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robschmuecker/README.md

Last active January 31, 2024 18:30
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  1. robschmuecker revised this gist Jun 20, 2014. 1 changed file with 4 additions and 2 deletions.
    6 changes: 4 additions & 2 deletions README.md
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    Original file line number Diff line number Diff line change
    @@ -2,7 +2,7 @@ This is an example of a collapsible drag and drop tree implementing slightly mod

    This is posted in order to demonstrate a viable answer for a Stack Overflow question http://stackoverflow.com/questions/20539922/has-anyone-produced-a-virtualised-javascript-tree-for-thousands-of-nodes

    The only difference between this gist and the one refereced above is that the JSON file has changed. Each node contains 15 children and the depth is 4. Hence over 50,000 nodes.
    The only difference between this gist and the one referenced above is that the JSON file has changed. Each node contains 15 children and the depth is 4. Hence over 50,000 nodes.

    The performance is fine if not too many of the nodes are present at once in the DOM.
    The JSON was contructed at http://www.json-generator.com/ with the following markup
    @@ -41,4 +41,6 @@ The JSON was contructed at http://www.json-generator.com/ with the following mar
    }
    ]
    }
    ```
    ```

    For any help/queries, http://www.robschmuecker.com @robschmuecker or robert.schmuecker at gmail dot com
  2. robschmuecker revised this gist Dec 12, 2013. 1 changed file with 224196 additions and 0 deletions.
    224,196 changes: 224,196 additions & 0 deletions manyNodes.json
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    224,196 additions, 0 deletions not shown because the diff is too large. Please use a local Git client to view these changes.
  3. robschmuecker created this gist Dec 12, 2013.
    44 changes: 44 additions & 0 deletions README.md
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    @@ -0,0 +1,44 @@
    This is an example of a collapsible drag and drop tree implementing slightly modified code from https://gist.github.com/robschmuecker/7880033

    This is posted in order to demonstrate a viable answer for a Stack Overflow question http://stackoverflow.com/questions/20539922/has-anyone-produced-a-virtualised-javascript-tree-for-thousands-of-nodes

    The only difference between this gist and the one refereced above is that the JSON file has changed. Each node contains 15 children and the depth is 4. Hence over 50,000 nodes.

    The performance is fine if not too many of the nodes are present at once in the DOM.
    The JSON was contructed at http://www.json-generator.com/ with the following markup


    ```JSON
    {
    user_id: '{{index}}',
    name: '{{firstName}} {{surname}}',
    children: [
    '{{repeat(15)}}',
    {
    user_id: '{{index}}',
    name: '{{firstName}} {{surname}}',
    children: [
    '{{repeat(15)}}',
    {
    user_id: '{{index}}',
    name: '{{firstName}} {{surname}}',
    children: [
    '{{repeat(15)}}',
    {
    user_id: '{{index}}',
    name: '{{firstName}} {{surname}}',
    children: [
    '{{repeat(15)}}',
    {
    user_id: '{{index}}',
    name: '{{firstName}} {{surname}}'
    }
    ]
    }
    ]
    }
    ]
    }
    ]
    }
    ```
    527 changes: 527 additions & 0 deletions dndTree.js
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    Original file line number Diff line number Diff line change
    @@ -0,0 +1,527 @@
    // Get JSON data
    treeJSON = d3.json("manyNodes.json", function(error, treeData) {

    // Calculate total nodes, max label length
    var totalNodes = 0;
    var maxLabelLength = 0;
    // variables for drag/drop
    var selectedNode = null;
    var draggingNode = null;
    // panning variables
    var panSpeed = 200;
    var panBoundary = 20; // Within 20px from edges will pan when dragging.
    // Misc. variables
    var i = 0;
    var duration = 750;
    var root;

    // size of the diagram
    var viewerWidth = $(document).width();
    var viewerHeight = $(document).height();

    var tree = d3.layout.tree()
    .size([viewerHeight, viewerWidth]);

