Openlayers中的KML图层在本地主机上不起作用 [英] KML layer in Openlayers doesn't work on localhost
问题描述
我在OpenLayers中渲染KML文件时遇到了一个奇怪的问题。这似乎很容易，但事实并非如此。我已经从这里开始了一个例子 OpenLayers示例。我想添加自己的KML。它没有工作。我已经创建了绝对网址示例的本地副本，如下所示：
< html>
< head>
< meta http-equiv =Content-Typecontent =text / html; charset = utf-8>
< meta name =viewportcontent =width = device-width，initial-scale = 1.0，maximum-scale = 1.0，user-scalable = 0>
< meta name =apple-mobile-web-app-capablecontent =yes>
< link rel =stylesheethref =http://openlayers.org/dev/theme/default/style.csstype =text / css/>
< link rel =stylesheethref =http://openlayers.org/dev/examples/style.csstype =text / css/>
< script src =http://openlayers.org/dev/OpenLayers.js>< / script>
< style type =text / css>
html，body {
height：100％;
}
#map {
width：100％;
身高：80％;
border：1px纯黑色;
}
.olPopup p {margin：0px; font-size：.9em;}
.olPopup h2 {font-size：1.2em; }
< / style>
< script type =text / javascript>
var lon = 5;
var lat = 40;
var zoom = 5;
var map，select;
函数init（）{
map = new OpenLayers.Map（'map'）;
var wms = new OpenLayers.Layer.WMS（
OpenLayers WMS，
http://vmap0.tiles.osgeo.org/wms/vmap0，
{layers：'basic'}
）;
var sundials = new OpenLayers.Layer.Vector（KML，{
projection：map.displayProjection，
strategies：[new OpenLayers.Strategy.Fixed（）]，
协议：新的OpenLayers.Protocol.HTTP（{
url：http://openlayers.org/dev/examples/kml/sundials.kml，
格式：new OpenLayers.Format .KML（{
extractStyles：true，
extractAttributes：true
}）
}）
}）;
map.addLayers（[wms，sundials]）;
警报（已损毁）;
select = new OpenLayers.Control.SelectFeature（sundials）;
sundials.events.on（{
featureselected：onFeatureSelect，
featureunselected：onFeatureUnselect
}）;
map.addControl（select）;
select.activate（）;
map.zoomToExtent（new OpenLayers.Bounds（68.774414,11.381836,123.662109,34.628906））;
}
函数onPopupClose（evt）{
select.unselectAll（）;
}
function onFeatureSelect（event）{
var feature = event.feature;
//由于KML是用户生成的，因此对
// Javascript进行天真的保护。
var content =< h2>+ feature.attributes.name +< / h2> + feature.attributes.description;
if（content.search（< script）！= -1）{
content =包含Javascript的内容！下面的转义内容< br> + content.replace（/< / g，& lt;）;
}
popup = new OpenLayers.Popup.FramedCloud（chicken，
feature.geometry.getBounds（）。getCenterLonLat（），
OpenLayers.Size（100,100），
content，
null，true，onPopupClose）;
feature.popup = popup;
map.addPopup（popup）;
}
function onFeatureUnselect（event）{
var feature = event.feature;
if（feature.popup）{
map.removePopup（feature.popup）;
feature.popup.destroy（）;
删除feature.popup;
}
}
< / script>
< / head>
< body onload =init（）>
< h1 id =title> KML图层示例< / h1>
< div id =tags>
kml，popup，功能
< / div>
< p id =shortdesc>
演示如何在底图上加载和显示KML文件。
< / p>
< div id =mapclass =smallmap>< / div>
< div id =docs>< / div>
< / body>
< / html>
它不渲染。我尝试将KML网址更改为本地副本sundial.kml（ url：http://openlayers.org/dev/examples/kml/sundials.kml， - > url：/
最后，我想添加自己的KML文件，但他们不显示，我应该怎么办？
在此先感谢
Rafal
OpenLayers.Protocol.HTTP ，它不会加载类型为 file：//directory/file.kml 的地址。
但是我不知道为什么你的发布代码没有渲染，我现在正在面临同样的问题，我可以告诉你的是什么都不起作用。
Openlayers文档解释了如何使用GML层来加载一个KML层，不幸的是，他们在文档中给出的代码片段与他们的实际示例，它使用Vector层，就像大多数其他KML（和GML）示例一样。
无论如何我都复制了示例代码，但根据文档将Vector层更改为 var layer = new OpenLayers.Layer.GML（GML，gml / polygon.xml）; 。然后我制作了Openlayers.js，polygon.xml和.css样式表的本地副本，并将url更改为指向我的本地副本。所以一切都是本地的。
<！DOCTYPE html>
< html>
< head>
