topic Re: Zoom to Selected Polygon in ArcGIS JavaScript Maps SDK Questions

Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 20:27:03 GMT

My code will select and highlight the parcel that is clicked on, but it zooms in to the same spot on the map no matter which parcel I click on. It returns the correct parcel #, and there is only 1 record selected, but it keeps zooming to exact same spot. Any ideas?

for (var i = 0, il = results.features.length; i < il; i++) {

                var graphic = results.features;
                graphic.setSymbol(symbol);
                map.graphics.add(graphic);
                map.centerAndZoom(results.features.geometry, 0.1);
                
                alert(results.features.length); //this returns 1
 }

Re: Zoom to Selected Polygon

JasonZou — Sat, 11 Dec 2021 12:24:34 GMT

Change:

for (var i = 0, il = results.features.length; i < il; i++) {

                var graphic = results.features;
                graphic.setSymbol(symbol);
                map.graphics.add(graphic);
                map.centerAndZoom(results.features.geometry, 0.1);
                
                alert(results.features.length); //this returns 1
 }

To:

var graphic;
for (var i = 0, il = results.features.length; i < il; i++) {
      graphic = results.features;
      graphic.setSymbol(symbol);
      map.graphics.add(graphic);
 }
map.setExtent(esri.graphicsExtent(results.features));

Re: Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 20:54:36 GMT

I made the changes you suggested zj_zou, but the code bombs on this line:

map.setExtent(esri.graphicsExtent(results.features));

Re: Zoom to Selected Polygon

JasonZou — Thu, 19 Sep 2013 20:56:25 GMT

Which version are you using for Javascript API?

Re: Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 20:57:58 GMT

http://js.arcgis.com/3.6/

Re: Zoom to Selected Polygon

JasonZou — Sat, 11 Dec 2021 12:24:37 GMT

Assume you are using AMD style.

Make sure to include "esri/graphicsUtils" to the dependency list, and take graphicsUtils as the alias.

var resultExtent = graphicsUtils.graphicsExtent(results.features);
map.setExtent(resultExtent);

Re: Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 21:17:29 GMT

Code still gets hung up, on this line:

var resultExtent = graphicsUtils.graphicsExtent(results.features);

Re: Zoom to Selected Polygon

JasonZou — Sat, 11 Dec 2021 12:24:39 GMT

Questions:

What error message did you get?

What is the spatial type of the parcel data, point or polygon?

If points, does the map use any tiled/cached basemap?

The code I provided should work for polygons. It won't work for points. For points, here is the code.

For the map with only dynamic map services/layers loaded,

map.centerAndZoom(graphic, 0.5);

For the map with tiled basemap loaded,

map.centerAndZoom(graphic, 12);   // change 12 to any zoom level you like

Re: Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 22:12:43 GMT

1. What error message did you get? No error, the map just 'spins' and I narrowed it down to that line of code.
2. What is the spatial type of the parcel data, point or polygon? polygon
3. If points, does the map use any tiled/cached basemap? Polygonss

The code I provided should work for polygons. It won't work for points. For points, here is the code.

No map showed up when i used this code:

map.centerAndZoom(graphic, 0.5);

No map showed up with this code:

map.centerAndZoom(graphic, 12);

Map showed up, but it was just zoomed in to the middle of my data's extent with this code:

map.centerAndZoom(graphic.geometry, 0.1);

Re: Zoom to Selected Polygon

PatrickThorsell — Thu, 19 Sep 2013 22:53:19 GMT

I figured it out, it was a projection issue 😞
Thanks for your help!

Re: Zoom to Selected Polygon

JasonZou — Fri, 20 Sep 2013 12:16:21 GMT

I guessed it might be the projection issue, but thought setExtent will take care of the reprojection if the spatial reference is different. Anyway, glad to know you get it resolved. Please mark your thread as "Answered" so other people may find it helpful because I believe the issue you experienced is very typical. Thanks.