TimeSlider that Displays Range Within TimeExtent

AlexDeVine

Hello Everyone,

I have created a time-enabled Silverlight WebApp that displays point events over a range of dates from 1520 to 1848. This app includes a time slider and the time period I would like to display on the time slider is 1774 to 1786. I was able to achieve this by modifying the TimeExtent of the map, but, as the app developed I ran into a conflict.

I have maptips pulling data from the attribute fields of the time-aware features which require that the TimeExtent is the full range of dates (from 1520 to 1848). This makes my TimeSlider use the same TimeExtent which reduces its effectiveness.

Anyone know of a way around this? Is there a way to make the TimeSlider function on a subset range within the TimeExtent?

Thank you in advance for any help.

Alex

AlexDeVine

I think I eventually got it 🙂

One option is to set the Map TimeExtent by code instead of by binding. So by code you can expand the TimeExtent until 1520.

Hook up an handler to ValueChanged event of your time slider and define your handler this way:

private void MyTimeSlider_ValueChanged(object sender, TimeSlider.ValueChangedEventArgs e)
{
    var startDate = new DateTime(1520, 1, 1);
    var endDate = e.NewValue.End;
    MyMap.TimeExtent = new TimeExtent(startDate, endDate);
}

Another option is to keep a binding with a converter expanding the time extent as above (for MVVM addict).

Thank you for the suggestion and the code, Dominique! I will give that a shot!

What I did as a workaround, in the interim, was open up the time slider max and min value to the full time extent and established multiple interval sets for the date ranges on the timeslider so that the TimeSpan for the intervals is 10 years for 1520-1774 (long period of low event count), 6 months for 1774-1786 (short period with very high event count) and 2 years for 1786-1848 (moderate length period with tapering event counts). It may be clumsy, but, as a novice programmer I am a bit proud of making that work. 🙂 (Code attached)

//Setting up interval for pre 1774-1786 portion of slider
            DateTime myMinDate_Pre = MyTimeSlider.MinimumValue;
            DateTime myMaxDate_Pre = DateTime.Parse("1773-12-31T00:00:00.0000000Z",
                                  CultureInfo.CurrentCulture,
                                  DateTimeStyles.AdjustToUniversal);
            TimeExtent myTimeExtent_Pre = new TimeExtent(myMinDate_Pre, myMaxDate_Pre);
            TimeSpan myTimeSpan_Pre = new TimeSpan(3650, 0, 0, 0);

            //Setting up interval for 1774-1786 portion of slider
            DateTime myMinDate_Range = DateTime.Parse("1774-01-01T00:00:00.0000000Z",
                                  CultureInfo.CurrentCulture,
                                  DateTimeStyles.AdjustToUniversal);
            DateTime myMaxDate_Range = DateTime.Parse("1786-12-31T00:00:00.0000000Z",
                                  CultureInfo.CurrentCulture,
                                  DateTimeStyles.AdjustToUniversal);
            TimeExtent myTimeExtent_Range = new TimeExtent(myMinDate_Range, myMaxDate_Range);
            TimeSpan myTimeSpan_Range = new TimeSpan(180, 0, 0, 0);

            //Setting up interval for post 1774-1786 portion of slider
            DateTime myMinDate_Post = DateTime.Parse("1787-01-01T00:00:00.0000000Z",
                                 CultureInfo.CurrentCulture,
                                 DateTimeStyles.AdjustToUniversal);
            DateTime myMaxDate_Post = DateTime.Parse("1848-12-31T00:00:00.0000000Z",
                                  CultureInfo.CurrentCulture,
                                  DateTimeStyles.AdjustToUniversal);
            TimeExtent myTimeExtent_Post = new TimeExtent(myMinDate_Post, myMaxDate_Post);
            TimeSpan myTimeSpan_Post = new TimeSpan(730, 0, 0, 0);

            //Creating Date Collection
            //Creating IEnumerables
            IEnumerable<DateTime> myIEnum_Pre = null;
            IEnumerable<DateTime> myIEnum_Range = null;
            IEnumerable<DateTime> myIEnum_Post = null;
            IEnumerable<DateTime> myIEnum_Comb = null;

            //Loading Dates into IEnumerables
            myIEnum_Pre = TimeSlider.CreateTimeStopsByTimeInterval(myTimeExtent_Pre, myTimeSpan_Pre);
            myIEnum_Range = TimeSlider.CreateTimeStopsByTimeInterval(myTimeExtent_Range, myTimeSpan_Range);
            myIEnum_Post = TimeSlider.CreateTimeStopsByTimeInterval(myTimeExtent_Post, myTimeSpan_Post);

            //Creating Lists

            List<DateTime> myIntervalList_Pre = new List<DateTime>();
            List<DateTime> myIntervalList_Range = new List<DateTime>();
            List<DateTime> myIntervalList_Post = new List<DateTime>();

            //Converting IEnumerables to Lists

            myIntervalList_Pre = myIEnum_Pre.ToList();
            myIntervalList_Range = myIEnum_Range.ToList();
            myIntervalList_Post = myIEnum_Post.ToList();

            //Combining Lists

            List<DateTime> myIntervalList_Comb = new List<DateTime>();
            myIntervalList_Comb.AddRange(myIntervalList_Pre);
            myIntervalList_Comb.AddRange(myIntervalList_Range);
            myIntervalList_Comb.AddRange(myIntervalList_Post);

            //Convering Combined List to IEnumerable

            myIEnum_Comb = myIntervalList_Comb;

            //Set intervals to show collection
            MyTimeSlider.Intervals = myIEnum_Comb;