Java tutorial
/* * Copyright (C) 2015 Square, Inc. * * 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.example.sqlbrite.todo.ui; import android.app.Activity; import android.database.Cursor; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.support.v4.view.MenuItemCompat; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.ListView; import butterknife.BindView; import butterknife.ButterKnife; import com.example.sqlbrite.todo.R; import com.example.sqlbrite.todo.TodoApp; import com.example.sqlbrite.todo.db.Db; import com.example.sqlbrite.todo.db.TodoItem; import com.example.sqlbrite.todo.db.TodoList; import com.jakewharton.rxbinding.widget.AdapterViewItemClickEvent; import com.jakewharton.rxbinding.widget.RxAdapterView; import com.squareup.sqlbrite.BriteDatabase; import javax.inject.Inject; import rx.Observable; import rx.android.schedulers.AndroidSchedulers; import rx.functions.Action1; import rx.functions.Func1; import rx.functions.Func2; import rx.schedulers.Schedulers; import rx.subscriptions.CompositeSubscription; import static android.support.v4.view.MenuItemCompat.SHOW_AS_ACTION_IF_ROOM; import static android.support.v4.view.MenuItemCompat.SHOW_AS_ACTION_WITH_TEXT; import static com.squareup.sqlbrite.SqlBrite.Query; public final class ItemsFragment extends Fragment { private static final String KEY_LIST_ID = "list_id"; private static final String LIST_QUERY = "SELECT * FROM " + TodoItem.TABLE + " WHERE " + TodoItem.LIST_ID + " = ? ORDER BY " + TodoItem.COMPLETE + " ASC"; private static final String COUNT_QUERY = "SELECT COUNT(*) FROM " + TodoItem.TABLE + " WHERE " + TodoItem.COMPLETE + " = " + Db.BOOLEAN_FALSE + " AND " + TodoItem.LIST_ID + " = ?"; private static final String TITLE_QUERY = "SELECT " + TodoList.NAME + " FROM " + TodoList.TABLE + " WHERE " + TodoList.ID + " = ?"; public interface Listener { void onNewItemClicked(long listId); } public static ItemsFragment newInstance(long listId) { Bundle arguments = new Bundle(); arguments.putLong(KEY_LIST_ID, listId); ItemsFragment fragment = new ItemsFragment(); fragment.setArguments(arguments); return fragment; } @Inject BriteDatabase db; @BindView(android.R.id.list) ListView listView; @BindView(android.R.id.empty) View emptyView; private Listener listener; private ItemsAdapter adapter; private CompositeSubscription subscriptions; private long getListId() { return getArguments().getLong(KEY_LIST_ID); } @Override public void onAttach(Activity activity) { if (!(activity instanceof Listener)) { throw new IllegalStateException("Activity must implement fragment Listener."); } super.onAttach(activity); TodoApp.getComponent(activity).inject(this); setHasOptionsMenu(true); listener = (Listener) activity; adapter = new ItemsAdapter(activity); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { super.onCreateOptionsMenu(menu, inflater); MenuItem item = menu.add(R.string.new_item) .setOnMenuItemClickListener(new MenuItem.OnMenuItemClickListener() { @Override public boolean onMenuItemClick(MenuItem item) { listener.onNewItemClicked(getListId()); return true; } }); MenuItemCompat.setShowAsAction(item, SHOW_AS_ACTION_IF_ROOM | SHOW_AS_ACTION_WITH_TEXT); } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { return inflater.inflate(R.layout.items, container, false); } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); ButterKnife.bind(this, view); listView.setEmptyView(emptyView); listView.setAdapter(adapter); RxAdapterView.itemClickEvents(listView) // .observeOn(Schedulers.io()).subscribe(new Action1<AdapterViewItemClickEvent>() { @Override public void call(AdapterViewItemClickEvent event) { boolean newValue = !adapter.getItem(event.position()).complete(); db.update(TodoItem.TABLE, new TodoItem.Builder().complete(newValue).build(), TodoItem.ID + " = ?", String.valueOf(event.id())); } }); } @Override public void onResume() { super.onResume(); String listId = String.valueOf(getListId()); subscriptions = new CompositeSubscription(); Observable<Integer> itemCount = db.createQuery(TodoItem.TABLE, COUNT_QUERY, listId) // .map(new Func1<Query, Integer>() { @Override public Integer call(Query query) { Cursor cursor = query.run(); try { if (!cursor.moveToNext()) { throw new AssertionError("No rows"); } return cursor.getInt(0); } finally { cursor.close(); } } }); Observable<String> listName = db.createQuery(TodoList.TABLE, TITLE_QUERY, listId) .map(new Func1<Query, String>() { @Override public String call(Query query) { Cursor cursor = query.run(); try { if (!cursor.moveToNext()) { throw new AssertionError("No rows"); } return cursor.getString(0); } finally { cursor.close(); } } }); subscriptions.add(Observable.combineLatest(listName, itemCount, new Func2<String, Integer, String>() { @Override public String call(String listName, Integer itemCount) { return listName + " (" + itemCount + ")"; } }).observeOn(AndroidSchedulers.mainThread()).subscribe(new Action1<String>() { @Override public void call(String title) { getActivity().setTitle(title); } })); subscriptions.add(db.createQuery(TodoItem.TABLE, LIST_QUERY, listId).mapToList(TodoItem.MAPPER) .observeOn(AndroidSchedulers.mainThread()).subscribe(adapter)); } @Override public void onPause() { super.onPause(); subscriptions.unsubscribe(); } }