| /* |
| * Copyright (C) 2017 The Android Open Source 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 androidx.room.integration.testapp; |
| |
| import android.app.Application; |
| |
| import androidx.annotation.WorkerThread; |
| import androidx.arch.core.executor.ArchTaskExecutor; |
| import androidx.lifecycle.AndroidViewModel; |
| import androidx.lifecycle.LiveData; |
| import androidx.paging.DataSource; |
| import androidx.paging.LivePagedListBuilder; |
| import androidx.paging.PagedList; |
| import androidx.paging.RxPagedListBuilder; |
| import androidx.room.Room; |
| import androidx.room.integration.testapp.database.Customer; |
| import androidx.room.integration.testapp.database.LastNameAscCustomerDataSource; |
| import androidx.room.integration.testapp.database.SampleDatabase; |
| |
| import java.util.UUID; |
| |
| import io.reactivex.BackpressureStrategy; |
| import io.reactivex.Flowable; |
| |
| /** |
| * Sample database-backed view model of Customers |
| */ |
| public class CustomerViewModel extends AndroidViewModel { |
| private SampleDatabase mDatabase; |
| private LiveData<PagedList<Customer>> mLiveCustomerList; |
| |
| public CustomerViewModel(Application application) { |
| super(application); |
| createDb(); |
| } |
| |
| private void createDb() { |
| mDatabase = Room.databaseBuilder(this.getApplication(), |
| SampleDatabase.class, "customerDatabase").build(); |
| |
| ArchTaskExecutor.getInstance().executeOnDiskIO(() -> { |
| // fill with some simple data |
| int customerCount = mDatabase.getCustomerDao().countCustomers(); |
| if (customerCount == 0) { |
| Customer[] initialCustomers = new Customer[10]; |
| for (int i = 0; i < 10; i++) { |
| initialCustomers[i] = createCustomer(); |
| } |
| mDatabase.getCustomerDao().insertAll(initialCustomers); |
| } |
| |
| }); |
| } |
| |
| @WorkerThread |
| private Customer createCustomer() { |
| Customer customer = new Customer(); |
| customer.setName(UUID.randomUUID().toString()); |
| customer.setLastName(UUID.randomUUID().toString()); |
| return customer; |
| } |
| |
| void insertCustomer() { |
| ArchTaskExecutor.getInstance().executeOnDiskIO( |
| () -> mDatabase.getCustomerDao().insert(createCustomer())); |
| } |
| |
| void clearAllCustomers() { |
| ArchTaskExecutor.getInstance().executeOnDiskIO( |
| () -> mDatabase.getCustomerDao().removeAll()); |
| } |
| |
| private static <K> LiveData<PagedList<Customer>> getLivePagedList( |
| K initialLoadKey, DataSource.Factory<K, Customer> dataSourceFactory) { |
| PagedList.Config config = new PagedList.Config.Builder() |
| .setPageSize(10) |
| .setEnablePlaceholders(false) |
| .build(); |
| return new LivePagedListBuilder<>(dataSourceFactory, config) |
| .setInitialLoadKey(initialLoadKey) |
| .build(); |
| } |
| |
| private static <K> Flowable<PagedList<Customer>> getPagedListFlowable( |
| DataSource.Factory<K, Customer> dataSourceFactory) { |
| PagedList.Config config = new PagedList.Config.Builder() |
| .setPageSize(10) |
| .setEnablePlaceholders(false) |
| .build(); |
| return new RxPagedListBuilder<>(dataSourceFactory, config) |
| .buildFlowable(BackpressureStrategy.LATEST); |
| } |
| |
| Flowable<PagedList<Customer>> getPagedListFlowable() { |
| return getPagedListFlowable(mDatabase.getCustomerDao().loadPagedAgeOrder()); |
| } |
| |
| LiveData<PagedList<Customer>> getLivePagedList(int position) { |
| if (mLiveCustomerList == null) { |
| mLiveCustomerList = |
| getLivePagedList(position, mDatabase.getCustomerDao().loadPagedAgeOrder()); |
| } |
| return mLiveCustomerList; |
| } |
| |
| LiveData<PagedList<Customer>> getLivePagedList(String key) { |
| if (mLiveCustomerList == null) { |
| mLiveCustomerList = |
| getLivePagedList(key, LastNameAscCustomerDataSource.factory(mDatabase)); |
| } |
| return mLiveCustomerList; |
| } |
| } |