“marker.setVisible(false)"和“marker.setVisible(false)"有什么区别?和“marker.setMap(null)"在谷歌地图 v3 中? [英] What is the difference between "marker.setVisible(false)" and "marker.setMap(null)" in Google Maps v3?

问题描述

我想清除 Google 地图上的标记.

I want to clear a marker on Google Maps.

marker.setVisible(false) 和 marker.setMap(null) 有什么区别?

但我不知道，哪个是对的?

But I don't know, which is right?

推荐答案

这两种方法之间的区别似乎没有明确记录.但是，请注意以下几点:

The difference between the two methods does not seem to be clearly documented. However, note the following:

• 当您使用setMap(null) 时，您的标记将丢失对Map 的引用.如果您不保留对 Map 对象的引用，您将无法重新显示标记.

• When you use setMap(null), your marker will lose the reference to the Map. If you do not keep a reference to the Map object, you wouldn't be able to reshow the marker.

此外，setMap() 方法不会触发 visible_changed 事件，而 setVisible() 方法会触发 (如果可见性实际上已切换).

In addition, the setMap() method will not trigger the visible_changed event, while the setVisible() method does (if the visibility is actually toggled).

示例:

var map = new google.maps.Map(document.getElementById('map'), {
  zoom: 4,
  center: new google.maps.LatLng(-25.363, 131.044),
  mapTypeId: google.maps.MapTypeId.ROADMAP
});

var marker = new google.maps.Marker({
  position: new google.maps.LatLng(-25.363, 131.044), 
  map: map
}); 

google.maps.event.addListener(marker, 'visible_changed', function() {
  console.log('visible_changed triggered');
});

marker.setVisible(false); // visible_changed triggered
marker.setVisible(true);  // visible_changed triggered
marker.setMap(null);      // visible_changed not triggered
marker.setMap(map);       // visible_changed not triggered

我想当我们打算在地图上再次显示标记时，我们应该使用 setVisible(false) 方法，而当我们打算重新显示标记时，应该使用 setMap(null)不会再显示它了.

I guess we should be using the setVisible(false) method when we intend to reshow the marker again on the map, and the setMap(null) when we will not be showing it again.

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