In D3 V4, how to use .ease(“bounce”) propertly?

问题

Here is my code:

<html>
<head>
<meta charset="UTF-8">
<title>circle</title>
</head>
 
<body>
    <script src="http://d3js.org/d3.v4.min.js"></script>
    <script> 
        var width = 400;    
        var height = 400;    
        var svg = d3.select("body")    
                    .append("svg")     
                    .attr("width",width)     
                    .attr("height",height);     

        var circle1 = svg.append("circle")  
                         .attr("cx", 100)  
                         .attr("cy", 100)   
                         .attr("r", 45) 
                         .style("fill","green");
        circle1.transition()
            .duration(1000)  //延迟1000ms
            .attr("cx", 300);

        var circle2 = svg.append("circle")
                         .attr("cx", 100)
                         .attr("cy", 100)
                         .attr("r", 45)
                         .style("fill","green");

        circle2.transition()
            .duration(1500)
            .attr("cx", 300)
            .style("fill", "red");

        var circle3 = svg.append("circle")
                         .attr("cx", 100)
                         .attr("cy", 100)
                         .attr("r", 45)
                         .style("fill","green");
        circle3.transition()
            .duration(2000)
            .transition()
            .ease("bounce")
            .attr("cx", 300)
            .style("fill", "red")
            .attr("r", 25);

    </script>     
</body>
</html>

When I learn how to use the .ease("bounce")in d3 v4.x, the error is always jump out in html:45. In the official introduction: .ease("bounce") now should be used like this:

d3.easeBounce(t)

but it also doesn't work, so I don't know how to modify it. Could you give me a good introduction? Thanks!

回答1:

The documentation on transition.ease([value]) tells us, that

The value must be specified as a function.

Therefore, you just need to pass in the easing function d3.easeBounce without actually calling it (note, that there are no parentheses following d3.easeBounce):

circle3.transition()
  .duration(2000)
  .transition()
  .ease(d3.easeBounce)   // Pass in the easing function

回答2:

I agree with Altocumulus's answer, but I try to get rid of one of the middle.transition(), and it will run well.

circle3.transition()
  .duration(2000)
  .ease(d3.easeBounce)

来源：https://stackoverflow.com/questions/40765051/in-d3-v4-how-to-use-easebounce-propertly

标签

javascript

d3.js