Java tutorial
/* * Copyright (C) 2011 The MusicMod Project * * 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 org.yammp.dialog; import org.yammp.Constants; import org.yammp.R; import org.yammp.YAMMPApplication; import org.yammp.util.MediaUtils; import android.app.AlertDialog; import android.app.Dialog; import android.content.ContentResolver; import android.content.DialogInterface; import android.content.DialogInterface.OnCancelListener; import android.content.DialogInterface.OnClickListener; import android.content.DialogInterface.OnShowListener; import android.database.Cursor; import android.media.AudioManager; import android.os.Bundle; import android.provider.MediaStore; import android.support.v4.app.FragmentActivity; import android.text.Editable; import android.text.TextWatcher; import android.util.DisplayMetrics; import android.widget.Button; import android.widget.EditText; import android.widget.LinearLayout; import android.widget.Toast; public class PlaylistDialog extends FragmentActivity implements Constants, TextWatcher, OnCancelListener, OnShowListener { private AlertDialog mPlaylistDialog; private String action; private EditText mPlaylist; private String mDefaultName, mOriginalName; private long mRenameId; private long[] mList = new long[] {}; private OnClickListener mRenamePlaylistListener = new OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { String name = mPlaylist.getText().toString(); mUtils.renamePlaylist(mRenameId, name); finish(); } }; private OnClickListener mCreatePlaylistListener = new OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { String name = mPlaylist.getText().toString(); if (name != null && name.length() > 0) { int id = idForplaylist(name); if (id >= 0) { mUtils.clearPlaylist(id); mUtils.addToPlaylist(mList, id); } else { long new_id = mUtils.createPlaylist(name); if (new_id >= 0) { mUtils.addToPlaylist(mList, new_id); } } finish(); } } }; private MediaUtils mUtils; @Override public void afterTextChanged(Editable s) { // don't care about this one } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { // don't care about this one } @Override public void onCancel(DialogInterface dialog) { if (dialog == mPlaylistDialog) { finish(); } } @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); mUtils = ((YAMMPApplication) getApplication()).getMediaUtils(); setContentView(new LinearLayout(this)); action = getIntent().getAction(); mRenameId = icicle != null ? icicle.getLong(INTENT_KEY_RENAME) : getIntent().getLongExtra(INTENT_KEY_RENAME, -1); mList = icicle != null ? icicle.getLongArray(INTENT_KEY_LIST) : getIntent().getLongArrayExtra(INTENT_KEY_LIST); if (INTENT_RENAME_PLAYLIST.equals(action)) { mOriginalName = nameForId(mRenameId); mDefaultName = icicle != null ? icicle.getString(INTENT_KEY_DEFAULT_NAME) : mOriginalName; } else if (INTENT_CREATE_PLAYLIST.equals(action)) { mDefaultName = icicle != null ? icicle.getString(INTENT_KEY_DEFAULT_NAME) : makePlaylistName(); mOriginalName = mDefaultName; } DisplayMetrics dm = new DisplayMetrics(); dm = getResources().getDisplayMetrics(); mPlaylistDialog = new AlertDialog.Builder(this).create(); mPlaylistDialog.setVolumeControlStream(AudioManager.STREAM_MUSIC); if (action != null && mRenameId >= 0 && mOriginalName != null || mDefaultName != null) { mPlaylist = new EditText(this); mPlaylist.setSingleLine(true); mPlaylist.setText(mDefaultName); mPlaylist.setSelection(mDefaultName.length()); mPlaylist.addTextChangedListener(this); mPlaylistDialog.setIcon(android.R.drawable.ic_dialog_info); String promptformat; String prompt = ""; if (INTENT_RENAME_PLAYLIST.equals(action)) { promptformat = getString(R.string.rename_playlist_prompt); prompt = String.format(promptformat, mOriginalName, mDefaultName); } else if (INTENT_CREATE_PLAYLIST.equals(action)) { promptformat = getString(R.string.create_playlist_prompt); prompt = String.format(promptformat, mDefaultName); } mPlaylistDialog.setTitle(prompt); mPlaylistDialog.setView(mPlaylist, (int) (8 * dm.density), (int) (8 * dm.density), (int) (8 * dm.density), (int) (4 * dm.density)); if (INTENT_RENAME_PLAYLIST.equals(action)) { mPlaylistDialog.setButton(Dialog.BUTTON_POSITIVE, getString(R.string.save), mRenamePlaylistListener); mPlaylistDialog.setOnShowListener(this); } else if (INTENT_CREATE_PLAYLIST.equals(action)) { mPlaylistDialog.setButton(Dialog.BUTTON_POSITIVE, getString(R.string.save), mCreatePlaylistListener); } mPlaylistDialog.setButton(Dialog.BUTTON_NEGATIVE, getString(android.R.string.cancel), new OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { finish(); } }); mPlaylistDialog.setOnCancelListener(this); mPlaylistDialog.show(); } else { Toast.makeText(this, R.string.error_bad_parameters, Toast.LENGTH_SHORT).show(); finish(); } } @Override public void onPause() { if (mPlaylistDialog != null && mPlaylistDialog.isShowing()) { mPlaylistDialog.dismiss(); } super.onPause(); } @Override public void onSaveInstanceState(Bundle outcicle) { if (INTENT_RENAME_PLAYLIST.equals(action)) { outcicle.putString(INTENT_KEY_DEFAULT_NAME, mPlaylist.getText().toString()); outcicle.putLong(INTENT_KEY_RENAME, mRenameId); } else if (INTENT_CREATE_PLAYLIST.equals(action)) { outcicle.putString(INTENT_KEY_DEFAULT_NAME, mPlaylist.getText().toString()); } } @Override public void onShow(DialogInterface dialog) { if (dialog == mPlaylistDialog) { setSaveButton(); } } @Override public void onTextChanged(CharSequence s, int start, int before, int count) { setSaveButton(); } private int idForplaylist(String name) { Cursor cursor = mUtils.query(MediaStore.Audio.Playlists.EXTERNAL_CONTENT_URI, new String[] { MediaStore.Audio.Playlists._ID }, MediaStore.Audio.Playlists.NAME + "=?", new String[] { name }, MediaStore.Audio.Playlists.NAME); int id = -1; if (cursor != null) { cursor.moveToFirst(); if (!cursor.isAfterLast()) { id = cursor.getInt(0); } cursor.close(); } return id; } private String makePlaylistName() { String template = getString(R.string.new_playlist_name_template); int num = 1; String[] cols = new String[] { MediaStore.Audio.Playlists.NAME }; ContentResolver resolver = getContentResolver(); String whereclause = MediaStore.Audio.Playlists.NAME + " != ''"; Cursor cursor = resolver.query(MediaStore.Audio.Playlists.EXTERNAL_CONTENT_URI, cols, whereclause, null, MediaStore.Audio.Playlists.NAME); if (cursor == null) return null; String suggestedname; suggestedname = String.format(template, num++); // Need to loop until we've made 1 full pass through without finding a // match. Looping more than once shouldn't happen very often, but will // happen if you have playlists named // "New Playlist 1"/10/2/3/4/5/6/7/8/9, where making only one pass would // result in "New Playlist 10" being erroneously picked for the new // name. boolean done = false; while (!done) { done = true; cursor.moveToFirst(); while (!cursor.isAfterLast()) { String playlistname = cursor.getString(0); if (playlistname.compareToIgnoreCase(suggestedname) == 0) { suggestedname = String.format(template, num++); done = false; } cursor.moveToNext(); } } cursor.close(); return suggestedname; }; private String nameForId(long id) { Cursor cursor = mUtils.query(MediaStore.Audio.Playlists.EXTERNAL_CONTENT_URI, new String[] { MediaStore.Audio.Playlists.NAME }, MediaStore.Audio.Playlists._ID + "=?", new String[] { Long.valueOf(id).toString() }, MediaStore.Audio.Playlists.NAME); String name = null; if (cursor != null) { cursor.moveToFirst(); if (!cursor.isAfterLast()) { name = cursor.getString(0); } cursor.close(); } return name; } private void setSaveButton() { String typedname = mPlaylist.getText().toString(); Button button = mPlaylistDialog.getButton(Dialog.BUTTON_POSITIVE); if (button == null) return; if (typedname.trim().length() == 0 || PLAYLIST_NAME_FAVORITES.equals(typedname)) { button.setEnabled(false); } else { button.setEnabled(true); if (idForplaylist(typedname) >= 0 && !mOriginalName.equals(typedname)) { button.setText(R.string.overwrite); } else { button.setText(R.string.save); } } button.invalidate(); } @Override protected void onResume() { super.onResume(); if (mPlaylistDialog != null) { mPlaylistDialog.show(); } } }