maps - 有没有办法根据缩放级别更改图标图像？ (传单.js)

Question

我正在为 Web 应用程序制作一个区域绘制工具，我使用标记作为 anchor ，用户可以使用它来更改多边形的形状。

这是我到目前为止。 http://demos.nodeline.com/leaflet_development/

repo 在 https://github.com/SpencerCooley/Leaflet_development

$(document).ready(function(){

var map, cloudmade, sanAntonio, polygonPoints  


 map = new L.Map('map');

 cloudmade = new L.TileLayer('http://{s}.tile.cloudmade.com/d4334cd6077140e3b92ccfae2b363070/997/256/{z}/{x}/{y}.png', {
    attribution: 'Map data &copy; <a href="http://openstreetmap.org">OpenStreetMap</a> contributors, <a href="http://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>, Imagery © <a href="http://cloudmade.com">CloudMade</a>',
    maxZoom: 18
});


 sanAntonio = new L.LatLng(29.4238889, -98.4933333); // geographical point (longitude and latitude)


 map.setView(sanAntonio, 13).addLayer(cloudmade);




polygonPoints = [];

var polygon = new L.Polygon(polygonPoints);
map.addLayer(polygon);

map.on('click', function(e) {  


  var marker = new L.Marker(e.latlng, {draggable:true});
  polygonPoints.push(e.latlng);
  var markerId = polygonPoints.length -1 
  map.addLayer(marker);
  polygon.setLatLngs(polygonPoints);



  marker.on('drag', function(){
    var locationWhileDrag = marker.getLatLng();
    $('#first_marker').val(locationWhileDrag);
    polygonPoints.splice(markerId,1,locationWhileDrag);
    polygon.setLatLngs(polygonPoints);
  });      



});







});

当用户放大到街道级别时，我只希望标记为正常大小。当您缩小正常大小的标记时，会完全淹没多边形。我查看了文档，但找不到任何关于此的信息。

我主要是在寻找建议/头脑 Storm 。我在想也许有一种方法可以检测您当前处于哪种缩放状态？如果是这样，我可以使用 if 语句来更改图标。

Answer 1

好的，所以我找到了一些方法并想出了这个:

//this sets up an icon to be replaced on redraw. 
var MyIcon = L.Icon.extend({
    iconUrl: 'marker.png',
    iconSize: new L.Point(10, 16),
    shadowSize: new L.Point(10, 16),
    iconAnchor: new L.Point(10, 16)
});

var icon = new MyIcon();

//When view resets use the smaller icon if zoom level is less than 13
map.on('viewreset', function(){
    if(map.getZoom() < 13){
        marker.setIcon(icon);
    }
});

setIcon() 方法没有在文档中，我在谷歌论坛中找到了它并且有效。我制作了一个较小的图标，我基本上只是在缩放级别小于 13 时替换原始图标。我将要实现不同缩放级别的不同标记现在可以使标记“更远”效果。

这是修改后的代码。

$(document).ready(function(){

var map, cloudmade, sanAntonio, polygonPoints  

map = new L.Map('map');

cloudmade = new L.TileLayer('http://{s}.tile.cloudmade.com/d4334cd6077140e3b92ccfae2b363070/997/256/{z}/{x}/{y}.png', {
    attribution: 'Map data &copy; <a href="http://openstreetmap.org">OpenStreetMap</a> contributors, <a href="http://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>, Imagery © <a href="http://cloudmade.com">CloudMade</a>',
    maxZoom: 18
});

sanAntonio = new L.LatLng(29.4238889, -98.4933333); // geographical point (longitude and latitude)

map.setView(sanAntonio, 13).addLayer(cloudmade);

polygonPoints = [];

var polygon = new L.Polygon(polygonPoints);
map.addLayer(polygon);

map.on('click', function(e) {  
    //this sets up an icon to be replaced when redraw. 
    var MyIcon = L.Icon.extend({
        iconUrl: 'marker.png',
        iconSize: new L.Point(10, 16),
        shadowSize: new L.Point(10, 16),
        iconAnchor: new L.Point(10, 16)
    });

    var icon = new MyIcon(); 
    //this sets up an icon to be replaced when redraw.

    var marker = new L.Marker(e.latlng, {draggable:true});
    polygonPoints.push(e.latlng);
    var markerId = polygonPoints.length -1 
    map.addLayer(marker);
    polygon.setLatLngs(polygonPoints);

    marker.on('drag', function(){
        var locationWhileDrag = marker.getLatLng();
        $('#first_marker').val(locationWhileDrag);
        polygonPoints.splice(markerId,1,locationWhileDrag);
        polygon.setLatLngs(polygonPoints);
    });      

    //When view resets use the small icon if zoom level is less than 13
    map.on('viewreset', function(){
        if(map.getZoom() < 13){
            marker.setIcon(icon);
        }
    });
});

});

这是演示:
http://demos.nodeline.com/leaflet_development/