Java tutorial
/* * Copyright 2013-2014 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 zeitcoin.wallet.ui; import java.util.ArrayList; import java.util.Collection; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.concurrent.RejectedExecutionException; import javax.annotation.Nonnull; import zeitcoin.wallet.Configuration; import zeitcoin.wallet.Constants; import zeitcoin.wallet.WalletApplication; import zeitcoin.wallet.service.BlockchainService; import zeitcoin.wallet.service.BlockchainServiceImpl; import zeitcoin.wallet.util.WalletUtils; import org.bitcoinj.core.Block; import org.bitcoinj.core.Sha256Hash; import org.bitcoinj.core.StoredBlock; import org.bitcoinj.core.Transaction; import org.bitcoinj.core.Wallet; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import android.app.Activity; import android.app.ListFragment; import android.app.LoaderManager; import android.app.LoaderManager.LoaderCallbacks; import android.content.AsyncTaskLoader; import android.content.BroadcastReceiver; import android.content.ComponentName; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.Loader; import android.content.ServiceConnection; import android.net.Uri; import android.os.Bundle; import android.os.IBinder; import android.support.v4.content.LocalBroadcastManager; import android.text.format.DateUtils; import android.view.ActionMode; 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.BaseAdapter; import android.widget.ListView; import android.widget.TextView; import zeitcoin.wallet.R; /** * @author Andreas Schildbach */ public final class BlockListFragment extends ListFragment { private AbstractWalletActivity activity; private WalletApplication application; private Configuration config; private Wallet wallet; private LoaderManager loaderManager; private BlockchainService service; private BlockListAdapter adapter; private Set<Transaction> transactions; private static final int ID_BLOCK_LOADER = 0; private static final int ID_TRANSACTION_LOADER = 1; private static final int MAX_BLOCKS = 32; private static final Logger log = LoggerFactory.getLogger(BlockListFragment.class); @Override public void onAttach(final Activity activity) { super.onAttach(activity); this.activity = (AbstractWalletActivity) activity; this.application = this.activity.getWalletApplication(); this.config = application.getConfiguration(); this.wallet = application.getWallet(); this.loaderManager = getLoaderManager(); } @Override public void onActivityCreated(final Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); activity.bindService(new Intent(activity, BlockchainServiceImpl.class), serviceConnection, Context.BIND_AUTO_CREATE); } @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); adapter = new BlockListAdapter(); setListAdapter(adapter); } private boolean resumed = false; @Override public void onResume() { super.onResume(); activity.registerReceiver(tickReceiver, new IntentFilter(Intent.ACTION_TIME_TICK)); loaderManager.initLoader(ID_TRANSACTION_LOADER, null, transactionLoaderCallbacks); adapter.notifyDataSetChanged(); resumed = true; } @Override public void onPause() { // workaround: under high load, it can happen that onPause() is called twice (recursively via destroyLoader) if (resumed) { resumed = false; loaderManager.destroyLoader(ID_TRANSACTION_LOADER); activity.unregisterReceiver(tickReceiver); } else { log.warn("onPause() called without onResume(), appending stack trace", new RuntimeException()); } super.onPause(); } @Override public void onDestroy() { activity.unbindService(serviceConnection); super.onDestroy(); } @Override public void onListItemClick(final ListView l, final View v, final int position, final long id) { final StoredBlock storedBlock = adapter.getItem(position); activity.startActionMode(new ActionMode.Callback() { @Override public boolean onCreateActionMode(final ActionMode mode, final Menu menu) { final MenuInflater inflater = mode.getMenuInflater(); inflater.inflate(R.menu.blocks_context, menu); return true; } @Override public boolean onPrepareActionMode(final ActionMode mode, final Menu menu) { mode.setTitle(Integer.toString(storedBlock.getHeight())); mode.setSubtitle(storedBlock.getHeader().getHashAsString()); return true; } @Override public boolean onActionItemClicked(final ActionMode mode, final MenuItem item) { switch (item.getItemId()) { case R.id.blocks_context_browse: startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse( Constants.EXPLORE_BASE_URL + "block/" + storedBlock.getHeader().getHashAsString()))); mode.finish(); return true; } return false; } @Override public void onDestroyActionMode(final ActionMode mode) { } }); } private final ServiceConnection serviceConnection = new ServiceConnection() { @Override public void onServiceConnected(final ComponentName name, final IBinder binder) { service = ((BlockchainServiceImpl.LocalBinder) binder).getService(); loaderManager.initLoader(ID_BLOCK_LOADER, null, blockLoaderCallbacks); } @Override public void onServiceDisconnected(final ComponentName name) { loaderManager.destroyLoader(ID_BLOCK_LOADER); service = null; } }; private final BroadcastReceiver tickReceiver = new BroadcastReceiver() { @Override public void onReceive(final Context context, final Intent intent) { adapter.notifyDataSetChanged(); } }; private final class BlockListAdapter extends BaseAdapter { private static final int ROW_BASE_CHILD_COUNT = 2; private static final int ROW_INSERT_INDEX = 1; private final TransactionsListAdapter transactionsAdapter = new TransactionsListAdapter(activity, wallet, application.maxConnectedPeers(), false); private final LayoutInflater inflater = LayoutInflater.from(activity); private