Bigger area for hovering multiple small circles

问题

I currently have a map. On this map I several small circles/dots created with border-radius. Hovering a dot animates the dot + other stuff.

MY ISSUE:
Right now I have to be VERY precise to hover a dot because it's so small.

Im wondering if its possible to create a bigger invisible hitzone hover area or similar surrounding the dot, thus making it easier to interact with the dot?

Here is an example :

$("#map-container").find(".dot-item")
	.mouseenter(function() {
		console.log("over");
  
      $(this).css("width","10");
      $(this).css("height","10");
	})
	.mouseleave(function() {
		console.log("out");
  
      $(this).css("width","5");
      $(this).css("height","5");
	}).on("click", function(e) {
		console.log("click");
});

#wrapper {
	position: relative;
	width: 500px;
	height: 500px;
  background-color: gray;
}

.dot-item {
  position: absolute;
  border-radius: 50%;
  width: 5px;
  height: 5px;
  background-color: red;
  cursor: pointer;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="wrapper">
  <div id="map-container">
    <div class="dot-item" style="top: 100px; left: 100px;"></div>
    <div class="dot-item" style="top: 200px; left: 200px;"></div>
    <div class="dot-item" style="top: 210px; left: 210px;"></div>
    <div class="dot-item" style="top: 400px; left: 400px;"></div>
  </div>
</div>

回答1:

You can create a bigger hover area with a transparent pseudo element positioned over the dots with :

.dot-item:before{
  content:'';
  position:absolute;
  top:-300%; left:-300%;
  width:700%; height:700%;
  border-radius:50%;
}

And here is the full code :

$("#map-container").find(".dot-item")
  .mouseenter(function() {
    console.log("over");

    $(this).css("width", "10");
    $(this).css("height", "10");
  })
  .mouseleave(function() {
    console.log("out");

    $(this).css("width", "5");
    $(this).css("height", "5");
  }).on("click", function(e) {
    console.log("click");
  });

#wrapper {
  position: relative;
  width: 500px;
  height: 500px;
  background-color: gray;
}
.dot-item {
  position: absolute;
  border-radius: 50%;
  width: 5px;
  height: 5px;
  background-color: red;
  cursor: pointer;
}
.dot-item:before {
  content: '';
  position: absolute;
  top: -300%;
  left: -300%;
  width: 700%;
  height: 700%;
  border-radius: 50%;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="wrapper">
  <div id="map-container">
    <div class="dot-item" style="top: 100px; left: 100px;"></div>
    <div class="dot-item" style="top: 200px; left: 200px;"></div>
    <div class="dot-item" style="top: 210px; left: 210px;"></div>
    <div class="dot-item" style="top: 400px; left: 400px;"></div>
  </div>
</div>

Sizes are probably excessive but you get the idea.

回答2:

You can use a positioned pseudo-element to achieve this.

I added a border for visual clarify but this would, of course, not be in the final product.

$("#map-container").find(".dot-item")
  .mouseenter(function() {
    console.log("over");

    $(this).css("width", "10");
    $(this).css("height", "10");
  })
  .mouseleave(function() {
    console.log("out");

    $(this).css("width", "5");
    $(this).css("height", "5");
  }).on("click", function(e) {
    console.log("click");
  });

#wrapper {
  position: relative;
  width: 500px;
  height: 500px;
  background-color: gray;
}
.dot-item {
  position: absolute;
  border-radius: 50%;
  width: 5px;
  height: 5px;
  background-color: red;
  cursor: pointer;
  z-index: 2;
}
.dot-item:after {
  content: "";
  width: 500%;
  height: 500%;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  position: absolute;
  z-index: -1;
  border: 1px solid red;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="wrapper">
  <div id="map-container">
    <div class="dot-item" style="top: 100px; left: 100px;"></div>
    <div class="dot-item" style="top: 200px; left: 200px;"></div>
    <div class="dot-item" style="top: 210px; left: 210px;"></div>
    <div class="dot-item" style="top: 400px; left: 400px;"></div>
  </div>
</div>

回答3:

By handling hover states in CSS, you can add a single element to the .dot-item like so:

<div class="dot-item" style="top: 100px; left: 100px;"><span></span></div>

Then style the two to allow you to control the hit box with .dot-item as a container:

.dot-item {
  position: absolute;
  border-radius: 50%;
  width: 25px;
  height: 25px;
  cursor: pointer;
}
.dot-item > span{
  display: block;
  border-radius: 50%;
  width: 5px;
  height: 5px;
  margin: 10px;
  background-color: red;
}
.dot-item:hover > span{
  width: 10px;
  height: 10px;
  margin: 7px;
}

See it in action here: http://codepen.io/anon/pen/azdaep

来源：https://stackoverflow.com/questions/27379476/bigger-area-for-hovering-multiple-small-circles