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 zeitcoin.wallet.ui; import java.util.concurrent.RejectedExecutionException; import java.util.concurrent.atomic.AtomicReference; import javax.annotation.CheckForNull; import javax.annotation.Nonnull; import zeitcoin.wallet.Constants; import zeitcoin.wallet.WalletApplication; import zeitcoin.wallet.util.BitmapFragment; import zeitcoin.wallet.util.Qr; import zeitcoin.wallet.util.ThrottlingWalletChangeListener; import zeitcoin.wallet.util.WalletUtils; import org.bitcoinj.core.Address; import org.bitcoinj.core.Wallet; import org.bitcoinj.uri.BitcoinURI; import org.bitcoinj.utils.Threading; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import android.app.Activity; import android.app.Fragment; import android.app.LoaderManager; import android.app.LoaderManager.LoaderCallbacks; import android.content.AsyncTaskLoader; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.Loader; import android.graphics.Bitmap; import android.nfc.NdefMessage; import android.nfc.NdefRecord; import android.nfc.NfcAdapter; import android.nfc.NfcEvent; import android.nfc.NfcManager; import android.os.Bundle; import android.support.v4.content.LocalBroadcastManager; import android.text.Spanned; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.widget.ImageView; import zeitcoin.wallet.R; /** * @author Andreas Schildbach */ public final class WalletAddressFragment extends Fragment implements NfcAdapter.CreateNdefMessageCallback { private Activity activity; private WalletApplication application; private LoaderManager loaderManager; @CheckForNull private NfcAdapter nfcAdapter; private ImageView currentAddressQrView; private Bitmap currentAddressQrBitmap = null; private Spanned currentAddressQrLabel = null; private final AtomicReference<String> currentAddressUriRef = new AtomicReference<String>(); private static final int ID_ADDRESS_LOADER = 0; @Override public void onAttach(final Activity activity) { super.onAttach(activity); this.activity = activity; this.application = (WalletApplication) activity.getApplication(); this.loaderManager = getLoaderManager(); final NfcManager nfcManager = (NfcManager) activity.getSystemService(Context.NFC_SERVICE); this.nfcAdapter = nfcManager.getDefaultAdapter(); } @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); if (nfcAdapter != null && nfcAdapter.isEnabled()) nfcAdapter.setNdefPushMessageCallback(this, activity); } @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { final View view = inflater.inflate(R.layout.wallet_address_fragment, container, false); currentAddressQrView = (ImageView) view.findViewById(R.id.bitcoin_address_qr); currentAddressQrView.setOnClickListener(new OnClickListener() { @Override public void onClick(final View v) { handleShowQRCode(); } }); return view; } @Override public void onResume() { super.onResume(); loaderManager.initLoader(ID_ADDRESS_LOADER, null, addressLoaderCallbacks); updateView(); } @Override public void onPause() { loaderManager.destroyLoader(ID_ADDRESS_LOADER); super.onPause(); } private void updateView() { currentAddressQrView.setImageBitmap(currentAddressQrBitmap); } private void handleShowQRCode() { BitmapFragment.show(getFragmentManager(), currentAddressQrBitmap, currentAddressQrLabel); } public static class CurrentAddressLoader extends AsyncTaskLoader<Address> { private LocalBroadcastManager broadcastManager; private final Wallet wallet; private static final Logger log = LoggerFactory.getLogger(WalletBalanceLoader.class); public CurrentAddressLoader(final Context context, @Nonnull final Wallet wallet) { super(context); this.broadcastManager = LocalBroadcastManager.getInstance(context.getApplicationContext()); this.wallet = wallet; } @Override protected void onStartLoading() { super.onStartLoading(); wallet.addEventListener(walletChangeListener, Threading.SAME_THREAD); broadcastManager.registerReceiver(walletChangeReceiver, new IntentFilter(WalletApplication.ACTION_WALLET_CHANGED)); safeForceLoad(); } @Override protected void onStopLoading() { broadcastManager.unregisterReceiver(walletChangeReceiver); wallet.removeEventListener(walletChangeListener); walletChangeListener.removeCallbacks(); super.onStopLoading(); } @Override protected void onReset() { broadcastManager.unregisterReceiver(walletChangeReceiver); wallet.removeEventListener(walletChangeListener); walletChangeListener.removeCallbacks(); super.onReset(); } @Override public Address loadInBackground() { return wallet.currentReceiveAddress(); } private final ThrottlingWalletChangeListener walletChangeListener = new ThrottlingWalletChangeListener() { @Override public void onThrottledWalletChanged() { safeForceLoad(); } }; private final BroadcastReceiver walletChangeReceiver = new BroadcastReceiver() { @Override public void onReceive(final Context context, final Intent intent) { safeForceLoad(); } }; private void safeForceLoad() { try { forceLoad(); } catch (final RejectedExecutionException x) { log.info("rejected execution: " + CurrentAddressLoader.this.toString()); } } } private final LoaderCallbacks<Address> addressLoaderCallbacks = new LoaderManager.LoaderCallbacks<Address>() { private Address lastAddress; @Override public Loader<Address> onCreateLoader(final int id, final Bundle args) { return new CurrentAddressLoader(activity, application.getWallet()); } @Override public void onLoadFinished(final Loader<Address> loader, final Address currentAddress) { if (!currentAddress.equals(lastAddress)) { lastAddress = currentAddress; final String addressStr = BitcoinURI.convertToBitcoinURI(currentAddress, null, null, null); final int size = getResources().getDimensionPixelSize(R.dimen.bitmap_dialog_qr_size); currentAddressQrBitmap = Qr.bitmap(addressStr, size); currentAddressQrLabel = WalletUtils.formatAddress(currentAddress, Constants.ADDRESS_FORMAT_GROUP_SIZE, Constants.ADDRESS_FORMAT_LINE_SIZE); currentAddressUriRef.set(addressStr); updateView(); } } @Override public void onLoaderReset(final Loader<Address> loader) { } }; @Override public NdefMessage createNdefMessage(final NfcEvent event) { final String uri = currentAddressUriRef.get(); if (uri != null) return new NdefMessage(new NdefRecord[] { NdefRecord.createUri(uri) }); else return null; } }