We Keep Coding

Preserving Google map zoom to kml layer on checkbox click

I'm attempting to add multiple kml layers to a map that can be turned on and off with check boxes. I got that part working (yay!). When I click on a layer to turn it on, it zooms in (this is fine), but when I unclick to turn the layer off, it zooms back out to my map extent. How do I get it to preserve the zoom of the last loaded layer? Code below.
<script>
var map;
var watershedLayer = new google.maps.KmlLayer ({
url: 'http://mvihes.bc.ca/mapping/watersheds.kmz'
});
var ere1949Layer = new google.maps.KmlLayer ({
url: 'http://mvihes.bc.ca/mapping/ere1949.kmz'
});
function initialize() {
var parksville= new google.maps.LatLng(49.316786, -124.308768);
var mapOptions = {
zoom: 9,
center: parksville
};
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
check();
}
function check()
{
if(document.getElementById('watersheds').checked)
{watershedLayer.setMap(map);}
else
{watershedLayer.setMap(null);}
if(document.getElementById('ere1949').checked)
{ere1949Layer.setMap(map);}
else
{ere1949Layer.setMap(null);}
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
I tried using the preserveViewport function but it just stopped the layer from zooming in, which is not what I wanted. I'm new to javaScript so possibly I'm missing something obvious...any help would be appreciated!
jsfiddle

Set the map-property of a selected layer only when it's not set yet:
function check()
{
if(document.getElementById('watersheds').checked)
{if(!watershedLayer.getMap())watershedLayer.setMap(map);}
else
{watershedLayer.setMap(null);}
if(document.getElementById('ere1949').checked)
{if(!ere1949Layer.getMap())ere1949Layer.setMap(map);}
else
{ere1949Layer.setMap(null);}
}
http://jsfiddle.net/jhagmq7L/16/

You can also attach max and min zoom levels to the map, something to consider the over all map zoom when loading kml layers.
// sets the min and max zoom levels of the map
var opt = { minZoom: 6, maxZoom: 18 };
map.setOptions(opt);

jQuery/Javascript: Google Maps: How to toggle multiple pins on a map?

I have a database of locations which I want to be able to print on a map. Ideally there should be one map with multiple pins for each location you have toggled on. So click a button for location X and it shows up on the map. Click the button for location Y and it shows up on the same map. Click X again and it hides from the map.
Currently I have it so I click on X and the map gets redrawn centered around point X.
Here is the HTML for each button:
<input type='button' data-lat='38.89864400' data-long='-77.05283400'
data-when='20 Aug at 2:00am' value='Location X' class='click' />
The jQuery I'm using is:
jQuery(document).ready(
function initialize() {
jQuery("input.click").click(function() {
showOnMap(jQuery(this).data('lat'), jQuery(this).data('long'), jQuery(this).data('when'));
});
}
);
function showOnMap(lat, long, message) {
var myLatlng = new google.maps.LatLng(lat, long);
var mapOptions = {
zoom: 13,
center: myLatlng
}
var map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
title: message
});
google.maps.event.addDomListener(window, 'load', showOnMap);
}
Is there an easy way to switch from what I have to what I want? I've searched for a while but no one seems to be asking this use case in a browser, just Android (which I'm not doing).
Thanks!

There is an example in the documentation on how to hide/show markers. In short, a marker is:
hidden by setting its map to null
showed by setting its map to map
To do so, you will need to access each marker individually. If you have a definite number of locations, it can be done by naming them with different names (eg var markerLocationX, var markerLocationY, etc). Otherwise, the markers need to be stored in an array.
Supposing you have a definite number of known locations to toggle the markers, your javascript code may look like this:
function toggleMarker(markerName) {
if (markerName.getMap() == null) {
markerName.setMap(map);
} else {
markerName.setMap(null);
}
}

How to add multiple markers for single location on Google Map

I'm using Google Maps version 3 and would like to add two markers for a single location on the map.
One would be the default marker which appears with Google Maps, but second would show the name of the brand associated with that location.
My code is
function initialize() {
var filterLatlng = new google.maps.LatLng(18.928184,72.832601);
var mapOptions = {
center: filterLatlng,
zoom: 19,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
var marker = new google.maps.Marker({
position: filterLatlng,
title:"Filter Shop"
});
var map = new google.maps.Map(document.getElementById("map"), mapOptions);
marker.setMap(map);
}

You probably want this library:
http://code.google.com/p/google-maps-utility-library-v3/source/browse/trunk/maplabel/src/maplabel.js?r=303
It will allow you to add a label on the map.
That label will be attached to a hidden marker like you described.
The use is quite simple you should be able to figure it out quite easy.

How to get some information in google maps without click event on marker and show this in a div, other than infoWindow

Hi I am showing some markers on my google map and on click of the marker, I am calling the click event and showing some info about that place to the right side(area other than Map and not as an infoWindow). Now this event gets fired on click, and by default when page loads my div remains blank, How can I have the div the basic information being shown up once the map loads up. I need to show the information that corresponds to the marker that is the center point of the map, and later when the users click the marker icons the info should change and correspond to the particular marker being clicked
I have tried something but it doesn't work:
function loadMap() {
var myLatlng = new google.maps.LatLng(40.46998, -3.68705);
var myOptions = {
zoom: 3,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map"), myOptions);
var places = [];
places.push(new google.maps.LatLng(51.43581, -0.51744));
places.push(new google.maps.LatLng(48.87187, 2.31764));
places.push(new google.maps.LatLng(45.45979, 9.19681));
var infowindow;
for(var i = 0; i<places.length; i++) {
var marker= new google.maps.Marker({
position: places[i],
map: map,
title: 'Place' + i
});
(function (i,marker){
google.maps.event.addListener(marker, 'click' , function() {
infowindow.setContent('PLace Number' + i)
infowindow.open(i, marker)
});
});(i, marker);
}
}
$("document").ready(function () {
loadMap();
});
UPDATE EDITED
Basically I need something like Layer KML features
But the info should come on the right hand side by default for the first time. Later on when the marker is clicked, the info should change. I am also not adamant that I need this info in a kml file(xml is fine with me as well). I can just have a marker and info should popup on click and for the first time be default as well depending on the location of the user.
Bottom Line: I need the info to appear on click of a marker and by default when the page loads the info should appear corresponding to the center point of the map. which means users coming from different locations will see different info's corresponding to their location from where they are coming.(I am centering the map based on users location)

