HERE 地图 removeEventListener 不起作用

HERE maps removeEventListener doesn't work

我正在尝试从地图中删除“addEventListerner”,但它不起作用有我的代码:

function dbltapzoom(){
    alert("Remove");
}

 map.addEventListener('pointerdown', function (evt) {
         var coord = map.screenToGeo(evt.currentPointer.viewportX,
         evt.currentPointer.viewportY);

         polygonStroke.setGeometry(coord);
         polygonStroke.setVisibility(true);
         locationVertices.push(polygonStroke);
         map.addObject(polygonStroke);    
},false);

map.addEventListener('dbltap', function () { 
          map.removeEventListener('pointerdown',dbltapzoom,false);
});

老实说,我不知道该怎么做。任何帮助和解释我做错了什么都会很好。感谢您的帮助:)

您只能删除同一个注册的侦听器。就像您在 pointerdown 上注册到映射列表器 handlepointerdown 一样,您只能删除 handlepointerdown,不能在同一个监听器

中删除 dbltapzoom
function dbltapzoom(){
    alert("Remove");
}

function handlepointerdown(evt) {
         var coord = map.screenToGeo(evt.currentPointer.viewportX,
         evt.currentPointer.viewportY);

         polygonStroke.setGeometry(coord);
         polygonStroke.setVisibility(true);
         locationVertices.push(polygonStroke);
         map.addObject(polygonStroke);    
}

 map.addEventListener('pointerdown', handlepointerdown,false);

map.addEventListener('dbltap', function () { 
          map.removeEventListener('pointerdown',handlepointerdown,false);
});