Archive for the ‘GIS’ Category

google map css trap 101

November 6, 2007

#1. An div rule will sometimes screw up the overlay popup. Suppose you have #container>#mapDiv, the following will add a weird white bar underneath the popup window (speech bubble when openInfoWindowHTML/openInfoWindow are called):

#container div{

#2. For some mysterious reasons, sometimes the GInfoWindow object gets some extra document div(s) nested when you call openInfoWindowHTML/openInfoWindow and that results in extra white padding space between the real content and teh GInfoWindow object. The workaround is to specify the “maxWidth” property in the GInfoWindowOption object which is the second parameter for an openInfoWindow(HTML) call:

GEvent.addListener(marker, "click", function() {
marker.openInfoWindow(venue.getHTML(), {maxWidth:300});

Google map infoWindow/infoWindowHtml doesn’t render background

February 28, 2007

Because google maps control how the overflowed DIV renders in infoWIndow/infoWIndowHtml class by itself, it sometime overshadows user defined overflow/max-height/max-width properties. It will cause the background tiles of infoWindows/infoWindowHtmls don’t render (lastly found in IE 6 Windows 2k/XP/SP 1, esp the page is iframed by another page, in my case it happens to be in another domain if it matters; or if the infoWindow is opened by click on a DOM object other than the marker it’s associated with). The solutions could be automatically loading the iframed page a second time, or emulating user directly clicking on the marker using javascript.

In the figure, the symptom happens in IE  6(winXP/2k pro) when the page with google maps is framed via a page from another domain. It happens If the user clicks on a ward number on the bottom of the page to pop up an infoWindowHtml the first time the iframe page gets loaded (instead of clicking on the corresponding custom markers within the map.) The fix is to use a trick that first calling “map.openInfoWindow()” then “map.closeInfoWindow()” immediately to simulate a mouse click the first time the map tiles rendered. What will happen in actuality is that no infoWindow will be displayed but it force IE to “rerender” the map tiles to get the right relative positioning for CSS.
unrendered map image tiles

max-height/overflow for google map infowindow

February 28, 2007

//KLUDGE: in windows XP SP2, if the user clicks the num div first to open an infowindow/infowindowhtml, the background images of the marker doesn’t render or renders partially (sometimes the center div bkg renders sometimes the frames images render); while this didn’t happen if the user clicks directly on a marker to open the infowindow/infowindowhtml. This trick helps to circumvent the situation by openinfowindow directly first to emulate the fact that a user clicks on a marker, or loading the framed page a second time.