我在下面有以下代码，其中位置未显示在地图上，经过 4 天的搜索，我仍然不知道为什么。有人能帮助我吗？我真的不知道为什么它不起作用。数据已从网络服务正确检索到我的 JavaScript，但地图变为空:(
任何帮助将不胜感激。提前致谢。
如果我在不从服务器获取数据的情况下更新几个点，如下例所示，它会起作用
var baseMapLayer = new ol.layer.Tile({
source: new ol.source.OSM()
});
var map = new ol.Map({
target: 'map',
layers: [ baseMapLayer],
view: new ol.View({
center: ol.proj.fromLonLat([-9.294444444,38.70833333]), // Cordinates of EDISOFT
zoom: 7 //Initial Zoom Level
})
});
var myMarkerFeatures = [];
//Adding a marker on the map near sines
var marker1 = new ol.Feature({
geometry: new ol.geom.Point(
ol.proj.fromLonLat([-9.294444444,37.70833333])
), // Cordinates of EDISOFT Thales in Paço de Arcos
});
marker1.setStyle(new ol.style.Style({
image: new ol.style.Icon(({
crossOrigin: 'anonymous',
src: 'AISSymbols/cargo-ship.png',
scale: 0.30
})),
text: new ol.style.Text({
text: '501',
fill: new ol.style.Fill({color: 'black'}),
stroke: new ol.style.Stroke({color: 'yellow', width: 1}),
offsetX: -20,
offsetY: 20
})
}));
marker1.setId(501);
//Adding a marker on the map near EDIOSFT
var marker2 = new ol.Feature({
geometry: new ol.geom.Point(
ol.proj.fromLonLat([-9.294444444,38.70833333])
), // Cordinates of 1 degree to the west of EDISOFT location
});
marker2.setStyle(new ol.style.Style({
image: new ol.style.Icon(({
crossOrigin:
'anonymous',
src: 'AISSymbols/AIS_Vessel.svg',
rotation: Math.PI / 4.0,
scale: 0.30
})),
text: new ol.style.Text({
text: '502',
fill: new ol.style.Fill({color: 'black'}),
stroke: new ol.style.Stroke({color: 'red', width: 1}),
offsetX: -20,
offsetY: 20
})
}));
marker2.setId(502);
//myMarkerFeatures = [marker1, marker2];
var vectorSource = new ol.source.Vector({
features: myMarkerFeatures
});
myMarkerFeatures.push(marker1);
myMarkerFeatures.push(marker2);
//Adding a marker on the map near shore
var markerVectorLayer = new ol.layer.Vector({
source: vectorSource,
});
map.addLayer(markerVectorLayer);
var marker = new ol.Feature({
geometry: new ol.geom.Point(
ol.proj.fromLonLat([-9.694444444,38.70833333])
), // Cordinates of New York's City Hall
});
marker.setStyle(new ol.style.Style({
image: new ol.style.Icon(({
crossOrigin:
'anonymous',
src: 'AISSymbols/AIS_Vessel.svg',
rotation: Math.PI / 1.0,
scale: 0.30
})),
text: new ol.style.Text({
text: '503',
fill: new ol.style.Fill({color: 'black'}),
stroke: new ol.style.Stroke({color: 'back', width: 1}),
offsetX: -20,
offsetY: 20
})
}));
marker.setId(503);
myMarkerFeatures.push(marker);
map.renderSync();
vectorSource.clear(true);
vectorSource.addFeatures(myMarkerFeatures);
//////////////////////////////////////////////////////////
vectorSource.clear(true);
for (var i=0; i<myMarkerFeatures.length;i++){
if (myMarkerFeatures[i].getId() === 502){
myMarkerFeatures[i].set('geometry', new ol.geom.Point(getPointFromLongLat(-10.694444444,38.70833333)));
//myMarkerFeatures[i].getGeometry().setCoordinates([-10.694444444,38.70833333]);
//myMarkerFeatures[i].getGeometry().setCoordinates(getPointFromLongLat(-10.694444444, 38.70833333));
}else if (myMarkerFeatures[i].getId() === 501){
myMarkerFeatures[i].set('geometry', new ol.geom.Point(getPointFromLongLat(-9.294444444,36.70833333)));
