com.kncwallet.wallet.ui.ExchangeRatesFragment.java Source code

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Here is the source code for com.kncwallet.wallet.ui.ExchangeRatesFragment.java

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/*
 * 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.kncwallet.wallet.ui;

import java.math.BigInteger;
import java.util.Currency;
import java.util.Locale;

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.os.Bundle;
import android.preference.PreferenceManager;
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.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.google.bitcoin.core.Wallet;
import com.google.bitcoin.core.Wallet.BalanceType;
import com.kncwallet.wallet.Constants;
import com.kncwallet.wallet.ExchangeRatesProvider;
import com.kncwallet.wallet.WalletApplication;
import com.kncwallet.wallet.ExchangeRatesProvider.ExchangeRate;
import com.kncwallet.wallet.service.BlockchainService;
import com.kncwallet.wallet.util.GenericUtils;
import com.kncwallet.wallet.util.WalletUtils;

import com.kncwallet.wallet.R;

/**
 * @author Andreas Schildbach
 */
public final class ExchangeRatesFragment extends SherlockListFragment implements OnSharedPreferenceChangeListener {
    private AbstractWalletActivity activity;
    private WalletApplication application;
    private Wallet wallet;
    private SharedPreferences prefs;
    private LoaderManager loaderManager;

    private ExchangeRatesAdapter adapter;

    private BigInteger balance = null;
    private boolean replaying = false;
    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.wallet = application.getWallet();
        this.prefs = PreferenceManager.getDefaultSharedPreferences(activity);
        this.loaderManager = getLoaderManager();
    }

    @Override
    public void onActivityCreated(final Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        //setEmptyText(getString(R.string.exchange_rates_fragment_empty_text));

        adapter = new ExchangeRatesAdapter(activity);
        setListAdapter(adapter);
    }

    @Override
    public void onResume() {
        super.onResume();

        activity.registerReceiver(broadcastReceiver, new IntentFilter(BlockchainService.ACTION_BLOCKCHAIN_STATE));

        loaderManager.initLoader(ID_BALANCE_LOADER, null, balanceLoaderCallbacks);
        loaderManager.initLoader(ID_RATE_LOADER, null, rateLoaderCallbacks);

        defaultCurrency = prefs.getString(Constants.PREFS_KEY_EXCHANGE_CURRENCY, null);
        prefs.registerOnSharedPreferenceChangeListener(this);

        updateView();
    }

    @Override
    public void onPause() {
        prefs.unregisterOnSharedPreferenceChangeListener(this);

        loaderManager.destroyLoader(ID_RATE_LOADER);
        loaderManager.destroyLoader(ID_BALANCE_LOADER);

        activity.unregisterReceiver(broadcastReceiver);

        super.onPause();
    }

    @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) {
                prefs.edit().putString(Constants.PREFS_KEY_EXCHANGE_CURRENCY, currencyCode).commit();
            }
        });
    }

    @Override
    public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key) {
        if (Constants.PREFS_KEY_EXCHANGE_CURRENCY.equals(key) || Constants.PREFS_KEY_BTC_PRECISION.equals(key)) {
            defaultCurrency = prefs.getString(Constants.PREFS_KEY_EXCHANGE_CURRENCY, null);

            updateView();
        }
    }

    private void updateView() {
        balance = application.getWallet().getBalance(BalanceType.ESTIMATED);

        if (adapter != null) {
            final String precision = prefs.getString(Constants.PREFS_KEY_BTC_PRECISION,
                    Constants.PREFS_DEFAULT_BTC_PRECISION);
            final int btcShift = precision.length() == 3 ? precision.charAt(2) - '0' : 0;

            final BigInteger base = btcShift == 0 ? GenericUtils.ONE_BTC : GenericUtils.ONE_MBTC;

            adapter.setRateBase(base);
        }
    }

    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) {
            return new CursorLoader(activity, ExchangeRatesProvider.contentUri(activity.getPackageName()), null,
                    null, null, null);
        }

        @Override
        public void onLoadFinished(final Loader<Cursor> loader, final Cursor data) {
            adapter.swapCursor(data);
        }

        @Override
        public void onLoaderReset(final Loader<Cursor> loader) {
            adapter.swapCursor(null);
        }
    };

    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_BTC;

        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 String defaultLocaleCurrency = Currency.getInstance(Locale.getDefault()).getCurrencyCode();
            final boolean isDefaultCurrency = exchangeRate.currencyCode.equals(defaultCurrency)
                    || (defaultCurrency == null && exchangeRate.currencyCode.equals(defaultLocaleCurrency));

            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));
        }
    }
}