为什么鼠标悬停事件不会在谷歌地图中调度折线？

Question

我有一个复杂的流程,我要为地图上的每条折线附加鼠标悬停事件.附加事件的代码很简单:

google.maps.event.addListener(polyline, "mouseover", function() {
    console.log('event fired');

});

但事件是附加到少数折线而不是其他折线.可能是什么原因？

编辑

以下是在上述代码之前的一些代码,用于定义折线:

this.polyline = new google.maps.Polyline({
    path : [fromPosition, toPosition],
    strokeColor : '#CCCCCC',
    strokeOpacity : 1.0,
    strokeWeight : 2
});

var polyline = this.polyline;

编辑2012年4月5日

以下是产生问题的代码,请解释它为什么会发生并推荐任何解决方案.谢谢

function Link(from, to) {
    this.from = from;
    this.to = to;
}   

Link.prototype.show = function() {
    this.line = new google.maps.Polyline({
        path : [this.from, this.to],
        strokeColor : "#0000FF",
        strokeOpacity : 0.5,
        strokeWeight : 6
    });

    this.line.setMap(map);    
    google.maps.event.addListener(this.line, 'mouseover', function() {
        this.line.setOptions({
            strokeOpacity : 1
        });
    });

    google.maps.event.addListener(this.line, 'mouseout', function() {
        this.line.setOptions({
            strokeOpacity : 0.5
        });
    });
}

var links = [];
var link2 = new Link(new google.maps.LatLng(-3.5999999999999996, 23.4), new google.maps.LatLng(-4.5, 23.4)), link1 = new Link(new google.maps.LatLng(-3.5999999999999996, 23.4), new google.maps.LatLng(-3.5999999999999996, 18));
links.push(link1);
links.push(link2);

// I've a long list of links, so I'll prefer a loop
for(var i = 0; i < links.length; i++) {
    links[i].show();
}

JSFiddle演示:http://jsfiddle.net/wasimbhalli/9bg6x/

Answer 1

• 演示: http ://jsfiddle.net/kbngxku9/

 var map;

 function initialize() {

   var mapOptions = {
     center: new google.maps.LatLng(-3, 23),
     zoom: 5,
     mapTypeId: google.maps.MapTypeId.ROADMAP
   };

   map = new google.maps.Map(document.getElementById('mapcanvas'), mapOptions);

   var bounds = [];
   var bounds_group_1 = [new google.maps.LatLng(-3.5999999999999996, 23.4), new google.maps.LatLng(-4.5, 23.4)],
     bounds_group_2 = [new google.maps.LatLng(-3.5999999999999996, 23.4), new google.maps.LatLng(-3.5999999999999996, 18)];
   bounds.push(bounds_group_1);
   bounds.push(bounds_group_2);

   for (var i = 0; i < bounds.length; i++) {
     addPolylineSegment(bounds[i]);
   }
 }

 function addPolylineSegment(bounds) {

   // optionally you can put each polyline
   // segment into an array to later use...

   var polyline;

   polyline = new google.maps.Polyline({
     path: bounds,
     strokeColor: "#0000FF",
     strokeOpacity: 0.5,
     strokeWeight: 6
   });

   polyline.setMap(map);

   // attach event listener to each segment...
   google.maps.event.addListener(polyline, 'mouseover', function(event) {
     this.setOptions({
       strokeOpacity: 1
     });
   });

   google.maps.event.addListener(polyline, 'mouseout', function(event) {
     this.setOptions({
       strokeOpacity: 0.5
     });
   });
 }
 google.maps.event.addDomListener(window, 'load', initialize);

Answer 2

我设法使用下面描述的方法解决了这个问题。如果我理解正确的话，将侦听器附加到折线的循环实际上不会以这种方式“附加”到折线，而是需要一个包含折线和侦听器的新类实例。这样，每条折线都有自己的侦听器。

请参阅下面的解释。

编辑2012年4月5日

这也是代码实际运行的粗略 JSFiddle 演示。链接到 JSFiddle 演示

function initialize() {

    // initialize Google Maps canvas normally

    var polylines = [];

    // Data set of the polylines you want to present on the map, 
    // e.g. [ { lat:"...",lon:"..." }, ...]

    var polylineData = [{ ... }] 

    for ( i in polylineData ) {
         var line = new google.maps.Polyline({ 
             path: [/*coordinates as google.maps.LatLng objects*/] 
         });

         // Create a new myPolyLineClass instance that contains the polyline data
         // and push it to polylines array.

         polylines.push(new myPolyLineClass(line));
    }

    // Set all the polylines and their individual listeners on map

    for ( i in polylines) {
        polylines[i].line.setMap(map);
    }
}

function MyPolylineClass(lineData) {
    this.line = lineData;

    // + all other data you want the polylines to contain

    // Add listeners using google.maps.event.addListener to all class instances
    // when they are constructed.

    // for instance:

    google.maps.event.addListener(line, 'mouseover', function() {
            line.setOptions({ [options you want to set when area is hovered 
            and selected] });
    });

    // Add listeners also for when polyline is not hovered anymore, respectively,
    // and other methods you might want to call when polylines are being interacted with.
};

希望这可以帮助！

干杯