ArcGIS Server ADF Ajax frontend and backend interaction (Memo)

Before using arcgis server adf, I thought using ajax was so easy, but I felt quite depressed before using it. OK.

Scenario: I want to obtain the MAP range in the current field of view from the background and return it to the user through xml.

Steps:

1. Write a MapExtentListener class to implement the PhaseListener interface. The Code is as follows:

Package COM. ESRI. ADF. web. templates; import Java. io. ioexception; import Java. util. map; import javax. faces. context. facescontext; import javax. faces. event. phaseevent; import javax. faces. event. phaseid; import javax. faces. event. phaselistener; import Org. w3C. dom. document; import Org. w3C. dom. element; import COM. ESRI. ADF. web. data. webcontext; import COM. ESRI. ADF. web. data. webmap; import COM. ESRI. ADF. web. data. geometry. W Ebextent; import COM. ESRI. ADF. web. faces. renderkit. XML. ajax. ajaxutil; import COM. ESRI. ADF. web. util. webutil; import COM. ESRI. ADF. web. util. xmlutil;/*** get map field of view * @ author likehua **/public class mapextentlistener implements phaselistener {Private Static final long serialversionuid = 1l; @ overridepublic void afterphase) {facescontext context = arg0.getfacescontext (); map Params = context. getex Ternalcontext (). getrequestparametermap (); webcontext = webutil. getwebcontext (context. getviewroot (); webmap map = webcontext. getwebmap (); If (Params. get ("getmapextent ")! = NULL & Params. get ("getmapextent "). equals ("true") {webextent extent = map. getcurrentextent (); double Minx = extent. getminx (); double miny = extent. getminy (); double Maxx = extent. getmaxx (); double Maxy = extent. getmaxy (); document respone = xmlutil. newdocument (); element mapextent = xmlutil. createelement (respone, "mapextent", "", null); xmlutil. createelement (respone, "Maxx", String. valueof (Maxx), mapextent); xmlutil. createelement (respone, "Minx", String. valueof (Minx), mapextent); xmlutil. createelement (respone, "Maxy", String. valueof (Maxy), mapextent); xmlutil. createelement (respone, "miny", String. valueof (miny), mapextent); try {ajaxutil. writeresponse (context, respone);} catch (ioexception e) {// todo auto-generated catch blocke. printstacktrace ();} finally {context. responsecomplete () ;}}@ overridepublic void beforephase (phaseevent arg0) {// todo auto-generated method stub} @ overridepublic phaseid getphaseid () {// todo auto-generated method stubreturn phaseid. apply_request_values ;}}

2. Configure the class in jsf, the configuration file (WebContent/WEB-INF/faces-config.xml) is as follows:

  <lifecycle>    <phase-listener>com.esri.adf.web.templates.MapExtentListener</phase-listener>  </lifecycle>

3. Write a piece of js Code on the front end and send a request to the background. When I mention the js Code, I want to scold the day-killing dojo framework + arcgis js api. The capacity is very large and your IDE will be suspended accidentally. The Code is as follows:

 function requestMapExtent(){       var formId = map.formId;        var url = adf.Utils.getServerUrl(formId);        var params = "getMapExtent=true&" + adf.Utils.buildRequestParams(formId);        adf.Utils.sendAjaxRequest(url, params, true, processMapInfo);      }      function processMapInfo(res){      alert(res.responseText);      }      function  getExtent(){           map=adf.Controls.maps['map1'];           requestMapExtent();      }

HTML entry: <a href = "javascript: void (0)" onclick = "getExtent ()"> current map range </a>. Other code is omitted.

I can't help wondering if ESRI has fallen?