javascript - 选择时 d3 堆栈条形图的边框

Question

尝试为 d3 堆栈条形图中的选定条形图实现边框。这里第一个栏的顶部边框稍微落后于第二个栏。如何避免这种情况？

var svg, height, width, margin, parentWidth, parentHeight;

// container size
parentWidth = 700;
parentHeight = 500;
margin = {top: 50, right: 20, bottom: 35, left: 30};
width = parentWidth - margin.left - margin.right;
height = parentHeight - margin.top - margin.bottom;

var selectedSection = window.sessionStorage.getItem('selectedSection');

// data
var dataset = [{"label":"DEC","Set Up":{"count":12,"id":1,"label":"Set Up","year":"2016","graphType":"setup"},"Not Set Up":{"count":12,"id":0,"label":"Not Set Up","year":"2016","graphType":"setup"}},{"label":"JAN","Set Up":{"count":6,"id":1,"label":"Set Up","year":"2017","graphType":"setup"},"Not Set Up":{"count":21,"id":0,"label":"Not Set Up","year":"2017","graphType":"setup"}},{"label":"FEB","Set Up":{"count":1,"id":1,"label":"Set Up","year":"2017","graphType":"setup"},"Not Set Up":{"count":2,"id":0,"label":"Not Set Up","year":"2017","graphType":"setup"}},{"label":"MAR","Set Up":{"count":0,"id":1,"label":"Set Up","year":"2017","graphType":"setup"},"Not Set Up":{"count":0,"id":0,"label":"Not Set Up","year":"2017","graphType":"setup"}},{"label":"APR","Set Up":{"count":0,"id":1,"label":"Set Up","year":"2017","graphType":"setup"},"Not Set Up":{"count":0,"id":0,"label":"Not Set Up","year":"2017","graphType":"setup"}}];

// x cord
var x = d3.scale.ordinal()
    .rangeRoundBands([0, width], 0.2);

// color helper
var colorRange = d3.scale.category20();
var color = d3.scale.ordinal()
    .range(colorRange.range());

// x axis
var xAxis = d3.svg.axis()
    .scale(x)
    .orient('bottom');

var colors = ['#50BEE9', '#30738C'];

// Set SVG
svg = d3.select('#chart')
  .append('svg')
  .attr('width', width + margin.left + margin.right)
  .attr('height', height + margin.top + margin.bottom )
  .attr('class', 'setup')
  .append('g')
  .attr('transform', 'translate(' + margin.left + ',' + margin.top + ')');

color.domain(d3.keys(dataset[0]).filter(function(key) { return key !== 'label'; }));

dataset.forEach(function(d) {
  var y0 = 0;
  d.values = color.domain().map(function(name) { 
    return {
      name: name, 
      y0: y0, 
      y1: y0 += +d[name].count, 
      patientStatus:d[name].id,
      graphType:d[name].graphType,  
      fromDate:{
        month:d.label,
        year:d[name].year
      },
      toDate:{
        month:d.label,
        year:d[name].year
      }  
    }; 
  });
  d.total = d.values[d.values.length - 1].y1;
});

var y = d3.scale.linear()
    .domain([0, d3.max(dataset, function(d) {  
    return d.total;
  })])
    .range([height, 0]);

var ticks = y.ticks(),
    lastTick = ticks[ticks.length-1];    
var newLastTick = lastTick + (ticks[1] - ticks[0]);  
if (lastTick<y.domain()[1]){
  ticks.push(lastTick + (ticks[1] - ticks[0]));
}

// adjust domain for further value
y.domain([y.domain()[0], newLastTick]);

// y axis
var yAxis = d3.svg.axis()
    .scale(y)
    .orient('left')
    .tickSize(-width, 0, 0) 
    .tickFormat(d3.format('d'))
    .tickValues(ticks);

x.domain(dataset.map(function(d) { return d.label; }));
y.domain([0, d3.max(dataset, function(d) { return d.total; })]);

svg.append('g')
  .attr('class', 'x axis')
  .attr('transform', 'translate(0,' + height + ')')
  .call(xAxis);

svg.append('g')
  .attr('class', 'y axis')
  .call(yAxis);

var bar = svg.selectAll('.label')
    .data(dataset)
    .enter().append('g')
    .attr('class', 'g')
    .attr('id', function(d, i) {
    return i;
  })
    .attr('transform', function(d) { return 'translate(' + x(d.label) + ',0)'; });

var barEnter = bar.selectAll('rect')
    .data(function(d) { return d.values; })
    .enter();

barEnter.append('rect')
  .attr('width', x.rangeBand())
  .attr('y', function(d) { 
    return y(d.y1); 
    })
  .attr('class', function(d, i){
    return 'bar';
    })
  .attr('height', function(d) { return y(d.y0) - y(d.y1); })
  .style('fill', function(d,i) { return colors[i]; })
  .on('click', function(d, i) {
    d3.selectAll('.bar').classed('selected', false);
    d3.select(this)
      .classed('bar selected', true);  
    });

barEnter.append('text')
  .text(function(d) { 
    var calcH = y(d.y0) - y(d.y1);
    var inText = (d.y1-d.y0);
    if(calcH >= 20) {
      return inText;
    } else {
      return '';
    }
})
.attr('class','inner-text')
.attr('y', function(d) { return y(d.y1)+(y(d.y0) - y(d.y1))/2 + 5; })
.attr('x', function(){
  return (x.rangeBand()/2) - 10;
}); 

svg
  .select('.y')
  .selectAll('.tick')
  .filter(function (d) { 
    return d % 1 !== 0;    
    })
  .style('display','none');

svg
  .select('.y')
  .selectAll('.tick')
  .filter(function (d) { 
    return d === 0;    
    })
  .select('text')
  .style('display','none');

JSFiddle

JSFiddle with d3 v4

Answer 1

在 SVG 中，就像真正的画家在白色 Canvas 上泼墨一样，最后绘制的元素保留在最上面。

现在，您看到的行为是预期的行为，因为每个堆积条(矩形)位于不同的 <g> 中。元素和组当然在 SVG 结构中具有给定的顺序。

解决方案只涉及一行:

d3.select(this.parentNode).raise();

此行所做的是选择被单击的矩形组并将其提升(即，将其在 DOM 树中向下移动)，以便该组位于所有其他组之上。根据 API，raise() :

Re-inserts each selected element, in order, as the last child of its parent. (emphasis mine)

“向下移动”、“在最前面” 和“成为最后一个 child ” 可能有点令人困惑并且看起来很矛盾，但这是解释。鉴于此 SVG 结构:

<svg>
    <foo></foo>
    <bar></bar>
    <baz></baz>
</svg>

<baz> ，作为最后一个元素，是 last 绘制的元素，它是 SVG 中视觉上位于顶部的元素。因此，提升一个元素意味着在 SVG 树结构中将其向下移动，但在视觉上将其向上移动。

这是您更新的 fiddle :https://jsfiddle.net/86Lgaupt/

PS:我增加了 stroke-width 只是为了清楚地表明单击的矩形现在位于顶部。