Java tutorial
/* * Copyright 2014-2015 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 de.schildbach.wallet.ui.send; import java.util.Collections; import java.util.List; import javax.annotation.Nullable; import org.bitcoinj.core.Coin; import org.bitcoinj.core.Transaction; import org.bitcoinj.crypto.KeyCrypterException; import org.bitcoinj.utils.MonetaryFormat; import org.bitcoinj.wallet.DeterministicUpgradeRequiresPassword; import org.bitcoinj.wallet.Wallet; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.spongycastle.crypto.params.KeyParameter; import com.google.common.util.concurrent.ListenableFuture; import de.schildbach.wallet.Constants; import de.schildbach.wallet.WalletApplication; import de.schildbach.wallet.ui.AbstractWalletActivity; import org.dash.wallet.common.ui.DialogBuilder; import de.schildbach.wallet_test.R; import android.app.Activity; import android.app.Dialog; import android.content.DialogInterface; import android.content.DialogInterface.OnShowListener; import android.graphics.Typeface; import android.os.Bundle; import android.os.Handler; import android.os.HandlerThread; import android.os.Process; import android.support.v4.app.DialogFragment; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v7.app.AlertDialog; import android.text.Editable; import android.text.TextWatcher; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; /** * @author Andreas Schildbach */ public class MaintenanceDialogFragment extends DialogFragment { private static final String FRAGMENT_TAG = MaintenanceDialogFragment.class.getName(); public static void show(final FragmentManager fm) { Fragment fragment = fm.findFragmentByTag(FRAGMENT_TAG); if (fragment == null) { fragment = new MaintenanceDialogFragment(); fm.beginTransaction().add(fragment, FRAGMENT_TAG).commit(); } } private AbstractWalletActivity activity; private WalletApplication application; private Wallet wallet; @Nullable private AlertDialog dialog; private View passwordGroup; private EditText passwordView; private View badPasswordView; private Button positiveButton, negativeButton; private Handler handler = new Handler(); private HandlerThread backgroundThread; private Handler backgroundHandler; private enum State { INPUT, DECRYPTING, DONE } private State state = State.INPUT; private static final Logger log = LoggerFactory.getLogger(MaintenanceDialogFragment.class); @Override public void onAttach(final Activity activity) { super.onAttach(activity); this.activity = (AbstractWalletActivity) activity; this.application = (WalletApplication) activity.getApplication(); this.wallet = application.getWallet(); } @Override public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); backgroundThread = new HandlerThread("backgroundThread", Process.THREAD_PRIORITY_BACKGROUND); backgroundThread.start(); backgroundHandler = new Handler(backgroundThread.getLooper()); } @Override public Dialog onCreateDialog(final Bundle savedInstanceState) { final View view = LayoutInflater.from(activity).inflate(R.layout.maintenance_dialog, null); Coin value = Coin.ZERO; Coin fee = Coin.ZERO; for (final Transaction tx : determineMaintenanceTransactions()) { value = value.add(tx.getValueSentFromMe(wallet)); fee = fee.add(tx.getFee()); } final TextView messageView = (TextView) view.findViewById(R.id.maintenance_dialog_message); final MonetaryFormat format = application.getConfiguration().getFormat(); messageView .setText(getString(R.string.maintenance_dialog_message, format.format(value), format.format(fee))); passwordGroup = view.findViewById(R.id.maintenance_dialog_password_group); passwordView = (EditText) view.findViewById(R.id.maintenance_dialog_password); passwordView.setText(null); badPasswordView = view.findViewById(R.id.maintenance_dialog_bad_password); final DialogBuilder builder = new DialogBuilder(activity); builder.setTitle(R.string.maintenance_dialog_title); builder.setView(view); builder.setPositiveButton(R.string.maintenance_dialog_button_move, null); // dummy, just to make it // show