Auto center the marker on google maps - javascript

I have a marker on google maps on my website. I want the marker to be always at the center of the map whether we zoom in or zoom out.
In the sense, lets say the marker is at boston and the zoom level of map is in such way that we can see the whole Massachusetts state, no matter at which part of the state we zoom into, Boston should be at the center of the map with a newer zoomed level, same thing should happen even when we zoom out.

From the google docs
google.maps.event.addListener(map, 'center_changed', function() {
// 3 seconds after the center of the map has changed, pan back to the
// marker.
window.setTimeout(function() {
map.panTo(marker.getPosition());
}, 3000);
});
You can also use something like this to center the map on an event map.setCenter(marker.getPosition());

Related

Custom overlay in google maps area clicked then zoom in

So I tried to draw grid line on my map and I found a good example on google api documentation here : https://developers.google.com/maps/documentation/javascript/examples/maptype-base
it works , now I have another problem in every area or rectangle which built by grid line, I want them to have a listener on click event and then zoom to area that has been clicked. I have tried like this
google.maps.event.addListener(map, "click", function (e) {
var latLng = e.latLng;
map.setCenter(new google.maps.LatLng(latLng.lat(), latLng.lng()));
map.setZoom(17);
});
it works either, but as you can see the latitude and longitude are the exact location where the cursor / pointer clicked, it's not in the middle of the rectangle or area it means the map after zoomed in is wrong. Could anyone help me with this?
I think the problem is because you are using the overlay(as your grid line), when using the tile overlay Google Maps API breaks up the imagery at each zoom level into a set of square map tiles arranged in a grid. When a map moves to a new location, or to a new zoom level, the Maps API determines which tiles are needed and translates that information into a set of tiles to retrieve.
For example each zoom level increases the magnification by a factor of two. So, at zoom level 1 the map will be rendered as a 2x2 grid of tiles. At zoom level 2, it's a 4x4 grid. At zoom level 3, it's an 8x8 grid, and so on.
So when you zoom in, the coordinates that you click is not always in the middle because tile overlay is not set because of your coordinate.
Check this page for more information about overlay.
You can also check this SO question for more information.

Google map infowindow position on custom marker

I'm not using the Markers in Google Maps because I wish to render custom text and images on my marker, so what I did is a custom marker using Overlays.
The Overlay position is not exactly like the marker so I played a bit with it and now it is rendering exactly like a marker.
The problem now is the infowindow because it doesn't open on top of the overlay but exactly on the position of the overlay, I wish it to be on top of it, around 32px less on the top position.
Looking at the documentation it looks like the infowindow position is related to the object and on the LatLng, so how can I move it?
Here is the code I'm using:
var marker;
marker = new CustomMarker(markerPosition, map, {}); // custom marker is a class I wrote to prototype the overlay.
google.maps.event.addListener(marker, 'click', function() {
myInfowindow.open(map, marker);
});
Quite simple but unfortunately the infowindow is over the marker and not on top of it like if I use a marker.
Set the pixelOffset of the InfoWindow appropriately:
From the documentation on InfoWindows
pixelOffset | Type:Size | The offset, in pixels, of the tip of the info window from the point on the map at whose geographical coordinates the info window is anchored. If an InfoWindow is opened with an anchor, the pixelOffset will be calculated from the anchor's anchorPoint property.

bouncing marker, not bouncing after zoom

this issue I had with google maps, I made a fiddle here.
marker = new google.maps.Marker({
position: latlng,
map: map,
animation: google.maps.Animation.BOUNCE,
title:"Hello World!"
}),
if I drag the map where I can no longer see the marker, and zoom-in (usually 3 or 4 levels), after I zoom-out where I'm able to see my marker, It's not bouncing anymore, if I click on it, it will bounce again.
is this a browser issue, what am I facing here?
I think this is the default behavior of Google Marker animation. Since you left the map extent there's no need to continue the animation behind the scenes.
If you really want to have your marker bouncing whenever you see it you can add the 'bounds_changed' map event. Every time you zoom or drag the map it should check if your marker is within the visible map area and if so, refresh the bounce behavior:
google.maps.event.addListener(map, 'bounds_changed', function(event) {
if(map.getBounds().contains(marker.position)){
marker.setAnimation(google.maps.Animation.BOUNCE);
};
});