    // define a d3 diagonal projection for use by the node paths later on.
    var diagonal = d3.svg.diagonal()
    .projection(function(d) {
    return [d.y, d.x];
    });

    // A recursive helper function for performing some setup by walking through all nodes

    function visit(parent, visitFn, childrenFn) {
    if (!parent) return;

    visitFn(parent);

    var children = childrenFn(parent);
    if (children) {
    var count = children.length;
    for (var i = 0; i < count; i++) {
    visit(children[i], visitFn, childrenFn);
    }
    }
    }

    // Call visit function to establish maxLabelLength
    visit(treeData, function(d) {
    totalNodes++;
    maxLabelLength = Math.max(d.name.length, maxLabelLength);

    }, function(d) {
    return d.children && d.children.length > 0 ? d.children : null;
    });


    // sort the tree according to the node names

    function sortTree() {
    tree.sort(function(a, b) {
    return b.name.toLowerCase() < a.name.toLowerCase() ? 1 : -1;
    });
    }
    // Sort the tree initially incase the JSON isn't in a sorted order.
    sortTree();

    // TODO: Pan function, can be better implemented.

    function pan(domNode, direction) {
    var speed = panSpeed;
    if (panTimer) {
    clearTimeout(panTimer);
    translateCoords = d3.transform(svgGroup.attr("transform"));
    if (direction == 'left' || direction == 'right') {
    translateX = direction == 'left' ? translateCoords.translate[0] + speed : translateCoords.translate[0] - speed;
    translateY = translateCoords.translate[1];
    } else if (direction == 'up' || direction == 'down') {
    translateX = translateCoords.translate[0];
    translateY = direction == 'up' ? translateCoords.translate[1] + speed : translateCoords.translate[1] - speed;
    }
    scaleX = translateCoords.scale[0];
    scaleY = translateCoords.scale[1];
    scale = zoomListener.scale();
    svgGroup.transition().attr("transform", "translate(" + translateX + "," + translateY + ")scale(" + scale + ")");
    d3.select(domNode).select('g.node').attr("transform", "translate(" + translateX + "," + translateY + ")");
    zoomListener.scale(zoomListener.scale());
    zoomListener.translate([translateX, translateY]);
    panTimer = setTimeout(function() {
    pan(domNode, speed, direction);
    }, 50);
    }
    }

    // Define the zoom function for the zoomable tree

    function zoom() {
    svgGroup.attr("transform", "translate(" + d3.event.translate + ")scale(" + d3.event.scale + ")");
    }


    // define the zoomListener which calls the zoom function on the "zoom" event constrained within the scaleExtents
    var zoomListener = d3.behavior.zoom().scaleExtent([0.1, 3]).on("zoom", zoom);

    function initiateDrag(d, domNode) {
    draggingNode = d;
    d3.select(domNode).select('.ghostCircle').attr('pointer-events', 'none');
    d3.selectAll('.ghostCircle').attr('class', 'ghostCircle show');
    d3.select(domNode).attr('class', 'node activeDrag');

    svgGroup.selectAll("g.node").sort(function(a, b) { // select the parent and sort the path's
    if (a.id != draggingNode.id) return 1; // a is not the hovered element, send "a" to the back
    else return -1; // a is the hovered element, bring "a" to the front
    });
    // if nodes has children, remove the links and nodes
    if (nodes.length > 1) {
    // remove link paths
    links = tree.links(nodes);
    nodePaths = svgGroup.selectAll("path.link")
    .data(links, function(d) {
    return d.target.id;
    }).remove();
    // remove child nodes
    nodesExit = svgGroup.selectAll("g.node")
    .data(nodes, function(d) {
    return d.id;
    }).filter(function(d, i) {
    if (d.id == draggingNode.id) {
    return false;
    }
    return true;
    }).remove();
    }

