在bencoding.map中替代KML的Appcelerator

Question

我正在更新一个曾经使用"bencoding.map“https://github.com/benbahrenburg/benCoding.Map/blob/master/documentation/index.md的应用程序。

现在"bencoding.map“被弃用了，所以我更新为使用原生的钛地图特性。

然而，我现在遇到了一个问题，来自"bencoding.map“的"addKML”在Titanium map api中不可用。

有人知道我可以用什么来替换KML功能吗？代码如下：

    function onkmlCompleted(){
        Ti.API.info("onkmlCompleted");
        Ti.API.info("onkmlCompleted"+JSON.stringify(mapLoadingWindow));
        mapLoadingWindow.close({animated:false});
        mapView.removeEventListener('kmlCompleted',onkmlCompleted);
    };

    mapView.addEventListener('kmlCompleted',onkmlCompleted);

    mapView.addKML({
        path:"some_file.kml", //Path to our kml file
        tag : 55, //Integer value used as the tag for all polygons and annotations. If you want use remove you need to set this to a known value.
        flyTo:false, //Will set your zoom to show all of your points added (false by default)        
        //Contains all of the details used to process overlays from your KML file
        overlayInfo:{
            title:'my kml batch key', //This identifies all of the overlay elements in your kml file. This is also used for delete or query operations.
            alpha:0.5, //Alpha value of your overlays
            lineWidth:1.2, //Line Width of your overlays
            strokeColor:'#000', //Stroke Color of your overlays
            color:'yellow', //Sets the color of all your overlays ( if left off, a random color will be selected)
            useRandomColor:true, //If true, a random color will be selected, this overrides the color provided if true              
        }
    });

Answer 1

一种选择是将kml数据转换为JSON，然后根据数据需要，通过映射模块的方法(如createPolygon、createPolyline等)将数据添加到本机Titanium Map。

我已经使用togeojson Node.js模块做到了这一点。从Titital6开始，我们现在可以直接从我们的项目中访问Node模块。假设您使用的是一个合金项目：

cd MyProject/app/assets
npm install togeojson

这还将安装一些其他依赖模块，包括我们也可以使用的xmldom。

获取一些sample KML LineString data并将其放在MyProjects/app/assets中，然后我们可以使用togeojson模块对其进行转换。这会让我们走到一半。Titanium模块不会说GeoJSON，但是因为GeoJSON只是JSON，所以我们可以遍历它并获取所需的数据，然后将其提供给相关的Map模块方法。

下面是通过向地图的createPolyline方法发送KML数据来完成所有这些操作的示例。假设这个合金index.js控制器有一个带有' map‘id的映射视图：

//the titanium map module
var Map = require('ti.map');
//the node module we installed
var togeojson = require('togeojson');
//a dependency of togeojson which we will also use
var DOMParser = require('xmldom').DOMParser;

//with out data file in apps/assets
var file = Ti.Filesystem.getFile(Ti.Filesystem.resourcesDirectory, "linestring.kml");
var kml = file.read().text;

//the module requires the xml data in XML DOM, so we parse it first
var xml = (new DOMParser()).parseFromString(kml, 'text/xml');

//convert the kml to GeoJSON
var converted = togeojson.kml(xml);

//Here, we iterate through the GeoJSON file and pull out the coordinates to use to 
//create our Map polygons, polylines, etc.  Your implementation will vary depending
//on the data you are reading
converted.features.forEach(function(feature){
    if(feature.geometry.type === 'LineString')
    $.map.addPolyline(Map.createPolyline({
        points: feature.geometry.coordinates,
        strokeColor: '#ff0000',
        strokeWidth: '2'
    }));
});

$.map.setRegion({
    latitude: 37.824664,
    latitudeDelta: 0.002,
    longitude: -122.364383,
    longitudeDelta: 0.002
});