JointJS：创建时需要目标元素 link

Question

我试图避免 links 以 space 结束，我只想允许 links 将一个元素与另一个元素连接起来。我当前的代码是：

new joint.shapes.basic.Rect({
  id: id,
  size: {
    width: width,
    height: height
  },
  attrs: {
    text: {
      text: label,
      'font-size': letterSize
    },
    rect: {
      width: width,
      height: height,
      rx: 5,
      ry: 5,
      stroke: '#555',
      'magnet': true
    }
  }
});

对于论文：

var paper = new joint.dia.Paper({
  el: $('#paper-basic'),
  width: 1250,
  height: 1000,
  model: graph,
  gridSize: 1,
  validateConnection: function(cellViewS, magnetS, cellViewT, magnetT, end, linkView) {
    // Prevent linking from output ports to input ports within one element.
    if (cellViewS === cellViewT) return false;
    // Prevent linking to input ports.
    return magnetT;
  },
  markAvailable: true
});

如何要求每个 link 都有一个源和一个目标？也许通过扩展 validateConnection?

Answer 1

Validate Connection 只会帮助验证磁铁，当 link 的末尾随机 space 在纸上时，它不会被调用。您可以使用以下方法删除不完整的 links：

// keep links from being incomplete
function isLinkInvalid(link){
    return (!link.prop('source/id') || !link.prop('target/id'));
}

paper.on('cell:pointerup', function(cellView) {
    if (! (cellView.model instanceof joint.dia.Link) ) return; // if it's not a link, don't worry about it
    // otherwise, add an event listener to it.  
    cellView.model.on('batch:stop', function(){
        var links = graph.getLinks();
        links.forEach(function(link){
            if(isLinkInvalid(link)){
                link.remove();
        }});
    });
});

它向 link 添加了一个 eventListener。在 'cell:pointerup' 上执行此操作很重要，因为在创建 link 时会调用 'batch:stop'。如果 link 没有目标 ID，则它没有连接到端口。

Answer 2

如果这仍然相关，现在 Paper 元素上有一个名为 linkPinning 的选项：

http://jointjs.com/api#dia.Paper.prototype.options

linkPinning - when set to true (the default), links can be pinned to the paper meaning a source or target of a link can be a point. If you do not want to let the user to drag a link and drop it somewhere in a blank paper area, set this to false. The effect is that the link will be returned to its original position whenever the user drops it somewhere in a blank paper area.

Answer 3

略different/shorter回答结合@Anora s和https://groups.google.com/forum/#!topic/jointjs/vwGWDFWVDJI

paper.on('cell:pointerup', function (cellView, evt) {
    var elem = cellView.model
    var source = elem.get('source')
    var target = elem.get('target')
    if (elem instanceof joint.dia.Link && (!source.id || !target.id)) {
        elem.remove()
    }
})

JointJS：创建时需要目标元素 link

JointJS: Require target element when creating link

jointjs