}// end of method frmPreferences_Activated

        private void frmPreferences_Load(object sender, EventArgs e)
        {
            frmPreference = this;

            flpIconSet.Controls.Clear();    // remove any previous icon set used and reload at runtime

            LoadInstalledIconPacks();

            // Weather tab
            #region Test Data (un-comment lines for testing)
            //WeatherLionMain.authorizedProviders = new string[] {
            //        WeatherLionMain.DARK_SKY, WeatherLionMain.OPEN_WEATHER,
            //        WeatherLionMain.WEATHER_BIT, WeatherLionMain.YAHOO_WEATHER };

            //WeatherLionMain.storedPreferences.StoredPreferences.Provider = WeatherLionMain.DARK_SKY;
            //WeatherLionMain.storedPreferences.StoredPreferences.Location = "Pine Hills, FL";
            //WeatherLionMain.storedPreferences.StoredPreferences.Interval = 1800000;
            //WeatherLionMain.storedPreferences.StoredPreferences.UseMetric = false;
            //WeatherLionMain.storedPreferences.StoredPreferences.UseSystemLocation = false;
            //WeatherLionMain.storedPreferences.StoredPreferences.WidgetBackground = "default";
            //WeatherLionMain.storedPreferences.StoredPreferences.IconSet = "hero";
            //List<string> preferenceUpdated = new List<string>();

            #endregion

            // load the combo box with the default weather providers
            cboWeatherProviders.Items.Clear(); // refresh the list
            cboWeatherProviders.Items.AddRange(WeatherLionMain.authorizedProviders);

            // select current weather provider
            cboWeatherProviders.SelectedItem = WeatherLionMain.storedPreferences.StoredPreferences.Provider;

            // select the current weather provider
            cboLocation.Text = WeatherLionMain.storedPreferences.StoredPreferences.Location;

            // select the current refresh period
            string updateInterval = UtilityMethod.MillisecondsToMinutes(
                WeatherLionMain.storedPreferences.StoredPreferences.Interval).ToString();

            lblInterval.Text = $"{updateInterval} min.";
            cboRefreshInterval.SelectedItem = updateInterval;

            chkUseMetric.Checked = WeatherLionMain.storedPreferences.StoredPreferences.UseMetric;

            chkUseSystemLocation.Checked = WeatherLionMain.storedPreferences.StoredPreferences.UseSystemLocation;

            // load the three background options
            picDefault.ImageLocation = DEFAULT_BACKGROUND_IMAGE;
            picAndroid.ImageLocation = ANDROID_BACKGROUND_IMAGE;
            picRabalac.ImageLocation = RABALAC_BACKGROUND_IMAGE;

            // Icon Set tab
            foreach (Control c in tabIconSet.Controls)
            {
                if (c is FlowLayoutPanel)
                {
                    foreach (Control sc in c.Controls)
                    {
                        if (sc is FlowLayoutPanel)
                        {
                            foreach (Control tc in sc.Controls)
                            {
                                if (tc is RadioButton)
                                {
                                    RadioButton rb = tc as RadioButton;

                                    rb.CheckedChanged += new EventHandler(IconSetChanged);
                                }// end of if block
                                else if (tc is PictureBox)
                                {
                                    PictureBox pb = tc as PictureBox;

                                    pb.Click += new EventHandler(SelectIconSetRadioButton);
                                } // end of if block
                            }     // end of for each loop
                        }         // end of if block
                    }             // end of inner foreach block
                }                 // end of if block
            }                     // end of foreach block

            // Background tab
            // Make the radio buttons on each page mutually exclusive
            foreach (Control c in tabBackground.Controls)
            {
                if (c is FlowLayoutPanel)
                {
                    foreach (Control sc in c.Controls)
                    {
                        if (sc is RadioButton)
                        {
                            RadioButton rb = sc as RadioButton;

                            rb.CheckedChanged += new EventHandler(BackgroundChanged);
                        }// end of if block
                        else if (sc is PictureBox)
                        {
                            PictureBox pb = sc as PictureBox;

                            pb.Click += new EventHandler(SelectBackgroundRadioButton);
                        } // end of if block
                    }     // end of inner foreach block
                }         // end of if block
            }             // end of foreach block

            switch (WeatherLionMain.storedPreferences.StoredPreferences.WidgetBackground)
            {
            case "default":
                radDefault.Checked = true;
                break;

            case "android":
                radAndroid.Checked = true;
                break;

            case "rabalac":
                radRabalac.Checked = true;
                break;

            default:
                break;
            }// end of switch block

            // About tab
            rtbAbout.Rtf = @"{\rtf1\pc \qc \b Weather Lion\b0" +
                           @"\line Author: Paul O. Patterson" +
                           @"\line BushBungalo Productions™  2005 - " + DateTime.Now.Year +
                           @"\line Version: 1.0" +
                           @"\line © All rights reserved" +
                           @"\line\line\ql\par Weather Lion is an ongoing effort to create a desktop weather widget " +
                           @"using the C# programming language as well as other languages as I " +
                           @"continue to grow as a computer programmer.\par0" +
                           @"\line\line\line Praise Ye YAH!!!}";

            // ensure that the changes list is empty (comment out during testing)
            WeatherLionMain.runningWidget.preferenceUpdated.Clear();

            LoadKnownPlaces();
        }// end of method frmPreferences_Load