javascript - 为什么我的谷歌地图事件监听器无法正常工作？

Question

我正在尝试处理每个标记的鼠标悬停监听器(有 30 个标记)并显示这些标记的信息窗口。我为每个标记创建了监听器，但是当我的鼠标悬停在某个标记上时，它始终显示最后一个标记的信息窗口。总而言之，我听不到其他标记。任何帮助，将不胜感激。提前致谢，这是我的代码:

var listeners = [];
for(var i = 0; i < markers.length; i++){
  var marker = markers[i];
  var contentString = contents[i];
  listeners[i] = new google.maps.event.addListener(marker, 'mouseover', function() {
    var hideInfoWindows = function(){
        for (var j = 0; j < util.Common.infowindows.length; j++) {
          util.Common.infowindows[j].close(); 
        }
    }
    var addInfoWindow = function(){
        var infowindow = new google.maps.InfoWindow({
            content: contentString
        });
        //hideInfoWindows();
        util.Common.infowindows.push(infowindow);
        infowindow.open(util.Common.googlemap,marker);
    }
    addInfoWindow();
  });
}

我也在使用js cluster library但我认为问题与此无关。

Answer 1

我认为你的问题可能是你没有在循环内使用闭包，并且当事件监听器被触发时，marker和contentString变量指向到最后一个标记。

尝试像这样重写循环:

var listeners = [];
for(var i = 0; i < markers.length; i++){
    (function(index){ //create a closure, variable 'index' will take its value from variable i, but won't be affected by changed i in the outer scope
        var marker = markers[index]; //use this scope's index variable instead of i
        var contentString = contents[index]; //use this scope's index variable instead of i
        listeners[index] = new google.maps.event.addListener(marker, 'mouseover', function() {
            var hideInfoWindows = function(){
                for (var j = 0; j < util.Common.infowindows.length; j++) {
                    util.Common.infowindows[j].close();
                }
            };
            var addInfoWindow = function(){
                var infowindow = new google.maps.InfoWindow({
                    content: contentString
                });
                //hideInfoWindows();
                util.Common.infowindows.push(infowindow);
                infowindow.open(util.Common.googlemap,marker);
            };
            addInfoWindow();
        });
    })(i);
}