Java tutorial
/* * Copyright 2014 the original author or authors. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package biz.wiz.android.wallet.ui; import java.util.List; import org.bitcoinj.core.Transaction; import org.bitcoinj.core.Wallet; import org.bitcoinj.wallet.DeterministicUpgradeRequiresPassword; import android.app.Activity; import android.app.Fragment; import android.app.FragmentManager; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.Bundle; import android.support.v4.content.LocalBroadcastManager; import com.google.common.util.concurrent.ListenableFuture; import biz.wiz.android.wallet.WalletApplication; import biz.wiz.android.wallet.service.BlockchainService; import biz.wiz.android.wallet.service.BlockchainState; import biz.wiz.android.wallet.ui.send.MaintenanceDialogFragment; /** * @author Andreas Schildbach */ public class MaybeMaintenanceFragment extends Fragment { private static final String FRAGMENT_TAG = MaybeMaintenanceFragment.class.getName(); public static void add(final FragmentManager fm) { Fragment fragment = fm.findFragmentByTag(FRAGMENT_TAG); if (fragment == null) { fragment = new MaybeMaintenanceFragment(); fm.beginTransaction().add(fragment, FRAGMENT_TAG).commit(); } } private Wallet wallet; private LocalBroadcastManager broadcastManager; private boolean dialogWasShown = false; @Override public void onAttach(final Activity activity) { super.onAttach(activity); final WalletApplication application = ((AbstractWalletActivity) activity).getWalletApplication(); this.wallet = application.getWallet(); this.broadcastManager = LocalBroadcastManager.getInstance(activity); } @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); setRetainInstance(true); } @Override public void onResume() { super.onResume(); broadcastManager.registerReceiver(broadcastReceiver, new IntentFilter(BlockchainService.ACTION_BLOCKCHAIN_STATE)); } @Override public void onPause() { broadcastManager.unregisterReceiver(broadcastReceiver); super.onPause(); } private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() { @Override public void onReceive(final Context context, final Intent broadcast) { final BlockchainState blockchainState = BlockchainState.fromIntent(broadcast); if (!dialogWasShown && !blockchainState.replaying && maintenanceRecommended()) { MaintenanceDialogFragment.show(getFragmentManager()); dialogWasShown = true; } } }; private boolean maintenanceRecommended() { try { final ListenableFuture<List<Transaction>> result = wallet.doMaintenance(null, false); return !result.get().isEmpty(); } catch (final DeterministicUpgradeRequiresPassword x) { return true; } catch (final Exception x) { throw new RuntimeException(x); } } }