    // remove parent link
    parentLink = tree.links(tree.nodes(draggingNode.parent));
    svgGroup.selectAll('path.link').filter(function(d, i) {
    if (d.target.id == draggingNode.id) {
    return true;
    }
    return false;
    }).remove();

    dragStarted = null;
    }

    // define the baseSvg, attaching a class for styling and the zoomListener
    var baseSvg = d3.select("#tree-container").append("svg")
    .attr("width", viewerWidth)
    .attr("height", viewerHeight)
    .attr("class", "overlay")
    .call(zoomListener);


    // Define the drag listeners for drag/drop behaviour of nodes.
    dragListener = d3.behavior.drag()
    .on("dragstart", function(d) {
    if (d == root) {
    return;
    }
    dragStarted = true;
    nodes = tree.nodes(d);
    d3.event.sourceEvent.stopPropagation();
    // it's important that we suppress the mouseover event on the node being dragged. Otherwise it will absorb the mouseover event and the underlying node will not detect it d3.select(this).attr('pointer-events', 'none');
    })
    .on("drag", function(d) {
    if (d == root) {
    return;
    }
    if (dragStarted) {
    domNode = this;
    initiateDrag(d, domNode);
    }

    // get coords of mouseEvent relative to svg container to allow for panning
    relCoords = d3.mouse($('svg').get(0));
    if (relCoords[0] < panBoundary) {
    panTimer = true;
    pan(this, 'left');
    } else if (relCoords[0] > ($('svg').width() - panBoundary)) {

    panTimer = true;
    pan(this, 'right');
    } else if (relCoords[1] < panBoundary) {
    panTimer = true;
    pan(this, 'up');
    } else if (relCoords[1] > ($('svg').height() - panBoundary)) {
    panTimer = true;
    pan(this, 'down');
    } else {
    try {
    clearTimeout(panTimer);
    } catch (e) {

    }
    }

    d.x0 += d3.event.dy;
    d.y0 += d3.event.dx;
    var node = d3.select(this);
    node.attr("transform", "translate(" + d.y0 + "," + d.x0 + ")");
    updateTempConnector();
    }).on("dragend", function(d) {
    if (d == root) {
    return;
    }
    domNode = this;
    if (selectedNode) {
    // now remove the element from the parent, and insert it into the new elements children
    var index = draggingNode.parent.children.indexOf(draggingNode);
    if (index > -1) {
    draggingNode.parent.children.splice(index, 1);
    }
    if (typeof selectedNode.children !== 'undefined' || typeof selectedNode._children !== 'undefined') {
    if (typeof selectedNode.children !== 'undefined') {
    selectedNode.children.push(draggingNode);
    } else {
    selectedNode._children.push(draggingNode);
    }
    } else {
    selectedNode.children = [];
    selectedNode.children.push(draggingNode);
    }
    // Make sure that the node being added to is expanded so user can see added node is correctly moved
    expand(selectedNode);
    sortTree();
    endDrag();
    } else {
    endDrag();
    }
    });

    function endDrag() {
    selectedNode = null;
    d3.selectAll('.ghostCircle').attr('class', 'ghostCircle');
    d3.select(domNode).attr('class', 'node');
    // now restore the mouseover event or we won't be able to drag a 2nd time
    d3.select(domNode).select('.ghostCircle').attr('pointer-events', '');
    updateTempConnector();
    if (draggingNode !== null) {
    update(root);
    centerNode(draggingNode);
    draggingNode = null;
    }
    }

    // Helper functions for collapsing and expanding nodes.

    function collapse(d) {
    if (d.children) {
    d._children = d.children;
    d._children.forEach(collapse);
    d.children = null;
    }
    }

    function expand(d) {
    if (d._children) {
    d.children = d._children;
    d.children.forEach(expand);
    d._children = null;
    }
    }

    var overCircle = function(d) {
    selectedNode = d;
    updateTempConnector();
    };
    var outCircle = function(d) {
    selectedNode = null;
    updateTempConnector();
    };