//myMarkerFeatures[i].getGeometry().setCoordinates([-9.294444444,36.70833333]);
//myMarkerFeatures[i].getGeometry().setCoordinates(getPointFromLongLat(-9.294444444, 36.70833333));
} else if (myMarkerFeatures[i].getId() === 503){
myMarkerFeatures[i].set('geometry', new ol.geom.Point(getPointFromLongLat(-9.694444444,39.70833333)));
//myMarkerFeatures[i].getGeometry().setCoordinates([-9.694444444,39.70833333]);
//myMarkerFeatures[i].getGeometry().setCoordinates(getPointFromLongLat(-9.694444444, 39.70833333));
} else {
alert('Dummy points found');
}
};
//map.renderSync();
vectorSource.addFeatures(myMarkerFeatures);
function getPointFromLongLat (long, lat) {
return ol.proj.transform([long, lat], 'EPSG:4326', 'EPSG:3857')
}
var baseMapLayer = new ol.layer.Tile({
source: new ol.source.OSM()
});
var map = new ol.Map({
target: 'map',
layers: [baseMapLayer],
view: new ol.View({
center: ol.proj.fromLonLat([-9.294444444, 38.70833333]), // Cordinates of EDISOFT
zoom: 7 //Initial Zoom Level
})
});
var aisMarkerFeatures = [];
var vectorSource = new ol.source.Vector({
features: aisMarkerFeatures //add an array of features
});
var vectorLayer = new ol.layer.Vector({
source: vectorSource
});
map.addLayer(vectorLayer);
function addMarker(MMSI, lon, lat, COG) {
var found = false;
for(var i = 0; i < aisMarkerFeatures.length; i++) {
if (aisMarkerFeatures[i].getId() === MMSI) {
aisMarkerFeatures[i].set('geometry', new ol.geom.Point(getPointFromLongLat(lon, lat)));
aisMarkerFeatures[i].setStyle(new ol.style.Style({
image: new ol.style.Icon(({
crossOrigin:
'anonymous',
src: 'AISMarkers/cargo-ship.png',
rotation: Math.PI * COG / 180.0,
scale: 0.30
})),
text: new ol.style.Text({
text: MMSI,
fill: new ol.style.Fill({ color: 'black' }),
stroke: new ol.style.Stroke({ color: 'black', width: 1 }),
offsetX: -20,
offsetY: 20
})
}));
found = true;
break;
}
}
if (found == false) {
var markerGeometry = new ol.geom.Point(ol.proj.fromLonLat([lon, lat]));
var markerFeature = new ol.Feature({
geometry: markerGeometry
});
markerFeature.setId(MMSI);
markerFeature.setStyle(new ol.style.Style({
image: new ol.style.Icon(({
crossOrigin:
'anonymous',
src: 'AISMarkers/cargo-ship.png',
rotation: Math.PI * COG / 180.0,
scale: 0.30
})),
text: new ol.style.Text({
text: MMSI,
fill: new ol.style.Fill({ color: 'black' }),
stroke: new ol.style.Stroke({ color: 'black', width: 1 }),
offsetX: -20,
offsetY: 20
})
}));
aisMarkerFeatures.push(markerFeature);
}
};
function getPointFromLongLat(long, lat) {
return ol.proj.transform([long, lat], 'EPSG:4326', 'EPSG:3857')
}
window.setInterval(function () {
//clean the layer from any existing markers
vectorSource.clear(true);
$.ajax({
url: 'http://localhost/aisdataretriever/aisdataretriever.asmx/TransferAISPosition',
type: 'POST',
cache: false,
dataType: 'json',
success: function (aisdata) {
$.each(aisdata, function (recordCount, aisship) {
var createMarker = addMarker(aisship.MMSI, aisship.Longitude, aisship.Latitude, aisship.COG);
});
//and here add the newly created features to the layer
vectorSource.addFeatures(aisMarkerFeatures);
}, error: function () {
console.log("Connection Failed");
}
});
}, 5000);
地图意外显示没有点