CS50-Web-Programming-with-Python-and-JavaScript/lecture6/stoplight.html at master · dthinkcs/CS50-Web-Programming-with-Python-and-JavaScript · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
<!DOCTYPE html>
<html>
    <head>
        <script src="https://d3js.org/d3.v4.min.js"></script>
    </head>
    <body>
        <svg id="svg" style="width:100%; height:800px"/>
    </body>
    <script>

        const svg = d3.select('#svg');

        svg.append('rect')
           .attr('x', 100)
           .attr('y', 10)
           .attr('width', 200)
           .attr('height', 500)
           .style('fill', 'black');

        const red = svg.append('circle')
                       .attr('cx', 200)
                       .attr('cy', 100)
                       .attr('r', 75)
                       .style('fill', 'grey');

        const yellow = svg.append('circle')
                          .attr('cx', 200)
                          .attr('cy', 260)
                          .attr('r', 75)
                          .style('fill', 'grey');

        const green = svg.append('circle')
                         .attr('cx', 200)
                         .attr('cy', 420)
                         .attr('r', 75)
                         .style('fill', 'grey');

        red.on('click', () => {
            red.style('fill', 'red');
            yellow.style('fill', 'grey');
            green.style('fill', 'grey');
        });

        yellow.on('click', () => {
            red.style('fill', 'grey');
            yellow.style('fill', 'yellow');
            green.style('fill', 'grey');
        });

        green.on('click', () => {
            red.style('fill', 'grey');
            yellow.style('fill', 'grey');
            green.style('fill', 'green');
        });

    </script>
</html>