Get the current camera target(latitude/longitude) position.
<div class="map" id="map_canvas">
<span class="smallPanel"><button>Click here</button></span>
</div>
var div = document.getElementById("map_canvas");
var map = plugin.google.maps.Map.getMap(div);
var button = div.getElementsByTagName('button')[0];
button.addEventListener('click', function() {
// Show the current camera target position.
var target = map.getCameraTarget();
alert([
"lat: " + target.lat,
"lng: " + target.lng
]);
});