1

I am using subclassing to add custom properties to standard fabric objects like so: 

var IdRect: any = fabric.util.createClass(fabric.Rect, {
type: 'idRect',

initialize: function(id, dbType, options) {
    this.callSuper('initialize', options);
    this.id = id;
    this.dbType = dbType;
},

toObject: function () {
    return fabric.util.object.extend(this.callSuper('toObject'), {

    });
},

_render: function (ctx) {
    this.callSuper('_render', ctx);
}
});
IdRect.fromObject = function(options, callback) {
    var idRect =  new IdRect(null, null, options);
    callback && callback(idRect);
    return idRect;
}

One problem that I run into when trying to clone a selection of those custom objects is that fabric.util.getKlass returns null (Cannot read property 'fromObject' of undefined). Cloning them individually works fine.

Cybrooke
  • 31
  • 6

1 Answers1

1

Turns out you need to assign the property to the fabric library like so 

 fabric.IdRect = fabric.util.createClass(...)

or for typescript first assign fabric to a variable of type any to bypass the type system:

 var Fabric: any = fabric; 
 Fabric.IdRect = fabric.util.createClass(...)
Cybrooke
  • 31
  • 6