This example demonstrates how to provide AutoComplete suggestions for an address calling Google's Geocoding Service.
Geocoding is the process of converting addresses into geographic coordinates. The Google Geocoding API provides a direct way to access a geocoder via an HTTP request.
Google's Geocoding Service returns a JSON object literal. The service does not provide a JSONP API. AutoComplete cannot use that object directly for security reasons. So the workaround is calling the service using YQL as source.
YUI().use('autocomplete', function (Y) {
var acNode = Y.one('#ac-input');
acNode.plug(Y.Plugin.AutoComplete, {
// Highlight the first result of the list.
activateFirstItem: true,
// The list of the results contains up to 10 results.
maxResults: 10,
// To display the suggestions, the minimum of typed chars is five.
minQueryLength: 5,
// Number of milliseconds to wait after user input before triggering a
// `query` event. This is useful to throttle queries to a remote data
// source.
queryDelay: 500,
// Handling the list of results is mandatory, because the service can be
// unavailable, can return an error, one result, or an array of results.
// However `resultListLocator` needs to always return an array.
resultListLocator: function (response) {
// Makes sure an array is returned even on an error.
if (response.error) {
return [];
}
var query = response.query.results.json,
addresses;
if (query.status !== 'OK') {
return [];
}
// Grab the actual addresses from the YQL query.
addresses = query.results;
// Makes sure an array is always returned.
return addresses.length > 0 ? addresses : [addresses];
},
// When an item is selected, the value of the field indicated in the
// `resultTextLocator` is displayed in the input field.
resultTextLocator: 'formatted_address',
// {query} placeholder is encoded, but to handle the spaces correctly,
// the query is has to be encoded again:
//
// "my address" -> "my%2520address" // OK => {request}
// "my address" -> "my%20address" // OK => {query}
requestTemplate: function (query) {
return encodeURI(query);
},
// {request} placeholder, instead of the {query} one, this will insert
// the `requestTemplate` value instead of the raw `query` value for
// cases where you actually want a double-encoded (or customized) query.
source: 'SELECT * FROM json WHERE ' +
'url="http://maps.googleapis.com/maps/api/geocode/json?' +
'sensor=false&' +
'address={request}"',
// Automatically adjust the width of the dropdown list.
width: 'auto'
});
// Adjust the width of the input container.
acNode.ac.after('resultsChange', function () {
var newWidth = this.get('boundingBox').get('offsetWidth');
acNode.setStyle('width', Math.max(newWidth, 100));
});
// Fill the `lat` and `lng` fields when the user selects an item.
acNode.ac.on('select', function (e) {
var location = e.result.raw.geometry.location;
Y.one('#locationLat').set('text', location.lat);
Y.one('#locationLng').set('text', location.lng);
});
});
Note: be sure to add the yui3-skin-sam classname to the
page's <body> element or to a parent element of the widget in order to apply
the default CSS skin. See Understanding Skinning.
<div id="demo" class="yui3-skin-sam"> <!-- You need this skin class -->
<p>
<label for="ac-input">Enter an address:</label>
<input id="ac-input" type="text" />
</p>
<ul>
<li>Latitude: <strong id="locationLat"></strong></li>
<li>Longitude: <strong id="locationLng"></strong></li>
</ul>
</div>