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How to record map navigation?

#1

in our project,we need to realize map’s GoPreviousExtent and GoNextExtent.And at first,i need to record the extent navigated.

as i know,in arcgis,there is a map event,NavigationCompleted,which is triggered after navigation is completed. But,in thinkgeo,i don’t find similar event.The event,ExtentChanged, is triggered several time during the navigation,so it is not what i want.

What should i do?

Thanks.

#2

Hi Channing,



Yes, the ExtentChanged event is not fit for this case as the normal pan will trigger this event, please try the OverlaysDrawn event and then give a condition that ExtentChangedType is not Pan. Like:


    wpfMap1.OverlaysDrawn += wpfMap1_OverlaysDrawn;
 
    wpfMap1.CurrentExtent = new RectangleShape(-13939426.6371, 6701997.4056, -7812401.86, 2626987.386962);
    wpfMap1.Refresh();
}
 
void wpfMap1_OverlaysDrawn(object sender, OverlaysDrawnWpfMapEventArgs e)
{
    if (wpfMap1.ExtentOverlay.ExtentChangedType != ExtentChangedType.Pan)
    {
        RectangleShape currentExtent = e.WorldExtent;
    }
}

Please let us know if any questions.

Thanks,

Troy

#3

Hi Troy,



It works!

Thanks for your help!

#4

That’s great to hear it helps. 
 Any other questions, please feel free to let us know. 
  
 Thanks, 
 Troy

#5

Hi Troy

I have tried to use your code snippet in my project, and it seems that when I pan the map I get ExtentChangedType.None instead of ExtentChangedType.Pan. Maybe a bug has sneaked in? I have also tried in a totally clean project with the same result.

I’m using version 9.0.309.0

Jonas

#6

Hi Jonas,

We can not get the ExtentChangedType.Pan in version 9.0, Please try filtering the extent by binding ExtetnOverlay_Drawing Event, the code maybe like below:

private void ExtentOverlay_Drawing(object sender, DrawingOverlayEventArgs e)
    {
        ExtentInteractiveOverlay overlay = sender as ExtentInteractiveOverlay;
        if(overlay.ExtentChangedType != ExtentChangedType.Pan)
        {
            
        }
        else
        {
            
        }
    }

Thanks,
Peter

#7

Hi Peter

We found another way so I have not tried your suggestion yet, but thanks for your answer! I’m sure it will come in handy later on.

Jonas

#8

Hi Jonas,

Great! Very glad to hear it works for you.

Thanks,
Peter