我正在使用Openlayers制作自己的KML图层地图。我希望通过弹出窗口访问我的KML文件中的属性,我已经成功实现了这一点,但问题是如何使多个KML图层可选择,我只能选择最上层的图层。我一直在寻找解决方案,但什么都不起作用,非常感谢您的帮助。我的代码如下:
var map;
function init() {
var options = {
scales: [500, 1000, 2500, 5000, 10000],
numZoomLevels: 26,
allOverlays: true,
projection: new OpenLayers.Projection("EPSG:900913"),
displayProjection: new OpenLayers.Projection("EPSG:4326"),
controls:[
new OpenLayers.Control.Navigation(),
new OpenLayers.Control.PanZoomBar(),
new OpenLayers.Control.LayerSwitcher({'ascending':false}),
new OpenLayers.Control.ScaleLine(),
new OpenLayers.Control.MousePosition(),
new OpenLayers.Control.OverviewMap(),
new OpenLayers.Control.Attribution(),
new OpenLayers.Control.KeyboardDefaults()],};
map = new OpenLayers.Map('map_element', options);
var gsat = new OpenLayers.Layer.Google(
"Google Satellite",
{type: google.maps.MapTypeId.SATELLITE} );
map.addLayer(gsat);
gsat.mapObject.setTilt(0);
var kml = new OpenLayers.Layer.Vector("zahrada", {
projection: map.displayProjection,
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "kml/zahrada.kml",
format: new OpenLayers.Format.KML({
extractStyles: true,
extractAttributes: true,
})
})
});
map.addLayer(kml);
var vrstva_dve = new OpenLayers.Layer.Vector("vrstva_dve", {
projection: map.displayProjection,
strategies: [new OpenLayers.Strategy.Fixed()],
protocol: new OpenLayers.Protocol.HTTP({
url: "kml/vrstva_dve.kml",
format: new OpenLayers.Format.KML({
extractStyles: true,
extractAttributes: true,
})
})
});
map.addLayer(vrstva_dve);
select = new OpenLayers.Control.SelectFeature(kml); // here I tried ([kml, vrstva_dve]) , but still only layer kml is selectable
kml.events.on({
"featureselected": onFeatureSelect,
"featureunselected": onFeatureUnselect
});
map.addControl(select);
select.activate();
}
function onPopupClose(evt) {
select.unselectAll();
}
function onFeatureSelect(event) {
var feature = event.feature;
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;
}
}