Place the Google Maps pegman underneath markers

I have a Google V3 map which uses steetView and some map markers.
The little yellow streetView pegman sits on the map on top of the markers.
Is there a way to change the z-indexes so that my markers will be above the pegman
(so that they can be easlly clicked on without having to zoom in)?
In case anything is not clear, here is a fiddle....
http://jsfiddle.net/spiderplant0/BRkCA/
After a bit of experimenting I came up with this...
$("#map_canvas img[src*=cb_scout]").parent("div").css({'zIndex': -200});
$($("#map_canvas img[src*=cb_scout]")[1]).parent("div").parent("div").css({'zIndex': -200});
This forces the pegman to sit beneath the markers but now the pegman is no longer dragable and each time the map is moved etc, the pegman jumps above the markers again.
To keep the pegman under your markers you can watch for the pov_changed event and reset the z-index after a short delay
$google.maps.event.addListener(panorama, 'pov_changed', function() {
var func=function(){
$("#map_canvas img[src*=cb_scout]").parent("div").css({'zIndex': -200});
}
setTimeout(func,1000);
}
});
You will also need to change the depth of the pegman after the maps moves, which can be accomplished with the following snippet
google.maps.event.addListener(map, 'idle', function() {
google.maps.event.trigger(panorama, 'pov_changed');
})
If you want to be able to drag the pegman, you must first place it above the markers by having a toggle button swap the pegman's depth and add an exception to the pov_changed event handler preventing the pagman from dropping depths when the toggle button is active.
Okay, this may be a bit hacky... (and I hope I understood what you were doing)
1) Disable street view control
2) Make another control with a lower zIndex than the marker you have.
3) Update street view control with the position of the fake street view marker.
http://jsfiddle.net/z7Lp8/
You can set the zIndex of the marker above google.maps.Marker.MAX_ZINDEX in order for the pegman to remain under the marker. MAX_ZINDEX is the maximum default z-index that the API will assign to a marker. Marker z-indexes only work when optimizations are turned off on all markers on the map.
Forked fiddle from question to illustrate: http://jsfiddle.net/brendaz/t4v8nhoq/
var marker1 = new google.maps.Marker({
position: new google.maps.LatLng(54.975, -2.020),
map: map,
zIndex: google.maps.Marker.MAX_ZINDEX + 1,
optimized: false
});

Google Maps: How does Trulia create their custom InfoWIndows?

I really like how Trulia.com has created their custom Google Map InfoWindows.
What I like in particular about Trulia's implementation of the InfoWindow is:
Extends beyond the map border: Google Maps InfoWindows are contained within the map border whereas Trulia's seems to be able to float on-top of the map
Always displays InfoWindow near map Center: Google Maps InfoWindows always display the InfoWindow above the marker whereas Trulia InfoWindows always display the InfoWindow as close the center of the map as possible. For example, if the map marker icon is on the top of the map near the border, the Trulia InfoWindow is displayed below the map marker icon
InfoWindow is displayed on mouse hover (not 'click'): With the default Google Maps InfoWindow, you have to 'click' the map marker icon to display the InfoWindow whereas Trulia InfoWindows are display simply by hovering over the map marker icon.
I found the PdMarker, which is a 3rd party extension for Google Map InfoWindows that accomplishes most of the above bullets but not all. 1) It does not extend beyond the map border, 2) it does not work with Google Maps API version 3 (only version 2).
Anyone know how Trulia is accomplishing their InfoWindow-like implementation on Google Maps API v3?
That's an interesting question. I've been playing with maps recently too. I'm far from expert but I can tell you what I know.
I think the site you mentioned uses a custom div overlay rather than google's info window.
1. InfoWindow is displayed on mouse hover (not 'click')
This can be done with event listeners. For example in maps API v3:
google.maps.event.addListener(marker, 'mouseover', function() {
// myDiv.style.visibility = 'visible'
});
google.maps.event.addListener(marker, 'mouseout', function() {
// myDiv.style.visibility = 'hidden'
});
Here's is a pretty good example of how this can be done.
2. Extends beyond the map border
3. Always displays InfoWindow near map Center
Both of these can be achieved using CSS: (2) using z-index and (3) with position.
There is a similar example of using custom marker tooltips which you can find here. It also shows how you can utilize mouseovers to pop-up tooltips by hovering other elements on your page.
myElement.onmouseover = function(){
google.maps.event.trigger(marker, 'mouseover');
}
myElement.onmouseout = function(){
google.maps.event.trigger(marker, 'mouseout');
}
Finally, another site that makes a good use of maps, although this one uses V2 of the API. Hope this helps.
http://google-maps-utility-library-v3.googlecode.com/svn/trunk/infobox/docs/examples.html
is an extension to google maps which allows you to create custom infowindows

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