joint.all.js
function(evt, x, y) {

        if ( // target is a valid magnet start linking
            evt.target.getAttribute('magnet') &&
            this.paper.options.validateMagnet.call(this.paper, this, evt.target)
        ) {
                this.model.trigger('batch:start');

                var link = this.paper.getDefaultLink(this, evt.target);
                link.set({
                    source: {
                        id: this.model.id,
                        selector: this.getSelector(evt.target),
                        port: $(evt.target).attr('port')
                    },
                    target: { x: x, y: y }
                });

                this.paper.model.addCell(link);

	        this._linkView = this.paper.findViewByModel(link);
                this._linkView.startArrowheadMove('target');

        } else {

            this._dx = x;
            this._dy = y;

            joint.dia.CellView.prototype.pointerdown.apply(this, arguments);
        }
    }
function(evt, x, y) {

        if ( // target is a valid magnet start linking
            evt.target.getAttribute('magnet') &&
            this.paper.options.validateMagnet.call(this.paper, this, evt.target)
        ) {
                this.model.trigger('batch:start');

                var link = this.paper.getDefaultLink(this, evt.target);
                link.set({
                    source: {
                        id: this.model.id,
                        selector: this.getSelector(evt.target),
                        port: $(evt.target).attr('port')
                    },
                    target: { x: x, y: y }
                });

                this.paper.model.addCell(link);

	        this._linkView = this.paper.findViewByModel(link);
                this._linkView.startArrowheadMove('target');

        } else {

            this._dx = x;
            this._dy = y;

            joint.dia.CellView.prototype.pointerdown.apply(this, arguments);
        }
    }
function ( evt , x , y ) { if ( // target is a valid magnet start linking evt . target . getAttribute ( 'magnet' ) && this . paper . options . validateMagnet . call ( this . paper , this , evt . target ) ) { this . model . trigger ( 'batch:start' ) ; var link = this . paper . getDefaultLink ( this , evt . target ) ; link . set ( { source : { id : this . model . id , selector : this . getSelector ( evt . target ) , port : $ ( evt . target ) . attr ( 'port' ) } , target : { x : x , y : y } } ) ; this . paper . model . addCell ( link ) ; this . _linkView = this . paper . findViewByModel ( link ) ; this . _linkView . startArrowheadMove ( 'target' ) ; } else { this . _dx = x ; this . _dy = y ; joint . dia . CellView . prototype . pointerdown . apply ( this , arguments ) ; } }
Interaction. The controller part. ---------------------------------
Interaction . The controller part . ---------------------------------