    // Function to update the temporary connector indicating dragging affiliation
    var updateTempConnector = function() {
    var data = [];
    if (draggingNode !== null && selectedNode !== null) {
    // have to flip the source coordinates since we did this for the existing connectors on the original tree
    data = [{
    source: {
    x: selectedNode.y0,
    y: selectedNode.x0
    },
    target: {
    x: draggingNode.y0,
    y: draggingNode.x0
    }
    }];
    }
    var link = svgGroup.selectAll(".templink").data(data);

    link.enter().append("path")
    .attr("class", "templink")
    .attr("d", d3.svg.diagonal())
    .attr('pointer-events', 'none');

    link.attr("d", d3.svg.diagonal());

    link.exit().remove();
    };

    // Function to center node when clicked/dropped so node doesn't get lost when collapsing/moving with large amount of children.

    function centerNode(source) {
    scale = zoomListener.scale();
    x = -source.y0;
    y = -source.x0;
    x = x * scale + viewerWidth / 2;
    y = y * scale + viewerHeight / 2;
    d3.select('g').transition()
    .duration(duration)
    .attr("transform", "translate(" + x + "," + y + ")scale(" + scale + ")");
    zoomListener.scale(scale);
    zoomListener.translate([x, y]);
    }

    // Toggle children function

    function toggleChildren(d) {
    if (d.children) {
    d._children = d.children;
    d.children = null;
    } else if (d._children) {
    d.children = d._children;
    d._children = null;
    }
    return d;
    }

    // Toggle children on click.

    function click(d) {
    if (d3.event.defaultPrevented) return; // click suppressed
    d = toggleChildren(d);
    update(d);
    centerNode(d);
    }

    function update(source) {
    // Compute the new height, function counts total children of root node and sets tree height accordingly.
    // This prevents the layout looking squashed when new nodes are made visible or looking sparse when nodes are removed
    // This makes the layout more consistent.
    var levelWidth = [1];
    var childCount = function(level, n) {

    if (n.children && n.children.length > 0) {
    if (levelWidth.length <= level + 1) levelWidth.push(0);

    levelWidth[level + 1] += n.children.length;
    n.children.forEach(function(d) {
    childCount(level + 1, d);
    });
    }
    };
    childCount(0, root);
    var newHeight = d3.max(levelWidth) * 25; // 25 pixels per line
    tree = tree.size([newHeight, viewerWidth]);

    // Compute the new tree layout.
    var nodes = tree.nodes(root).reverse(),
    links = tree.links(nodes);

    // Set widths between levels based on maxLabelLength.
    nodes.forEach(function(d) {
    d.y = (d.depth * (maxLabelLength * 10)); //maxLabelLength * 10px
    // alternatively to keep a fixed scale one can set a fixed depth per level
    // Normalize for fixed-depth by commenting out below line
    // d.y = (d.depth * 500); //500px per level.
    });

    // Update the nodes…
    node = svgGroup.selectAll("g.node")
    .data(nodes, function(d) {
    return d.id || (d.id = ++i);
    });

    // Enter any new nodes at the parent's previous position.
    var nodeEnter = node.enter().append("g")
    .call(dragListener)
    .attr("class", "node")
    .attr("transform", function(d) {
    return "translate(" + source.y0 + "," + source.x0 + ")";
    })
    .on('click', click);

    nodeEnter.append("circle")
    .attr('class', 'nodeCircle')
    .attr("r", 0)
    .style("fill", function(d) {
    return d._children ? "lightsteelblue" : "#fff";
    });

    nodeEnter.append("text")
    .attr("x", function(d) {
    return d.children || d._children ? -10 : 10;
    })
    .attr("dy", ".35em")
    .attr('class', 'nodeText')
    .attr("text-anchor", function(d) {
    return d.children || d._children ? "end" : "start";
    })
    .text(function(d) {
    return d.name;
    })
    .style("fill-opacity", 0);

