javascript - 将节点移动到某个位置而不拖动

Question

我使用 D3.js，我希望在单击按钮后节点移动到某个位置(1; 1000)。

onclick 函数如下所示:

var node = svg.append("g")
          .attr("class", "nodes")
          .selectAll("circle")
          .data(nodes)
          .enter().append("circle")
           .attr("r", 8)
         .attr("fill", (d, i) => colours[i % 2])
            .style("stroke", "#000") 

     button.on("click", function(d) {
            nodes[1].x = 1;
            nodes[1].y = 1000;
            nodes[1].px = 1;
            nodes[1].py = 1000;
            nodes[1].fixed = true; };

我的问题是这不能正常工作。有人可以帮助我吗？

非常感谢!

Answer 1

您必须重新加热模拟。在 v4 中:

simulation.alpha(0.8).restart();
//value here------^
//between 0 and 1

这是一个演示，点击按钮将第一个节点的位置设置为左上角(同样，我使用的是v4):

var width = 400;
var height = 300;

var svg = d3.select("body")
  .append("svg")
  .attr("width", width)
  .attr("height", height);

var nodes = [{
  name: "foo",
  color: "blue"
}, {
  name: "bar",
  color: "green"
}, {
  name: "baz",
  color: "red"
}, {
  name: "foofoo",
  color: "yellow"
}, {
  name: "foobar",
  color: "blue"
}, {
  name: "foobaz",
  color: "green"
}, {
  name: "barfoo",
  color: "red"
}, {
  name: "barbar",
  color: "yellow"
}, {
  name: "barbaz",
  color: "blue"
}];

var links = [{
  "source": 0,
  "target": 1
}, {
  "source": 0,
  "target": 2
}, {
  "source": 0,
  "target": 3
}, {
  "source": 1,
  "target": 3
}, {
  "source": 1,
  "target": 4
}, {
  "source": 2,
  "target": 5
}, {
  "source": 3,
  "target": 6
}, {
  "source": 1,
  "target": 7
}, {
  "source": 6,
  "target": 8
}, {
  "source": 0,
  "target": 7
}, {
  "source": 2,
  "target": 6
}, {
  "source": 3,
  "target": 8
}];

var simulation = d3.forceSimulation()
  .force("link", d3.forceLink())
  .force("charge", d3.forceManyBody().strength(-50))
  .force("center", d3.forceCenter(width / 2, height / 2))
  .force("collide", d3.forceCollide(function(d) {
    return d.r + 1;
  }));

var link = svg.selectAll(null)
  .data(links)
  .enter()
  .append("line")
  .style("stroke", "#ccc")
  .style("stroke-width", 1);

var node = svg.selectAll(null)
  .data(nodes)
  .enter()
  .append("circle")
  .attr("r", function(d) {
    return d.r = 10;
  })
  .attr("stroke", "gray")
  .attr("stroke-width", "2px")
  .attr("fill", function(d) {
    return d.color
  })
  .call(d3.drag()
    .on("start", dragstarted)
    .on("drag", dragged)
    .on("end", dragended));;

var text = svg.selectAll(null)
  .data(nodes)
  .enter()
  .append("text")
  .attr("pointer-events", "none")
  .style("fill", "black")
  .attr("dy", "-1em")
  .attr("dx", "-1em")
  .text(function(d) {
    return d.name;
  });

simulation.nodes(nodes);
simulation.force("link")
  .links(links);

simulation.on("tick", function() {

  link.attr("x1", function(d) {
      return d.source.x;
    })
    .attr("y1", function(d) {
      return d.source.y;
    })
    .attr("x2", function(d) {
      return d.target.x;
    })
    .attr("y2", function(d) {
      return d.target.y;
    })

  node.attr("cx", function(d) {
    return d.x
  }).attr("cy", function(d) {
    return d.y
  });

  text.attr("x", function(d) {
    return d.x
  }).attr("y", function(d) {
    return d.y
  });

});

function dragstarted(d) {
  if (!d3.event.active) simulation.alphaTarget(0.3).restart();
  d.fx = d.x;
  d.fy = d.y;
}

function dragged(d) {
  d.fx = d3.event.x;
  d.fy = d3.event.y;
}

function dragended(d) {
  if (!d3.event.active) simulation.alphaTarget(0);
  d.fx = null;
  d.fy = null;
}

d3.select("button").on("click", function(d) {
  nodes[1].fx = 20;
  nodes[1].fy = 30;
  simulation.alpha(0.8).restart();
})

<script src="https://d3js.org/d3.v4.js"></script>
<button>Click me</button>
<br>