openlayers格式json正在返回空响应text字符串

Question

在OpenLayers论坛上发布了一周的发布并没有收到对我的问题的回答，我决定在这里查看。我已经用谷歌搜索了Google和Google搜索谷歌，甚至找到了有关该主题的精彩教程，但写得很好，以至于Google Translate能够完美地翻译它。

gisandchips.org/2010/05/04/openlayers y-panoramio/

因此，我遵循了本教程，现在我正在尝试访问全景数据API来查询照片并将其显示在我的地图上。但是，我的代码失败了：

var panoramio = json.read（response.responseText）;

根据Firebug和Alert（Response.ResponSeText），我的ResponseText是一个空字符串...

在firebug中，我有get urlhttp://localhost/cgi-bin/proxy.cgi?url=http%3A%2F%2Fwww.panoramio.com%2Fmap%2Fget_panoramas.php%3Forder%3Dpopularity%26set%3Dfull%26from%3D0%26to%3D40%26minx%3D-20037508.3392%26miny%3D-20037508.3392%26maxx%3D20037508.3392%26maxy%3D20037508.3392%26size%3Dthumbnail

这向我展示了有效的JSON。而且我知道我的响应对象不是null的，因为警报（响应）表明它正在获得[对象XMLHTTPRequest

老实说，我没有想法。在尝试解析JSON之前，我试图解析XML，绝对没有运气。我真的很喜欢将RSS和API数据提取到我的地图上的想法。下面我附上代码，感谢您可以提供的任何反馈:)

谢谢，

Elshae

var map, popup, selectControl, selectedFeature;
var vectorLayer, panoramio_style;

Ext.onReady(function () {
    var options = {
        controls: [new OpenLayers.Control.Navigation()], //Needed to use GeoExt controls such as the zoomslider
        maxExtent: new OpenLayers.Bounds(-20037508.34, -20037508.34, 20037508.34, 20037508.34),
        units: 'm',
        allOverlays: false
    }

    this.map = new OpenLayers.Map(options);

    var ghyb = new OpenLayers.Layer.Google(
            "Google Hybrid",
            {type: google.maps.MapTypeId.HYBRID, numZoomLevels: 20}
    );

    var gmap = new OpenLayers.Layer.Google(
            "Google Streets", // the default
            {type: google.maps.MapTypeId.ROADMAP, numZoomLevels: 20}
    );

    var gphy = new OpenLayers.Layer.Google(
            "Google Physical",
            {type: google.maps.MapTypeId.TERRAIN, numZoomLevels: 20}
            // used to be {type: G_PHYSICAL_MAP}
    );

    var osm = new OpenLayers.Layer.OSM();

    map.addLayers([osm, gphy, gmap, ghyb]);

    OpenLayers.ProxyHost = "http://localhost/cgi-bin/proxy.cgi?url=";

    var mapPanel = new GeoExt.MapPanel({
        title: "Map",
        map: this.map,
        center: new OpenLayers.LonLat(93.9, 29.53).transform(new OpenLayers.Projection("EPSG:4326"),
                new OpenLayers.Projection("EPSG:900913")),
        zoom: 2,
        region: "center"
    });

    //Obtain Bbox coords
    var proj = new OpenLayers.Projection("EPSG:900913");
    var ext = mapPanel.map.getMaxExtent().transform(mapPanel.map.getProjectionObject(), proj);
    var minx = ext.left;
    var miny = ext.bottom;
    var maxx = ext.right;
    var maxy = ext.top;
    alert(minx + " " + miny + " " + maxx + " " + maxy);

    url = "http://www.panoramio.com/map/get_panoramas.php";
    var parameters = {
        order: 'popularity',
        set: 'full',
        from: 0,
        to: 40,
        minx: minx,
        miny: miny,
        maxx: maxx,
        maxy: maxy,
        size: 'thumbnail'
    }

    new Ext.Panel({
        width: 1800,
        height: 600,
        layout: "border",
        renderTo: document.body,
        items: [mapPanel]
    });