final List<StoredBlock> blocks = new ArrayList<StoredBlock>(MAX_BLOCKS); public void clear() { blocks.clear(); adapter.notifyDataSetChanged(); } public void replace(@Nonnull final Collection<StoredBlock> blocks) { this.blocks.clear(); this.blocks.addAll(blocks); notifyDataSetChanged(); } @Override public int getCount() { return blocks.size(); } @Override public StoredBlock getItem(final int position) { return blocks.get(position); } @Override public long getItemId(final int position) { return WalletUtils.longHash(blocks.get(position).getHeader().getHash()); } @Override public boolean hasStableIds() { return true; } @Override public View getView(final int position, final View convertView, final ViewGroup parent) { final ViewGroup row; if (convertView == null) row = (ViewGroup) inflater.inflate(R.layout.block_row, null); else row = (ViewGroup) convertView; final StoredBlock storedBlock = getItem(position); final Block header = storedBlock.getHeader(); final TextView rowHeight = (TextView) row.findViewById(R.id.block_list_row_height); final int height = storedBlock.getHeight(); rowHeight.setText(Integer.toString(height)); final TextView rowTime = (TextView) row.findViewById(R.id.block_list_row_time); final long timeMs = header.getTimeSeconds() * DateUtils.SECOND_IN_MILLIS; if (timeMs < System.currentTimeMillis()) rowTime.setText(DateUtils.getRelativeDateTimeString(activity, timeMs, DateUtils.MINUTE_IN_MILLIS, DateUtils.WEEK_IN_MILLIS, 0)); else rowTime.setText(R.string.block_row_now); final TextView rowHash = (TextView) row.findViewById(R.id.block_list_row_hash); rowHash.setText(WalletUtils.formatHash(null, header.getHashAsString(), 8, 0, ' ')); final int transactionChildCount = row.getChildCount() - ROW_BASE_CHILD_COUNT; int iTransactionView = 0; if (transactions != null) { transactionsAdapter.setFormat(config.getFormat()); for (final Transaction tx : transactions) { if (tx.getAppearsInHashes().containsKey(header.getHash())) { final View view; if (iTransactionView < transactionChildCount) { view = row.getChildAt(ROW_INSERT_INDEX + iTransactionView); } else { view = inflater.inflate(R.layout.transaction_row_oneline, null); row.addView(view, ROW_INSERT_INDEX + iTransactionView); } transactionsAdapter.bindView(view, tx); iTransactionView++; } } } final int leftoverTransactionViews = transactionChildCount - iTransactionView; if (leftoverTransactionViews > 0) row.removeViews(ROW_INSERT_INDEX + iTransactionView, leftoverTransactionViews); return row; } } private static class BlockLoader extends AsyncTaskLoader<List<StoredBlock>> { private LocalBroadcastManager broadcastManager; private BlockchainService service; private BlockLoader(final Context context, final BlockchainService service) { super(context); this.broadcastManager = LocalBroadcastManager.getInstance(context.getApplicationContext()); this.service = service; } @Override protected void onStartLoading() { super.onStartLoading(); broadcastManager.registerReceiver(broadcastReceiver, new IntentFilter(BlockchainService.ACTION_BLOCKCHAIN_STATE)); forceLoad(); } @Override protected void onStopLoading() { broadcastManager.unregisterReceiver(broadcastReceiver); super.onStopLoading(); } @Override public List<StoredBlock> loadInBackground() { return service.getRecentBlocks(MAX_BLOCKS); } private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() { @Override public void onReceive(final Context context, final Intent intent) { try { forceLoad(); } catch (final RejectedExecutionException x) { log.info("rejected execution: " + BlockLoader.this.toString()); } } }; } private final LoaderCallbacks<List<StoredBlock>> blockLoaderCallbacks = new LoaderCallbacks<List<StoredBlock>>() { @Override public Loader<List<StoredBlock>> onCreateLoader(final int id, final Bundle args) { return new BlockLoader(activity, service); } @Override public void onLoadFinished(final Loader<List<StoredBlock>> loader, final List<StoredBlock> blocks) { adapter.replace(blocks); final Loader<Set<Transaction>> transactionLoader = loaderManager.getLoader(ID_TRANSACTION_LOADER); if (transactionLoader != null && transactionLoader.isStarted()) transactionLoader.forceLoad(); } @Override public void onLoaderReset(final Loader<List<StoredBlock>> loader) { adapter.clear(); } }; private static class TransactionsLoader extends AsyncTaskLoader<Set<Transaction>> { private final Wallet wallet; private TransactionsLoader(final Context context, final Wallet wallet) { super(context); this.wallet = wallet; } @Override public Set<Transaction> loadInBackground() { final Set<Transaction> transactions = wallet.getTransactions(true); final Set<Transaction> filteredTransactions = new HashSet<Transaction>(transactions.size()); for (final Transaction tx : transactions) { final Map<Sha256Hash, Integer> appearsIn = tx.getAppearsInHashes(); if (appearsIn != null && !appearsIn.isEmpty()) // TODO filter by updateTime filteredTransactions.add(tx); } return filteredTransactions; } } private final LoaderCallbacks<Set<Transaction>> transactionLoaderCallbacks = new LoaderCallbacks<Set<Transaction>>() { @Override public Loader<Set<Transaction>> onCreateLoader(final int id, final Bundle args) { return new TransactionsLoader(activity, wallet); } @Override public void onLoadFinished(final Loader<Set<Transaction>> loader, final Set<Transaction> transactions) { BlockListFragment.this.transactions = transactions; adapter.notifyDataSetChanged(); } @Override public void onLoaderReset(final Loader<Set<Transaction>> loader) { BlockListFragment.this.transactions.clear(); // be nice BlockListFragment.this.transactions = null; adapter.notifyDataSetChanged(); } }; }