116 lines
5.1 KiB
HTML
116 lines
5.1 KiB
HTML
<!DOCTYPE html>
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
|
|
<meta name="apple-mobile-web-app-capable" content="yes">
|
|
<title>OpenLayers Paging Strategy Example</title>
|
|
<link rel="stylesheet" href="../theme/default/style.css" type="text/css">
|
|
<link rel="stylesheet" href="style.css" type="text/css">
|
|
<script src="../lib/OpenLayers.js"></script>
|
|
<script type="text/javascript">
|
|
var map, photos, paging;
|
|
|
|
/**
|
|
* A specific format for parsing Flickr API JSON responses.
|
|
*/
|
|
OpenLayers.Format.Flickr = OpenLayers.Class(OpenLayers.Format, {
|
|
read: function(obj) {
|
|
if(obj.stat === 'fail') {
|
|
throw new Error(
|
|
['Flickr failure response (',
|
|
obj.code,
|
|
'): ',
|
|
obj.message].join(''));
|
|
}
|
|
if(!obj || !obj.photos ||
|
|
!OpenLayers.Util.isArray(obj.photos.photo)) {
|
|
throw new Error(
|
|
'Unexpected Flickr response');
|
|
}
|
|
var photos = obj.photos.photo, photo,
|
|
x, y, point,
|
|
feature, features = [];
|
|
for(var i=0,l=photos.length; i<l; i++) {
|
|
photo = photos[i];
|
|
x = photo.longitude;
|
|
y = photo.latitude;
|
|
point = new OpenLayers.Geometry.Point(x, y);
|
|
feature = new OpenLayers.Feature.Vector(point, {
|
|
title: photo.title,
|
|
img_url: photo.url_s
|
|
});
|
|
features.push(feature);
|
|
}
|
|
return features;
|
|
}
|
|
});
|
|
|
|
function init() {
|
|
map = new OpenLayers.Map('map');
|
|
var base = new OpenLayers.Layer.OSM();
|
|
|
|
var style = new OpenLayers.Style({
|
|
externalGraphic: "${img_url}",
|
|
pointRadius: 30
|
|
});
|
|
|
|
paging = new OpenLayers.Strategy.Paging();
|
|
|
|
photos = new OpenLayers.Layer.Vector("Photos", {
|
|
projection: "EPSG:4326",
|
|
strategies: [new OpenLayers.Strategy.Fixed(), paging],
|
|
protocol: new OpenLayers.Protocol.Script({
|
|
url: "http://api.flickr.com/services/rest",
|
|
params: {
|
|
api_key: 'b5e8c0e287e678671c3d8b2c0f3ced85',
|
|
format: 'json',
|
|
method: 'flickr.photos.search',
|
|
extras: 'geo,url_s',
|
|
per_page: 100,
|
|
page: 1,
|
|
bbox: [-180, -90, 180, 90]
|
|
},
|
|
callbackKey: 'jsoncallback',
|
|
format: new OpenLayers.Format.Flickr()
|
|
}),
|
|
styleMap: new OpenLayers.StyleMap(style)
|
|
});
|
|
|
|
map.addLayers([base, photos]);
|
|
photos.events.on({"featuresadded": updateButtons});
|
|
map.setCenter(new OpenLayers.LonLat(0, 0), 1);
|
|
}
|
|
|
|
function updateButtons() {
|
|
document.getElementById("prev").disabled = (paging.pageNum() < 1);
|
|
document.getElementById("next").disabled = (paging.pageNum() >= paging.pageCount() - 1);
|
|
document.getElementById("num").innerHTML = paging.pageNum() + 1;
|
|
document.getElementById("count").innerHTML = paging.pageCount();
|
|
}
|
|
</script>
|
|
</head>
|
|
<body onload="init()">
|
|
<h1 id="title">Paging Strategy Example</h1>
|
|
<div id="tags">
|
|
vector, feature, stylemap, paging, strategy, flickr, script
|
|
</div>
|
|
<p id="shortdesc">
|
|
Uses a paging strategy to cache large batches of features and render a page at a time.
|
|
</p>
|
|
<div id="map" class="smallmap"></div>
|
|
Displaying page <span id="num">0</span> of <span id="count">...</span>
|
|
<button id="prev" disabled="disabled" onclick="paging.pagePrevious();">previous</button>
|
|
<button id="next" disabled="disabled" onclick="paging.pageNext();">next</button>
|
|
<br><br>
|
|
<div id="docs">
|
|
<p>The Paging strategy lets you apply client side paging for protocols
|
|
that do not support paging on the server. In this case, the protocol requests a
|
|
batch of 100 features, the strategy caches those and supplies a single
|
|
page at a time to the layer.</p>
|
|
<p>This particular example uses the <a
|
|
href="http://www.flickr.com/services/api/">Flickr API.</a></p>
|
|
</div>
|
|
</body>
|
|
</html>
|