< meta http-equiv =Content-Typecontent =text / html; charset = utf-8>
< meta name =viewportcontent =width = device-width，initial-scale = 1.0，maximum-scale = 1.0，user-scalable = 0>
< meta name =apple-mobile-web-app-capablecontent =yes>
< title> GML不呈现< / title>
< link rel =stylesheethref =defaultstyle.csstype =text / css>
< link rel =stylesheethref =examplesstyle.csstype =text / css>
< script src =OpenLayers.js>< / script>
< script type =text / javascript>
var map;
函数init（）{
map = new OpenLayers.Map（'map'）;
var wms = new OpenLayers.Layer.WMS（
OpenLayers WMS，http://vmap0.tiles.osgeo.org/wms/vmap0，
{layers：'basic '}
）;
var layer = new OpenLayers.Layer.GML（GML，gml / polygon.xml）;
map.addLayers（[wms，layer]）;
map.zoomToExtent（new OpenLayers.Bounds（
-3.92，44.34，4.87，49.55
））;
}
< / script>
< / head>
< body onload =init（）>
< div id =mapclass =smallmap>< / div>
< / body>
< / html>
无效。
我也尝试了文档中的建议：
var layer = new OpenLayers.Layer.GML（KML，kml / lines.kml，{
格式：OpenLayers.Format.KML，
formatOptions：{$ b $'extractStyles'：true
}
}）;
无效。
甚至还有一个将本地存储的GML矢量数据加载到底图上的特定示例。它使用与文档相同的代码，所以不用说，它不起作用。我无法超链接到它，因为我还没有足够的声望制作三个超链接，但是如果您搜索示例中的GML，就可以找到它。
Openlayers具有安全功能，可以很难从非常不同的位置加载数据和JavaScript（如果真的必须这样做，则需要一个名为proxyhost的解决方法）。但我不明白，当所有的URL指向本地主机时会如何。
请温和，这是我的第一篇文章！
编辑：事实证明，a）这是一个浏览器安全功能，而不是OpenLayers，和b）它不允许本地主机上的脚本加载本地主机上的任何其他文件，甚至如果你离线。 Chrome / Chromium具有命令行参数-allow-file-access-from-files。使用这个参数，上面的例子工作。其他解决方法（谷歌他们）似乎棘手。
I have strange problem with rendering KML file in OpenLayers. It seems to be easy, but it's not. I've started with an example from here OpenLayers example . I wanted to add my own KML. It didn't work. I've created a local copy of the example with absolute urls, as follows:
<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">
<link rel="stylesheet" href="http://openlayers.org/dev/theme/default/style.css" type="text/css" />
<link rel="stylesheet" href="http://openlayers.org/dev/examples/style.css" type="text/css" />
<script src="http://openlayers.org/dev/OpenLayers.js"></script>
<style type="text/css">
html, body {
height: 100%;
}
#map {
width: 100%;
height: 80%;
border: 1px solid black;
}
.olPopup p { margin:0px; font-size: .9em;}
.olPopup h2 { font-size:1.2em; }
</style>
<script type="text/javascript">
var lon = 5;
var lat = 40;
var zoom = 5;
var map, select;
function init(){
map = new OpenLayers.Map('map');
var wms = new OpenLayers.Layer.WMS(
"OpenLayers WMS",
"http://vmap0.tiles.osgeo.org/wms/vmap0",
{layers: 'basic'}
);
var sundials = new OpenLayers.Layer.Vector("KML", {
projection: map.displayProjection,
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "http://openlayers.org/dev/examples/kml/sundials.kml",
format: new OpenLayers.Format.KML({
extractStyles: true,
extractAttributes: true
})
})
});
map.addLayers([wms, sundials]);
alert("deded");
select = new OpenLayers.Control.SelectFeature(sundials);
sundials.events.on({
"featureselected": onFeatureSelect,
"featureunselected": onFeatureUnselect
});
map.addControl(select);
select.activate();
map.zoomToExtent(new OpenLayers.Bounds(68.774414,11.381836,123.662109,34.628906));
}
function onPopupClose(evt) {
select.unselectAll();
}
function onFeatureSelect(event) {
var feature = event.feature;
// Since KML is user-generated, do naive protection against
// Javascript.