    OpenLayers.loadURL(url, parameters, this, showPhotos);
    //alert(OpenLayers.Request.XMLHttpRequest);

});

function showPhotos(response) {

    var json = new OpenLayers.Format.JSON();
    var panoramio = json.read(response.responseText); //Something is wrong here!!!
    var features = new Array(panoramio.photos.length);
    for (var i = 0; i < panoramio.photos.length; i++) {
        var upload_date = panoramio.photos[i].upload_date;
        var owner_name = panoramio.photos[i].owner_name;
        var photo_id = panoramio.photos[i].photo_id;
        var longitude = panoramio.photos[i].longitude;
        var latitude = panoramio.photos[i].latitude;
        var pheight = panoramio.photos[i].height;
        var pwidth = panoramio.photos[i].width;
        var photo_title = panoramio.photos[i].photo_title;
        var owner_url = panoramio.photos[i].owner_url;
        var owner_id = panoramio.photos[i].owner_id;
        var photo_file_url = panoramio.photos[i].photo_file_url;
        var photo_url = panoramio.photos[i].photo_url;

        var fpoint = new OpenLayers.Geometry.Point(longitude, latitude);

        var attributes = {
            'upload_date': upload_date,
            'owner_name': owner_name,
            'photo_id': photo_id,
            'longitude': longitude,
            'latitude': latitude,
            'pheight': pheight,
            'pwidth': pwidth,
            'pheight': pheight,
            'photo_title': photo_title,
            'owner_url': owner_url,
            'owner_id': owner_id,
            'photo_file_url': photo_file_url,
            'photo_url': photo_url
        }

        features[i] = new OpenLayers.Feature.Vector(fpoint, attributes);

    }//Outside for loop

    panoramio_style = new OpenLayers.StyleMap(OpenLayers.Util.applyDefaults({
        pointRadius: 7,
        fillColor: "red",
        fillOpacity: 1,
        strokeColor: "black",
        externalGraphic: "panoramio-marker.png"
    }, OpenLayers.Feature.Vector.style["default"]));

    vectorLayer = new OpenLayers.Layer.Vector("Panoramio Photos", {
        styleMap: panoramio_style
    });

    vectorLayer.addFeatures(features);

    this.map.addLayer(vectorLayer);

    selectControl = new OpenLayers.Control.SelectFeature(vectorLayer,
            {onSelect: onFeatureSelect, onUnselect: onFeatureUnselect});
    this.map.addControl(selectControl);
    selectControl.activate();
}//End showPhotos

// popups
function onPopupClose(evt) {
    selectControl.unselect(selectedFeature);
}

function onFeatureSelect(feature) {
    selectedFeature = feature;

    // HTML del PopUp
    var html = "some HTML I have here";

    popup = new OpenLayers.Popup.FramedCloud("chicken",
            feature.geometry.getBounds().getCenterLonLat(),
            null,
            html,
            null,
            true,
            onPopupClose);

    feature.popup = popup;
    this.map.addPopup(popup);
}

function onFeatureUnselect(feature) {
    this.map.removePopup(feature.popup);
    feature.popup.destroy();
    feature.popup = null;
}

Answer 1

看起来您已经撞到了 相同的原点政策. 。除非您使用 JSONP, ，或其他一些解决政策的技术。您的要求 www.panoramio.com 是问题所在，因为我认为您没有主持 www.panoramio.com :)

您可能需要检查Panoramio是否提供JSONP服务。否则，您可以查看以下堆栈溢出帖子，以获取一些流行的解决方案，以符合相同的来源策略（主要是JSONP，CORS和反向代理方法）：

• 规避相同原产政策的方法

和空 responseText 当大多数浏览器阻止第三方域的响应时，它们是典型的：

• xmlhttprequest的空响应text