You can use the addDomListener event of the google maps api. Something like this:
<script>
function initialize() {
// Map initialization
}
google.maps.event.addDomListener(window, 'load', initialize);
</script>
<body>
<div id="map_canvas"></div>
</body>
Although the above code is Maps Javascript API code, the addDomListener() method binds to the window object of the browser and allows the API to communicate with objects outside of the API's normal domain.
further reading
Actually the basic Idea is that you need to read an XMl and parse the data and and show this in a seperate div on right side., This div you can create dynamically when you load the map e-g:
$("#body").append("<div class='newdiv'></div>")

From the google Docs in the section about InfoWindow:
Note that if you call open() without passing a marker, the InfoWindow
will use the position specified upon construction through the
InfoWindow options object.
So in your code, why don't you simply init your infoWindow and call the open() method? I am not particularly familiar with the api, but how about:
var infowindow = new google.maps.InfoWindow({
content: 'your initial text'
});
infowindow.open();
Or if you need the marker for special purposes on the infowindow, init an marker with the center position and use that in the infowindow.open(your_initial_pos) call.

You can use jQuery to .triger() a click event on the first marker on document.ready:
$(marker).trigger('click');
This will run the code you have already written and make it so when the page loads your div will be populated with data from whatever element you trigger the click on.
When you bind to document.ready you don't need encapsulate document in quotes:
$(document).ready(function () {...});
Or you could use the short-hand if you're into that sort of thing:
$(function () {...});
UPDATE
You can place the trigger function call after your for loop where you are setting up the markers:
for(var i = 0; i<places.length; i++) {
var marker= new google.maps.Marker({
position: places[i],
map: map,
title: 'Place' + i
});
(function (i,marker){
google.maps.event.addListener(marker, 'click' , function() {
infowindow.setContent('PLace Number' + i)
infowindow.open(i, marker)
});
});(i, marker);
//only run on the first marker
if (i === 0) {
//trigger a click event to show the first info-window
$(marker).trigger('click');
}
}

You can fire a tilesloaded event on the map object. Check out the Map reference for events
tilesloaded waits until the map tiles are actually loaded before firing. Using your code, you could do something like this:
function loadMap() {
var myLatlng = new google.maps.LatLng(40.46998, -3.68705);
var myOptions = {
zoom: 3,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map"), myOptions);
google.maps.event.addListener(map, 'tilesloaded', function() {
doSomething();
});

Google Maps API v3: Close infowindow when DOM element is clicked

I'm playing around with Google maps for the first time, so I looked at a nice tutorial over at CSS Tricks: http://css-tricks.com/google-maps-slider/ I like working with jQuery better than pure JS, and this tutorial makes a nice way to click on a place in a list to display the marker in the map.
I liked it that way, but I need to add infowindows to the marker. Which I did, but when I click on a place on the list and the map pans away, the infowindow stays open! I think it's because I need to attach the infowindow.close() to the event of clicking on a "#locations li".
Here's my code, which runs on document.ready:
$(function() {
var chicago = new google.maps.LatLng(41.924832, -87.697456),
pointToMoveTo,
first = true,
curMarker = new google.maps.Marker({}),
$el;
var myOptions = {
zoom: 10,
center: chicago,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
var map = new google.maps.Map($("#map_canvas")[0], myOptions);
$("#locations li").click(function() {
$el = $(this);
if (!$el.hasClass("hover")) {
$("#locations li").removeClass("hover");
$el.addClass("hover");
if (!first) {
// Clear current marker
curMarker.setMap();
// Set zoom back to Chicago level
// map.setZoom(10);
}
// Move (pan) map to new location
function move(){
pointToMoveTo = new google.maps.LatLng($el.attr("data-geo-lat"), $el.attr("data-geo-long"));
map.panTo(pointToMoveTo);
}
move();
// Add new marker
curMarker = new google.maps.Marker({
position: pointToMoveTo,
map: map
});
// Infowindow: contenido
var contentString = '<p>'+$el.find("h3").html()+'</p>';
contentString += 'hola' ;
var infowindow = new google.maps.InfoWindow(
{
size: new google.maps.Size(150,50),
content: contentString
});
// On click, zoom map
google.maps.event.addListener(curMarker, 'click', function() {
//map.setZoom(14);
infowindow.open(map,curMarker);
});

It looks like you're creating a new InfoWindow for each marker. Quoting from the Google Maps API Docs:
If you only want one info window to display at a time (as is the behavior on Google Maps), you need only create one info window, which you can reassign to different locations or markers upon map events (such as user clicks).
Therefore, you may simply want to create one InfoWindow object just after you initialize your map, and then handle the click event handler as follows:
google.maps.event.addListener(curMarker, 'click', function() {
infowindow.setContent(contentString);
infowindow.open(map, curMarker);
});
Then the InfoWindow should automatically close when you click on a new marker without having to call the close() method.