ch.bfh.instacircle.MessageListFragment.java Source code

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Here is the source code for ch.bfh.instacircle.MessageListFragment.java

Source

/*
 *  UniCrypt Cryptographic Library
 *  Copyright (c) 2013 Berner Fachhochschule, Biel, Switzerland.
 *  All rights reserved.
 *
 *  Distributable under GPL license.
 *  See terms of license at gnu.org.
 *  
 */

package ch.bfh.instacircle;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.support.v4.content.LocalBroadcastManager;
import android.view.View;
import android.widget.ListView;
import ch.bfh.instacircle.db.NetworkDbHelper;

/**
 * This class implements the fragment which lists all the messages of the
 * conversation (left tab of the NetworkActiveActivity)
 * 
 * @author Juerg Ritter (rittj1@bfh.ch)
 */
public class MessageListFragment extends ListFragment {

    private static final String STATE_ACTIVATED_POSITION = "activated_position";

    private int mActivatedPosition = ListView.INVALID_POSITION;

    private MessageCursorAdapter mca;

    private Cursor cursor;
    private NetworkDbHelper helper;

    public interface Callbacks {
        public void onItemSelected(String id);
    }

    /*
     * (non-Javadoc)
     * 
     * @see android.support.v4.app.Fragment#onCreate(android.os.Bundle)
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Subscribing to the messageArrived events to update immediately
        LocalBroadcastManager.getInstance(getActivity()).registerReceiver(mMessageReceiver,
                new IntentFilter("messageArrived"));

        // getting access to the database and query it
        helper = NetworkDbHelper.getInstance(getActivity());
        cursor = helper.queryMessages();

        // initializing the adapter and assign it to myself
        mca = new MessageCursorAdapter(getActivity(), cursor);
        setListAdapter(mca);

    }

    /*
     * (non-Javadoc)
     * 
     * @see android.support.v4.app.ListFragment#onViewCreated(android.view.View,
     * android.os.Bundle)
     */
    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        if (savedInstanceState != null && savedInstanceState.containsKey(STATE_ACTIVATED_POSITION)) {
            setActivatedPosition(savedInstanceState.getInt(STATE_ACTIVATED_POSITION));
        }

        this.getListView().setTranscriptMode(2);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * android.support.v4.app.Fragment#onSaveInstanceState(android.os.Bundle)
     */
    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        if (mActivatedPosition != ListView.INVALID_POSITION) {
            outState.putInt(STATE_ACTIVATED_POSITION, mActivatedPosition);
        }
    }

    /**
     * @param activateOnItemClick
     */
    public void setActivateOnItemClick(boolean activateOnItemClick) {
        getListView().setChoiceMode(activateOnItemClick ? ListView.CHOICE_MODE_SINGLE : ListView.CHOICE_MODE_NONE);
    }

    /**
     * @param position
     */
    public void setActivatedPosition(int position) {
        if (position == ListView.INVALID_POSITION) {
            getListView().setItemChecked(mActivatedPosition, false);
        } else {
            getListView().setItemChecked(position, true);
        }

        mActivatedPosition = position;
    }

    /*
     * (non-Javadoc)
     * 
     * @see android.support.v4.app.Fragment#onDestroy()
     */
    @Override
    public void onDestroy() {
        // Unregister since the activity is about to be closed.
        LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(mMessageReceiver);
        super.onDestroy();
    }

    /**
     * we need to update the view as soon as a new message arrives
     */
    private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            mca.changeCursor(helper.queryMessages());
        }
    };
}