com.roque.rueda.cashflows.fragments.AccountListFragment.java Source code

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Here is the source code for com.roque.rueda.cashflows.fragments.AccountListFragment.java

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/*
 * Copyright 2014 Roque Rueda.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.roque.rueda.cashflows.fragments;

import java.util.LinkedHashSet;

import com.roque.rueda.android.messenger.ListItemClickNotification;
import com.roque.rueda.cashflows.R;
import com.roque.rueda.cashflows.adapters.AccountAdapter;
import com.roque.rueda.cashflows.database.observer.DataBaseObserver;
import com.roque.rueda.cashflows.database.observer.DatabaseMessenger;
import com.roque.rueda.cashflows.loader.AccountLoader;

import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.support.v4.content.Loader;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

/**
 * Fragment used to display a list of accounts that are
 * related to the user.
 * 
 * @author Roque Rueda
 * @since 06/05/2014
 * @version 1.0
 * 
 */
public class AccountListFragment extends ListFragment implements LoaderCallbacks<Cursor>, DatabaseMessenger {

    // Tag for this class.
    private static final String TAG = "AccountListFragment";
    private static final boolean DEBUG = true;

    // The loader id, this is unique for the ListFragment and LoaderManager.
    private static final int LOADER_ID = 1;

    // Used to store the observers.
    private LinkedHashSet<DataBaseObserver> mObservers;

    /**
     * Loader that loads the information of the accounts.
     */
    private AccountLoader mLoader;

    /**
     * Adapter used to display the information.
     */
    private AccountAdapter mAdapter;

    /**
     * The object who cares when an item of this list is clicked.
     */
    private ListItemClickNotification careTaker;

    /**
     * Called when the activity is created.
     * @param savedInstanceState      Bundle that contains all the 
     * 
     */
    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        // Create an empty adapter.
        mAdapter = new AccountAdapter(getActivity(), null);
        setEmptyText(getActivity().getResources().getString(R.string.loading_accounts));

        // Set the data to the list.
        setListAdapter(mAdapter);
        setListShown(false);

        if (DEBUG) {
            Log.i(TAG, "== Calling initLoader() ==");

            if (getLoaderManager().getLoader(LOADER_ID) == null) {
                Log.i(TAG, "== Initialize new Loader ==");
            } else {
                Log.i(TAG, "== Reuse an existing Loader ==");
            }

        }

        // Store all the database observers.
        mObservers = new LinkedHashSet<DataBaseObserver>();

        // Check if there's an existing loader searching by the Id.
        // If we have a loader it will be reuse.
        mLoader = (AccountLoader) getLoaderManager().initLoader(LOADER_ID, null, this);
        register(mLoader);

        setListerners();
    }

    /**
     * Set the listeners for this ListView.
     */
    private void setListerners() {
        ListView lv = getListView();

        lv.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
        lv.setDivider(getResources().getDrawable(R.color.divider_blue));
        lv.setDividerHeight(1);
    }

    /**
     * Handles the event when this fragment gets attached.
     * @param activity             Parent activity that is used to contain this fragment.
     */
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);

        // Activity that contain this fragment should implement ListItemClickNotification.
        if (!(activity instanceof ListItemClickNotification)) {
            Log.wtf(TAG, "== onAttach(). The parent activity must implement ListItemClickNotification. ==");
            throw new IllegalStateException("The parent activity must implement ListItemClickNotification.");
        }

        careTaker = (ListItemClickNotification) activity;
    }

    /**
     * This method handle the click of each item click. 
     * @param l      {@link ListView} source of the event.
     * @param v      {@link View} the object that was clicked.
     * @param id      Identifier of the item that was press.
     */
    @Override
    public void onListItemClick(ListView l, View v, int position, long id) {
        super.onListItemClick(l, v, position, id);

        // TODO: Get the id.

        careTaker.onItemSelected(id);
    }

    /////////////////////////////////////////////////////////////////////
    // LoaderCallbacks Interface members..
    ///////////////////////////////////////////////////////////////////

    /**
     * Creates an instance of the Loader used in this activity. 
     * @param id         Identifier of the loader.
     * @param args      Arguments used to create the loader.
     */
    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        if (DEBUG) {
            Log.i(TAG, "== onCreateLoader() Creating a new Account Loader. ==");
        }

        AccountLoader loader = new AccountLoader(getActivity());
        return loader;
    }

    /**
     * Called when the load completes this is when we can set the data
     * in our adapter to present the information to the user.
     * 
     * @param loader          Loader that have complete the operation.
     * @param data            Data that has been load.
     */
    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
        if (DEBUG) {
            Log.i(TAG, "== onLoadFinished()  ==");
        }

        mAdapter.changeCursor(data);

        if (isResumed()) {
            setListShown(true);
        } else {
            setListShownNoAnimation(true);
        }
    }

    /**
     * Called when the loader is reset, in this case we should release the data
     * that we have on our adapter.
     * 
     * @param loader         Loader that will be reset.
     */
    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        if (DEBUG) {
            Log.i(TAG, "== onLoaderReset() ==");
        }

        mAdapter.changeCursor(null);
    }

    /////////////////////////////////////////////////////////////////////
    // DataBase Messenger Interface members.
    ///////////////////////////////////////////////////////////////////

    /**
     * Register a new observer to receive the calls when a database change.
     * @param observer Instance observer that will be notify by this Messenger.
     */
    @Override
    public void register(DataBaseObserver observer) {
        mObservers.add(observer);
    }

    /**
     * Unregister a database observer in order to stop receive calls from
     * changes on the database.
     * @param observer Instance observer that will be unregister from this messenger.
     */
    @Override
    public void unregister(DataBaseObserver observer) {
        mObservers.remove(observer);
    }

    /**
     * Notify to the database observer that a table has change.
     * @param tableName Name of the table that was changed.
     */
    @Override
    public void sendNotification(String tableName) {
        for (DataBaseObserver observer : mObservers) {
            observer.notifyTableChange(tableName);
        }
    }

    /**
     * Notify all the register observers that a database change has been made.
     */
    @Override
    public void sendNotification() {
        for (DataBaseObserver observer : mObservers) {
            observer.notifyDatabaseChange();
        }
    }

}