var content = "<h2>"+feature.attributes.name + "</h2>" + feature.attributes.description;
if (content.search("<script") != -1) {
content = "Content contained Javascript! Escaped content below.<br>" + content.replace(/</g, "<");
}
popup = new OpenLayers.Popup.FramedCloud("chicken",
feature.geometry.getBounds().getCenterLonLat(),
new OpenLayers.Size(100,100),
content,
null, true, onPopupClose);
feature.popup = popup;
map.addPopup(popup);
}
function onFeatureUnselect(event) {
var feature = event.feature;
if(feature.popup) {
map.removePopup(feature.popup);
feature.popup.destroy();
delete feature.popup;
}
}
</script>
</head>
<body onload="init()">
<h1 id="title">KML Layer Example</h1>
<div id="tags">
kml, popup, feature
</div>
<p id="shortdesc">
Demonstrates loading and displaying a KML file on top of a basemap.
</p>
<div id="map" class="smallmap"></div>
<div id="docs"></div>
</body>
</html>
It doesn;t render. I tried to change KML url to my local copy of sundial.kml (url: "http://openlayers.org/dev/examples/kml/sundials.kml", -> url: "/sundials.kml, and it didn't work either. I don't have Idea why.
Finally I want to add my own KML files, but they do not show either. What should I do?
Thanks in advance Rafal
The reason that your local copy of sundials.kml won't render is that you're using OpenLayers.Protocol.HTTP, which won't load an address of the kind file://directory/file.kml.
But I've no idea why your posted code doesn't render. I'm currently wrestling with the same problem. All I can tell you is what else doesn't work.
The Openlayers documentation explains how a GML layer can be used to load a KML layer. Unfortunately, the code snippet they give in the documentation doesn't match their actual example, which uses a Vector layer just like most of their other KML (and GML) examples.
I copied the example code anyway, but changed the Vector layer to var layer = new OpenLayers.Layer.GML("GML", "gml/polygon.xml");, as per the documentation. Then I made local copies of Openlayers.js, polygon.xml and the .css stylesheets, and changed the urls to point to my local copies. So everything is local.
<!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>GML Doesn't Render</title>
<link rel="stylesheet" href="defaultstyle.css" type="text/css">
<link rel="stylesheet" href="examplesstyle.css" type="text/css">
<script src="OpenLayers.js"></script>
<script type="text/javascript">
var map;
function init(){
map = new OpenLayers.Map('map');
var wms = new OpenLayers.Layer.WMS(
"OpenLayers WMS", "http://vmap0.tiles.osgeo.org/wms/vmap0",
{layers: 'basic'}
);
var layer = new OpenLayers.Layer.GML("GML", "gml/polygon.xml");
map.addLayers([wms, layer]);
map.zoomToExtent(new OpenLayers.Bounds(
-3.92, 44.34, 4.87, 49.55
));
}
</script>
</head>
<body onload="init()">
<div id="map" class="smallmap"></div>
</body>
</html>
It doesn't work.
I also tried the suggestion from the documentation:
var layer = new OpenLayers.Layer.GML("KML", "kml/lines.kml", {
format: OpenLayers.Format.KML,
formatOptions: {
'extractStyles': true
}
});
It doesn't work.
There is even a specific example of loading "locally stored GML vector data on a basemap". It uses the same code as the documentation, so, needless to say, it doesn't work. I can't hyperlink to it because I haven't enough reputation yet to make three hyperlinks, but you can find it if you search the examples for "GML".
Openlayers has a security feature to make it difficult to load data and javascript from wildly different locations (and a workaround called "proxyhost" if you really have to do this). But I can't see how that would get involved when all the urls point to the localhost.
Please be gentle, this is my first post!
EDIT: It turns out that a) it's a browser security feature, not OpenLayers, and b) it doesn't allow a script on the localhost to load any other file on the localhost, even if you're offline. Chrome/Chromium has a command-line parameter -allow-file-access-from-files. Using this parameter, the above examples work. Other workarounds (Google them) seem tricky.
这篇关于Openlayers中的KML图层在本地主机上不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
