Java tutorial
/* * Copyright 2011-2014 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 com.bushstar.htmlcoin_android_wallet.ui; import java.math.BigInteger; import javax.annotation.CheckForNull; import android.app.Activity; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.SharedPreferences; import android.content.SharedPreferences.OnSharedPreferenceChangeListener; import android.database.Cursor; import android.net.Uri; import android.os.Build; import android.os.Bundle; import android.support.v4.app.LoaderManager; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.CursorLoader; import android.support.v4.content.Loader; import android.support.v4.widget.ResourceCursorAdapter; import android.support.v4.widget.SearchViewCompat; import android.view.View; import android.widget.ListView; import android.widget.TextView; import com.actionbarsherlock.app.SherlockListFragment; import com.actionbarsherlock.view.ActionMode; import com.actionbarsherlock.view.Menu; import com.actionbarsherlock.view.MenuInflater; import com.actionbarsherlock.view.MenuItem; import com.bushstar.htmlcoinj.core.Wallet; import com.bushstar.htmlcoinj.core.Wallet.BalanceType; import com.bushstar.htmlcoin_android_wallet.Configuration; import com.bushstar.htmlcoin_android_wallet.Constants; import com.bushstar.htmlcoin_android_wallet.ExchangeRatesProvider; import com.bushstar.htmlcoin_android_wallet.ExchangeRatesProvider.ExchangeRate; import com.bushstar.htmlcoin_android_wallet.WalletApplication; import com.bushstar.htmlcoin_android_wallet.service.BlockchainService; import com.bushstar.htmlcoin_android_wallet.util.GenericUtils; import com.bushstar.htmlcoin_android_wallet.util.WalletUtils; import com.bushstar.htmlcoin_android_wallet.util.WholeStringBuilder; import com.bushstar.htmlcoin_android_wallet.R; /** * @author Andreas Schildbach */ public final class ExchangeRatesFragment extends SherlockListFragment implements OnSharedPreferenceChangeListener { private AbstractWalletActivity activity; private WalletApplication application; private Configuration config; private Wallet wallet; private Uri contentUri; private LoaderManager loaderManager; private ExchangeRatesAdapter adapter; private String query = null; private BigInteger balance = null; private boolean replaying = false; @CheckForNull private String defaultCurrency = null; private static final int ID_BALANCE_LOADER = 0; private static final int ID_RATE_LOADER = 1; @Override public void onAttach(final Activity activity) { super.onAttach(activity); this.activity = (AbstractWalletActivity) activity; this.application = (WalletApplication) activity.getApplication(); this.config = application.getConfiguration(); this.wallet = application.getWallet(); this.contentUri = ExchangeRatesProvider.contentUri(activity.getPackageName()); this.loaderManager = getLoaderManager(); } @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); setRetainInstance(true); setHasOptionsMenu(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB); adapter = new ExchangeRatesAdapter(activity); setListAdapter(adapter); loaderManager.initLoader(ID_RATE_LOADER, null, rateLoaderCallbacks); defaultCurrency = config.getExchangeCurrencyCode(); config.registerOnSharedPreferenceChangeListener(this); } @Override public void onViewCreated(final View view, final Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); getListView().setFastScrollEnabled(true); updateEmptyText(); } @Override public void onResume() { super.onResume(); activity.registerReceiver(broadcastReceiver, new IntentFilter(BlockchainService.ACTION_BLOCKCHAIN_STATE)); loaderManager.initLoader(ID_BALANCE_LOADER, null, balanceLoaderCallbacks); updateView(); } @Override public void onPause() { loaderManager.destroyLoader(ID_BALANCE_LOADER); activity.unregisterReceiver(broadcastReceiver); super.onPause(); } @Override public void onDestroy() { config.unregisterOnSharedPreferenceChangeListener(this); loaderManager.destroyLoader(ID_RATE_LOADER); super.onDestroy(); } @Override public void onCreateOptionsMenu(final Menu menu, final MenuInflater inflater) { inflater.inflate(R.menu.exchange_rates_fragment_options, menu); final View searchView = menu.findItem(R.id.exchange_rates_options_search).getActionView(); if (searchView != null) { SearchViewCompat.setOnQueryTextListener(searchView, new SearchViewCompat.OnQueryTextListenerCompat() { @Override public boolean onQueryTextChange(final String newText) { query = newText.trim(); if (query.isEmpty()) query = null; updateEmptyText(); getLoaderManager().restartLoader(ID_RATE_LOADER, null, rateLoaderCallbacks); return true; } @Override public boolean onQueryTextSubmit(final String query) { searchView.clearFocus(); return true; } }); } super.onCreateOptionsMenu(menu, inflater); } @Override public void onListItemClick(final ListView l, final View v, final int position, final long id) { final Cursor cursor = (Cursor) adapter.getItem(position); final ExchangeRate exchangeRate = ExchangeRatesProvider.getExchangeRate(cursor); activity.startActionMode(new ActionMode.Callback() { @Override public boolean onCreateActionMode(final ActionMode mode, final Menu menu) { final MenuInflater inflater = mode.getMenuInflater(); inflater.inflate(R.menu.exchange_rates_context, menu); return