2 Replies Latest reply on Nov 3, 2016 8:46 PM by Sam Winward

    Motion Chart with (Hopefully!) Disappearing Annotations

    Sam Winward



      I’ve created a motion chart by filtering the display based on a sliding date range.


      As I slide the date range forward (or press play) more of the measure value is revealed. All past dates to the left of the slider remain pictured as I’ve chose ‘Show History: All’.


      My goal is to annotate numerous marks on the measure line – With annotations appearing once their mark is in view, then disappearing when the view has moved say 50 days in the future.


      It is the disappearing that I’m having trouble with. To create such an effect, it seems I need the point on the line (mark), on which the annotation is being displayed, to become null (or hidden) after having been displayed. I tried a variety of calculated fields, but I couldn’t get anything to change past observations based on a current condition (which is what I thought needed to happen).


      I am able to get the annotation to disappear when I select ‘Show History: Last #’, rather than ‘All’. However, this also means the measure line (all measure lines) is vanished from view, and I’d like it to remain pictured once revealed.


      If I was able to do such with a calculated field, under the condition ‘Show History: All’, then I could simply have an underlying line as is without labels, and overlay calculated field line with a label each that disappear sequentially.


      Please let me know if you have any ideas or advice towards this issue. Specific solutions or general approaches are both appreciated! Thanks in advance.






      Here is the annotation appearing once it’s mark is in view, then remaining forever (via ‘Show History: All’):




      Here is the annotation appearing, then disappearing, as I’d like (‘Show History: Last #’); however, I’d like the measure line to remain in view as in the above examples:




        • 1. Re: Motion Chart with (Hopefully!) Disappearing Annotations
          Sujay Paranjpe

          HI Sam,


          Here is what documentation says about the annotations.


          • Mark - select this option to add an annotation that is associated with the selected mark. This option is only available if a mark is selected.
          • Point - select this option to annotate a specific point in the view.
          • Area - select this option to annotate an area in the view such as a cluster of outliers or a targeted region of the view.


          Annotations are generally fairly static.  There’s not much end-user interaction that can change the way they look or function.  They will disappear if the mark or location is no longer visible due to a filter or if a chart’s axis no longer contains the annotated area.


          I think your annotated Mark or Point is going off the view due to multiple conditions.

          • 2. Re: Motion Chart with (Hopefully!) Disappearing Annotations
            Sam Winward

            Hi Sujay,


            Thanks for your response. Maybe I can clarify my question...


            I understand they are static and only appearing and disappearing because the mark they are tied to is present or not based on the sliding filter. I'm trying to give the allusion they are dynamic as the line chart is revealed over time. This works for when they are first revealed, but then I can't get them to drop.


            I'm trying to figure out a way (using calculated fields but maybe there are better methods) to make a mark retroactively become null, so the label tied to it also vanishes.


            The one dynamic variable I have to base the calculated field off is the selected mark as it moves across the x-axis. While I'm able to use this in a calculated field, I'm only able to apply the calculation to the row of the selected mark itself. But for this to work, I think past rows need to change based on a current condition.


            Let me know if this make sense. I'm happy to explain further.