Subpanel layout controller to hide empty subpanels

subpanels.js

({
	/* Author: Angel Magaña -- [email protected]
	*  File: ./custom/clients/base/layouts/subpanels/subpanels.js
	*	
	*  Extended subpanels layout controller for hiding
	*  subpanels without data upon parent record load (Sugar 7.2+)
	*  
	*  This customization applies to all modules 
	*/

    	extendsFrom: 'SubpanelsLayout',

    	showSubpanel: function(linkName) {

        	this._super('showSubpanel', [linkName]);
        
        	var currentModel = app.controller.context.get('model');

		/* currentModel.module returns the current parent module name
		*  which in turn could be used to selectively apply customization 
		*  to specific modules only, rather than system wide 
		*/

		/* Begin logic to check subpanel data and hide accordingly */ 
        	_.each(this._components, function(component) {
        
    		//Get link name (relationship) and load related records
            	var link = component.context.get('link');
            	var linkedData = currentModel.getRelatedCollection(link); 
        	var linkLength = -1;

			//Check how many related records were loaded for each link
			linkedData.once('reset', function(collection){
				linkLength = collection.length;
				
				//Hide subpanels without any data
				if (linkLength === 0)
				{
					component.remove();
				}
			});
            
        	});
	},
    
	_dispose: function(){
		this._super('_dispose');
	},
})

Thanks for your post, you saved my day. :)

Using getRelatedCollection() I was able to trigger when the last Subpanel is loaded, kind of onReady for Subpanels Rest API requests, counting collections.

Example:
https://gist.github.com/maranemil/c088fbfe57ccbb2c33ea