDialog mProgressDialog; @Override protected Void doInBackground(Void... params) { if (mFavorites) { for (long id : ids) { FavoritesHelper.addFavorite(getActivity(), id); } } else { ContentResolver resolver = getActivity().getContentResolver(); for (long id : ids) { Playlists.addSongToPlaylist(resolver, mPlaylist.getId(), id); } } return null; } @Override protected void onPreExecute() { mProgressDialog = ProgressDialog.show(getActivity(), getString(R.string.loading), getString(R.string.adding_songs_to_playlist), true); } @Override protected void onPostExecute(Void aVoid) { mProgressDialog.dismiss(); getLoaderManager().restartLoader(0, null, mLoaderCallbacks); } }.execute(); } @Override public void onAttach(Activity activity) { super.onAttach(activity); try { mActivity = (MainActivity) activity; } catch (ClassCastException e) { throw new ClassCastException(activity.toString() + " must implement OnFragmentInteractionListener"); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Bundle args = getArguments(); setHasOptionsMenu(true); if (args != null) { if (args.getBoolean(PARAM_PLAYLIST_FAVORITES)) { mFavorites = true; } else { long id = args.getLong(PARAM_PLAYLIST_ID); String name = args.getString(PARAM_PLAYLIST_NAME); mPlaylist = new Playlist(id, name); } } } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_playlist, container, false); mRecyclerView = (DragRecyclerView) rootView.findViewById(R.id.list_view); mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity())); mAdapter = new SongListAdapter(); mRecyclerView.setAdapter(mAdapter); mRecyclerView.setOnItemMovedListener(new DragRecyclerView.OnItemMovedListener() { @Override public void onItemMoved(int oldPosition, int newPosition) { mAdapter.moveItem(oldPosition, newPosition); } }); FastScroller scroller = (FastScroller) rootView.findViewById(R.id.fastscroller); scroller.setSectionIndexer(mAdapter); scroller.setRecyclerView(mRecyclerView); Toolbar toolbar = (Toolbar) rootView.findViewById(R.id.toolbar); toolbar.setVisibility(View.VISIBLE); AppCompatActivity activity = (AppCompatActivity) getActivity(); activity.setSupportActionBar(toolbar); activity.getSupportActionBar().setDisplayHomeAsUpEnabled(true); return rootView; } @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); load(); } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); } @Override public void onDetach() { super.onDetach(); mActivity = null; } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { super.onCreateOptionsMenu(menu, inflater); inflater.inflate(R.menu.playlist, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.action_add_item: startActivityForResult(new Intent(getActivity(), MusicPicker.class), PICK_MUSIC); break; } return super.onOptionsItemSelected(item); } @Override public void load() { getLoaderManager().restartLoader(0, null, mLoaderCallbacks); } class SongViewHolder extends RecyclerView.ViewHolder implements OnClickListener, OnTouchListener { View itemView; TextView vTitle; TextView vArtist; ImageButton vReorderButton; public SongViewHolder(View itemView) { super(itemView); this.itemView = itemView; vTitle = (TextView) itemView.findViewById(R.id.title); vArtist = (TextView) itemView.findViewById(R.id.artist); vReorderButton = (ImageButton) itemView.findViewById(R.id.reorder_button); itemView.findViewById(R.id.song_info).setOnClickListener(this); itemView.findViewById(R.id.delete_button).setOnClickListener(this); vReorderButton.setOnTouchListener(this); ThemeHelper.tintImageView(getActivity(), vReorderButton); ThemeHelper.tintImageView(getActivity(), (ImageView) itemView.findViewById(R.id.delete_button)); } @Override public void onClick(View v) { int position = getAdapterPosition(); switch (v.getId()) { case R.id.song_info: selectSong(position); break; case R.id.delete_button: mAdapter.removeItem(position); break; } } @Override public boolean onTouch(View v, MotionEvent event) { mRecyclerView.startDrag(itemView); return false; } } class SongListAdapter extends RecyclerView.Adapter<SongViewHolder> implements FastScroller.SectionIndexer { @Override public SongViewHolder onCreateViewHolder(ViewGroup parent, int type) { View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.playlist_item, parent, false); SongViewHolder viewHolder = new SongViewHolder(itemView); return viewHolder; } @Override public void onBindViewHolder(SongViewHolder viewHolder, int position) { Song song = mSongList.get(position); viewHolder.vTitle.setText(song.getTitle()); viewHolder.vArtist.setText(song.getArtist()); } @Override public int getItemCount() { return mSongList.size(); } public void moveItem(int oldPosition, int newPosition) { if (oldPosition < 0 || oldPosition >= mSongList.size() || newPosition < 0 || newPosition >= mSongList.size()) { return; } Collections.swap(mSongList, oldPosition, newPosition); if (!mFavorites) { Playlists.moveItem(getActivity().getContentResolver(), mPlaylist.getId(), oldPosition, newPosition); } notifyItemMoved(oldPosition, newPosition); } public void removeItem(int position) { Song s = mSongList.remove(position); if (mFavorites) { FavoritesHelper.removeFromFavorites(getActivity(), s.getId()); } else { Playlists.removeFromPlaylist(getActivity().getContentResolver(), mPlaylist.getId(), s.getId()); } notifyItemRemoved(position); } @Override public String getSectionForPosition(int position) { return mSongList.get(position).getTitle().substring(0, 1); } } }