true; } @Override public boolean onPrepareActionMode(final ActionMode mode, final Menu menu) { mode.setTitle(exchangeRate.currencyCode); mode.setSubtitle(getString(R.string.exchange_rates_fragment_source, exchangeRate.source)); return true; } @Override public boolean onActionItemClicked(final ActionMode mode, final MenuItem item) { switch (item.getItemId()) { case R.id.exchange_rates_context_set_as_default: handleSetAsDefault(exchangeRate.currencyCode); mode.finish(); return true; } return false; } @Override public void onDestroyActionMode(final ActionMode mode) { } private void handleSetAsDefault(final String currencyCode) { config.setExchangeCurrencyCode(currencyCode); } }); } @Override public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key) { if (Configuration.PREFS_KEY_EXCHANGE_CURRENCY.equals(key) || Configuration.PREFS_KEY_HTML5_PRECISION.equals(key)) { defaultCurrency = config.getExchangeCurrencyCode(); updateView(); } } private void updateView() { balance = application.getWallet().getBalance(BalanceType.ESTIMATED); if (adapter != null) { final int HTML5Shift = config.getHTML5Shift(); final BigInteger base = HTML5Shift == 0 ? GenericUtils.ONE_HTML5 : GenericUtils.ONE_MHTML5; adapter.setRateBase(base); } } private void updateEmptyText() { setEmptyText(WholeStringBuilder.bold(getString(query != null ? R.string.exchange_rates_fragment_empty_search : R.string.exchange_rates_fragment_empty_text))); } private final BlockchainBroadcastReceiver broadcastReceiver = new BlockchainBroadcastReceiver(); private final class BlockchainBroadcastReceiver extends BroadcastReceiver { @Override public void onReceive(final Context context, final Intent intent) { replaying = intent.getBooleanExtra(BlockchainService.ACTION_BLOCKCHAIN_STATE_REPLAYING, false); updateView(); } } private final LoaderCallbacks<Cursor> rateLoaderCallbacks = new LoaderManager.LoaderCallbacks<Cursor>() { @Override public Loader<Cursor> onCreateLoader(final int id, final Bundle args) { if (query == null) return new CursorLoader(activity, contentUri, null, null, null, null); else return new CursorLoader(activity, contentUri, null, ExchangeRatesProvider.QUERY_PARAM_Q, new String[] { query }, null); } @Override public void onLoadFinished(final Loader<Cursor> loader, final Cursor data) { final Cursor oldCursor = adapter.swapCursor(data); if (data != null && oldCursor == null && defaultCurrency != null) { final int defaultCurrencyPosition = findCurrencyCode(data, defaultCurrency); if (defaultCurrencyPosition >= 0) getListView().setSelection(defaultCurrencyPosition); // scroll to selection } } @Override public void onLoaderReset(final Loader<Cursor> loader) { } private int findCurrencyCode(final Cursor cursor, final String currencyCode) { final int currencyCodeColumn = cursor.getColumnIndexOrThrow(ExchangeRatesProvider.KEY_CURRENCY_CODE); cursor.moveToPosition(-1); while (cursor.moveToNext()) { if (cursor.getString(currencyCodeColumn).equals(currencyCode)) return cursor.getPosition(); } return -1; } }; private final LoaderCallbacks<BigInteger> balanceLoaderCallbacks = new LoaderManager.LoaderCallbacks<BigInteger>() { @Override public Loader<BigInteger> onCreateLoader(final int id, final Bundle args) { return new WalletBalanceLoader(activity, wallet); } @Override public void onLoadFinished(final Loader<BigInteger> loader, final BigInteger balance) { ExchangeRatesFragment.this.balance = balance; updateView(); } @Override public void onLoaderReset(final Loader<BigInteger> loader) { } }; private final class ExchangeRatesAdapter extends ResourceCursorAdapter { private BigInteger rateBase = GenericUtils.ONE_HTML5; private ExchangeRatesAdapter(final Context context) { super(context, R.layout.exchange_rate_row, null, true); } public void setRateBase(final BigInteger rateBase) { this.rateBase = rateBase; notifyDataSetChanged(); } @Override public void bindView(final View view, final Context context, final Cursor cursor) { final ExchangeRate exchangeRate = ExchangeRatesProvider.getExchangeRate(cursor); final boolean isDefaultCurrency = exchangeRate.currencyCode.equals(defaultCurrency); view.setBackgroundResource(isDefaultCurrency ? R.color.bg_list_selected : R.color.bg_list); final View defaultView = view.findViewById(R.id.exchange_rate_row_default); defaultView.setVisibility(isDefaultCurrency ? View.VISIBLE : View.INVISIBLE); final TextView currencyCodeView = (TextView) view.findViewById(R.id.exchange_rate_row_currency_code); currencyCodeView.setText(exchangeRate.currencyCode); final CurrencyTextView rateView = (CurrencyTextView) view.findViewById(R.id.exchange_rate_row_rate); rateView.setPrecision(Constants.LOCAL_PRECISION, 0); rateView.setAmount(WalletUtils.localValue(rateBase, exchangeRate.rate)); final CurrencyTextView walletView = (CurrencyTextView) view .findViewById(R.id.exchange_rate_row_balance); walletView.setPrecision(Constants.LOCAL_PRECISION, 0); if (!replaying) { walletView.setAmount(WalletUtils.localValue(balance, exchangeRate.rate)); walletView.setStrikeThru(Constants.TEST); } else { walletView.setText("n/a"); walletView.setStrikeThru(false); } walletView.setTextColor(getResources().getColor(R.color.fg_less_significant)); } } }