Problem refreshing theme based FOI

Question

Hi,
We have a map and we want to display shops on it. That works, however new new call containing a different collection of shop IDs does not result in a refresh of the map in the sense that these new shops appear on it. I have been studying the JavaScript API, and I thought that I did find the (best) way to do this, namely the following flow (omitting less relevant code):
1. First we start with a function that initializes the MapViewer object:
function showRasterMap(){
raster_mvo = new MVMapView(document.getElementById("rastermap"), baseURL);
var base_map = new MVBaseMap("MVDS.RASTER_MAPCACHE");
base_map.setVisible(true);
raster_mvo.addBaseMapLayer(base_map);
raster_mvo.setCenter(MVSdoGeometry.createPoint(center_x, center_y, 90112));
raster_mvo.setZoomLevel(0);
raster_mvo.addScaleBar();
raster_mvo.display();      
2. Then when the end user clicks on a node of a tree widget, a second function is called that collects the shop IDs and passes that array to a function that sets the query parameter.
function RasterWindow_loadRasterKaart(){
var data = dojo.json.serialize({nodeId: list.activeNodeId});
request = {data: data, action: "getBaseIds"};
     dojo.io.bind({
     url: "list.do",
     load: rasterWindow.bolletjesCallback,
     mimetype: "text/plain",
     content: request,
     preventCache: true
function RasterWindow_bolletjesCallback(type, data, evt){
var arr = dojo.json.evalJson(data);
prepareArraydMap(arr);
3. Now the interesting part comes, namely the question how to (best) refresh the map. I solved like this: when the ThemeBasedFOI doesn't exist yet, then it will be initialized and added to the MapView object. But when it already exists, then it needs to bind the new query parameter, execute the query and refresh the MapView object. The reason for proceeding like this, is of course to avoid to re-create the ThemeBasedFOI and MapView objects again and again (which doesn't look like a good coding practise and intuitively looks less performing). So my little function became something like this:
function prepareArraydMap(arr){
var myArrayParam = new ArrayParameter(arr,'narray','t_unitids')
if (raster_foi == null) {
raster_foi = new MVThemeBasedFOI('rasterUnitsFoi','MVDS.THEMERASTERUNITS', baseURL);
raster_foi.setQueryParameters(myArrayParam);      
raster_foi.setBringToTopOnMouseOver(true);
raster_foi.addEventListener("mouse_right_click", foiRightClick);
raster_foi.enableInfoTip(true);
raster_foi.setVisible(true);
raster_mvo.addThemeBasedFOI(raster_foi);
else {
     raster_foi.setQueryParameters(myArrayParam);
     raster_foi.setVisible(true);
     raster_foi.refresh(false);
raster_mvo.display();
The problem is however, it does not work. The first request to display the shops on the map is: request=getfoi&version=1.0&theme=MVDS.THEMERASTERUNITS&bbox=-265933.3333333333:29066.666666666686:546866.6666666666:841866.6666666666&width=1536&height=1536&paramnum=1&param1=257476,118262&paramtype1=narray&sqltype1=t_unitids&area=yes&dstsrid=90112
Subsequent requests (for different shops) have a likewise request, but do not result in shops being displayed (only the map is visible). Also: a strange post appeared (in FireBug), namely: POST http://localhost:8888/mapviewer/ReturnLocaleOper, which contains:
i0=Pan%20NorthWest&i1=Pan%20North&_i2=Pan%20NorthEast&_i3=Pan%20West&_i4=Pan%20East&_i5=Pan%20SouthWest&_i6=Pan%20South&_i7=Pan%20SouthEast&_i8=Slider%20Bar&_i9=Drag%20To%20Zoom&_i10=Zoom%20In&_i11=Zoom%20Out&_i12=Scale%20at%20the%20center%20of%20the%20map&_i13=MapView%20baseURL%20is%20not%20set,%20please%20check&_i14=km&_i15=mi&_i16=m&_i17=ft&_i18=Home
_i17="ft";
_i11="Zoom Out";
_i7="Pan SouthEast";
_i3="Pan West";
_i18="Home";
_i15="mi";
_i14="km";
_i10="Zoom In";
_i6="Pan South";
_i0="Pan NorthWest";
_i9="Drag To Zoom";
_i1="Pan North";
_i13="MapView baseURL is not set, please check";
_i5="Pan SouthWest";
_i12="Scale at the center of the map";
_i8="Slider Bar";
_i2="Pan NorthEast";
_i16="m";
_i4="Pan East";
Date: Fri, 22 Dec 2006 00:41:37 GMT
Server: Oracle Containers for J2EE
Connection: Keep-Alive
Keep-Alive: timeout=15, max=100
Content-Type: text/html;charset=UTF-8
Transfer-Encoding: chunked
I am lost. I would very much appreciate any help.
Greetings, Erik

Answer 1

I have separated the map code from the main application, and it works now: I can display FOIs and display another set of FOIs by calling the refresh method of the MVThemeBasedFOI. The JavaScript code is quite simple:
function showRasterMap() {
raster_mvo = new MVMapView(document.getElementById("rastermap"), baseURL);
raster_mvo.addBaseMapLayer(new MVBaseMap("MVDS.RASTER_MAPCACHE"));
raster_mvo.setCenter(MVSdoGeometry.createPoint(150000, 450000, 90112));
raster_mvo.setZoomLevel(0);
raster_mvo.addScaleBar();
raster_mvo.display();
function showRasterFOI(arr) {
var t0 = new Date();
var arrParam = new ArrayParameter(arr, 'narray', 't_unitids');
if (raster_foi == null) {
raster_foi = new MVThemeBasedFOI('rasterUnitsFoi', 'MVDS.THEMERASTERUNITS', baseURL);
raster_foi.setQueryParameters(arrParam);
//raster_foi.setBringToTopOnMouseOver(true);
raster_foi.enableInfoTip(true);
raster_foi.setVisible(true);
raster_mvo.addThemeBasedFOI(raster_foi);
else {
raster_foi.addEventListener('after_refresh', function() {
var t1 = new Date();
var diff = t1 - t0;
alert('timer: ' + diff + ' msec');
raster_foi.setQueryParameters(arrParam);
raster_foi.refresh(true);
//TODO: check if zooming is required
//raster_mvo.display(); THIS KILLS PERFORMANCE
So everything looks fine here, except the performance, namely in my browser it takes 33 seconds to display a single FOI !
However I had a look on the code again, and I found that the last call to display the MVMapView object resulted into the gigantic perfomance breakdown as mentioned above. When reading the API, I didn't get consious of this performance penalty. The API just says about the display method: "This method displays all map content inside the map container (which is an HTML DIV element defined in the web page)."
Maybe you could find time to extend the API with information and advices of how to best use it, especially witn respect to performance.
I am happy that I managed to solve this issue that turned our hear into grey color.