    // phantom node to give us mouseover in a radius around it
    nodeEnter.append("circle")
    .attr('class', 'ghostCircle')
    .attr("r", 30)
    .attr("opacity", 0.2) // change this to zero to hide the target area
    .style("fill", "red")
    .attr('pointer-events', 'mouseover')
    .on("mouseover", function(node) {
    overCircle(node);
    })
    .on("mouseout", function(node) {
    outCircle(node);
    });

    // Update the text to reflect whether node has children or not.
    node.select('text')
    .attr("x", function(d) {
    return d.children || d._children ? -10 : 10;
    })
    .attr("text-anchor", function(d) {
    return d.children || d._children ? "end" : "start";
    })
    .text(function(d) {
    return d.name;
    });

    // Change the circle fill depending on whether it has children and is collapsed
    node.select("circle.nodeCircle")
    .attr("r", 4.5)
    .style("fill", function(d) {
    return d._children ? "lightsteelblue" : "#fff";
    });

    // Transition nodes to their new position.
    var nodeUpdate = node.transition()
    .duration(duration)
    .attr("transform", function(d) {
    return "translate(" + d.y + "," + d.x + ")";
    });

    // Fade the text in
    nodeUpdate.select("text")
    .style("fill-opacity", 1);

    // Transition exiting nodes to the parent's new position.
    var nodeExit = node.exit().transition()
    .duration(duration)
    .attr("transform", function(d) {
    return "translate(" + source.y + "," + source.x + ")";
    })
    .remove();

    nodeExit.select("circle")
    .attr("r", 0);

    nodeExit.select("text")
    .style("fill-opacity", 0);

    // Update the links…
    var link = svgGroup.selectAll("path.link")
    .data(links, function(d) {
    return d.target.id;
    });

    // Enter any new links at the parent's previous position.
    link.enter().insert("path", "g")
    .attr("class", "link")
    .attr("d", function(d) {
    var o = {
    x: source.x0,
    y: source.y0
    };
    return diagonal({
    source: o,
    target: o
    });
    });

    // Transition links to their new position.
    link.transition()
    .duration(duration)
    .attr("d", diagonal);

    // Transition exiting nodes to the parent's new position.
    link.exit().transition()
    .duration(duration)
    .attr("d", function(d) {
    var o = {
    x: source.x,
    y: source.y
    };
    return diagonal({
    source: o,
    target: o
    });
    })
    .remove();

    // Stash the old positions for transition.
    nodes.forEach(function(d) {
    d.x0 = d.x;
    d.y0 = d.y;
    });
    }

    // Append a group which holds all nodes and which the zoom Listener can act upon.
    var svgGroup = baseSvg.append("g");

    // Define the root
    root = treeData;
    root.x0 = viewerHeight / 2;
    root.y0 = 0;

    // Collapse all children of roots children before rendering.
    root.children.forEach(function(child){
    collapse(child);
    });

    // Layout the tree initially and center on the root node.
    update(root);
    centerNode(root);
    });
    51 changes: 51 additions & 0 deletions index.html
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    <!DOCTYPE html>
    <meta charset="utf-8">
    <style type="text/css">

    .node {
    cursor: pointer;
    }

    .overlay{
    background-color:#EEE;
    }

    .node circle {
    fill: #fff;
    stroke: steelblue;
    stroke-width: 1.5px;
    }

    .node text {
    font-size:10px;
    font-family:sans-serif;
    }

    .link {
    fill: none;
    stroke: #ccc;
    stroke-width: 1.5px;
    }

    .templink {
    fill: none;
    stroke: red;
    stroke-width: 3px;
    }

    .ghostCircle.show{
    display:block;
    }

    .ghostCircle, .activeDrag .ghostCircle{
    display: none;
    }

    </style>
    <script src="http://code.jquery.com/jquery-1.10.2.min.js"></script>
    <script src="http://d3js.org/d3.v3.min.js"></script>
    <script src="dndTree.js"></script>
    <body>
    <div id="tree-container"></div>
    </body>
    </html>