<input type="button" id="btnView" value="Location" onclick="showPosition();" />
<script type="text/javascript">
{literal}
function showPosition() {
if(navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function( position) {
var possinf = "https://www.google.com/maps/?q=" + position.coords.latitude + "," + position.coords.longitude;
document.getElementById("message_text").value = possinf;
});
} else {
alert("Sorry, your browser does not support HTML5 geolocation.");
}
}
{/literal}
</script>