topic Re: Zooming to just beyond full extent in ArcGIS API for Silverlight Questions

Zooming to just beyond full extent

JackCibor — Tue, 26 Oct 2010 21:41:03 GMT

In my silverlight apps i am trying to have the map zoom to the results of queries or GP tasks (graphics layers) with the following C# code:

MyMap.ZoomTo(graphicsLayer.FullExtent)

When i do so, the furthest outlying feature is right on the edge of the map. So I want to zoom to something just greater than the full extent so there is a little space between my furthest out feature and the edge of the map.

So I came up with something like this:

                Envelope myExtent = new Envelope();
                myExtent.XMax = ((graphicsLayer.FullExtent.XMax) + 0.02);
                myExtent.XMin = ((graphicsLayer.FullExtent.XMin) - 0.02);
                myExtent.YMax = ((graphicsLayer.FullExtent.YMax) + 0.02);
                myExtent.YMin = ((graphicsLayer.FullExtent.YMin) - 0.02);
                //MyMap.ZoomTo(graphicsLayer.FullExtent)
                MyMap.ZoomTo(myExtent);

But this only works for zooming in a narrow range of scales. If scales vary greatly this kind of approach does not work well.

Have you seen any examples of a better way to do this??

Re: Zooming to just beyond full extent

STharshini — Wed, 27 Oct 2010 00:58:02 GMT

In my silverlight apps i am trying to have the map zoom to the results of queries or GP tasks (graphics layers) with the following C# code:

MyMap.ZoomTo(graphicsLayer.FullExtent)

When i do so, the furthest outlying feature is right on the edge of the map. So I want to zoom to something just greater than the full extent so there is a little space between my furthest out feature and the edge of the map.

So I came up with something like this:

                Envelope myExtent = new Envelope();
                myExtent.XMax = ((graphicsLayer.FullExtent.XMax) + 0.02);
                myExtent.XMin = ((graphicsLayer.FullExtent.XMin) - 0.02);
                myExtent.YMax = ((graphicsLayer.FullExtent.YMax) + 0.02);
                myExtent.YMin = ((graphicsLayer.FullExtent.YMin) - 0.02);
                //MyMap.ZoomTo(graphicsLayer.FullExtent)
                MyMap.ZoomTo(myExtent);

But this only works for zooming in a narrow range of scales. If scales vary greatly this kind of approach does not work well.

Have you seen any examples of a better way to do this??

Have you tried :myMap.Zoom();Please check the below link

http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Map~Zoom.html

http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Map~ZoomFactor.html

Re: Zooming to just beyond full extent

JackCibor — Wed, 27 Oct 2010 16:27:17 GMT

Have you tried :myMap.Zoom();Please check the below link

http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Map~Zoom.html

http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Map~ZoomFactor.html

It seems that the zoom factor is for double clicking and scrolling with the mouse. And MyMap.Zoom zooms in a specified amount from the current extent. So I tried

Map1.ZoomTo(graphicsLayer.FullExtent);
Map1.Zoom(0.9);

But when I do this the second line executes an instant after the first line, so the map is zoomed by the second line before it has a chance to zoom to the extent of the graphics layer.