builder.setNegativeButton(R.string.button_dismiss, null); builder.setCancelable(false); final AlertDialog dialog = builder.create(); dialog.setCanceledOnTouchOutside(false); dialog.setOnShowListener(new OnShowListener() { @Override public void onShow(final DialogInterface d) { positiveButton = dialog.getButton(DialogInterface.BUTTON_POSITIVE); negativeButton = dialog.getButton(DialogInterface.BUTTON_NEGATIVE); positiveButton.setTypeface(Typeface.DEFAULT_BOLD); positiveButton.setOnClickListener(new OnClickListener() { @Override public void onClick(final View v) { log.info("user decided to do maintenance"); handleGo(); } }); negativeButton.setOnClickListener(new OnClickListener() { @Override public void onClick(final View v) { log.info("user decided to dismiss"); dismiss(); } }); passwordView.addTextChangedListener(textWatcher); MaintenanceDialogFragment.this.dialog = dialog; updateView(); } }); log.info("showing maintenance dialog"); return dialog; } @Override public void onResume() { super.onResume(); updateView(); } @Override public void onDismiss(final DialogInterface dialog) { this.dialog = null; wipePasswords(); super.onDismiss(dialog); } @Override public void onDestroy() { backgroundThread.getLooper().quit(); super.onDestroy(); } private void handleGo() { state = State.DECRYPTING; updateView(); if (wallet.isEncrypted()) { new DeriveKeyTask(backgroundHandler, application.scryptIterationsTarget()) { @Override protected void onSuccess(final KeyParameter encryptionKey, final boolean wasChanged) { if (wasChanged) application.backupWallet(); doMaintenance(encryptionKey); } }.deriveKey(wallet, passwordView.getText().toString().trim()); updateView(); } else { doMaintenance(null); } } private void doMaintenance(final KeyParameter encryptionKey) { backgroundHandler.post(new Runnable() { @Override public void run() { org.bitcoinj.core.Context.propagate(Constants.CONTEXT); try { wallet.doMaintenance(encryptionKey, true); handler.post(new Runnable() { @Override public void run() { state = State.DONE; updateView(); delayedDismiss(); } }); } catch (final KeyCrypterException x) { handler.post(new Runnable() { @Override public void run() { badPasswordView.setVisibility(View.VISIBLE); state = State.INPUT; updateView(); passwordView.requestFocus(); log.info("bad spending password"); } }); } } }); } private void delayedDismiss() { handler.postDelayed(new Runnable() { @Override public void run() { dismiss(); } }, 2000); } private void wipePasswords() { passwordView.setText(null); } private void updateView() { if (dialog == null) return; final boolean needsPassword = wallet.isEncrypted(); passwordGroup.setVisibility(needsPassword ? View.VISIBLE : View.GONE); if (state == State.INPUT) { positiveButton.setText(R.string.maintenance_dialog_button_move); positiveButton.setEnabled(!needsPassword || passwordView.getText().toString().trim().length() > 0); negativeButton.setEnabled(true); } else if (state == State.DECRYPTING) { positiveButton.setText(R.string.maintenance_dialog_state_decrypting); positiveButton.setEnabled(false); negativeButton.setEnabled(false); } else if (state == State.DONE) { positiveButton.setText(R.string.maintenance_dialog_state_done); positiveButton.setEnabled(false); negativeButton.setEnabled(false); } } private List<Transaction> determineMaintenanceTransactions() { try { final ListenableFuture<List<Transaction>> result = wallet.doMaintenance(null, false); return result.get(); } catch (final DeterministicUpgradeRequiresPassword x) { return Collections.emptyList(); } catch (final Exception x) { throw new RuntimeException(x); } } private final TextWatcher textWatcher = new TextWatcher() { @Override public void onTextChanged(final CharSequence s, final int start, final int before, final int count) { badPasswordView.setVisibility(View.INVISIBLE); updateView(); } @Override public void beforeTextChanged(final CharSequence s, final int start, final int count, final int after) { } @Override public void afterTextChanged(final Editable s) { } }; }