As we already know which options and properties we wish to implement as a user option, defining the property panel for our drop-down list is fairly simple. We will utilize one expression component to help the user define their dimension, and two checkboxes to indicate whether to use one selected value and whether to apply read-only mode to the drop-down list. As we are not defining any calculations, we do not require any of the standard available properties, such as dimensions, measures, or add-ons. Keeping things simple, the property panel will look as follows:

//properties.js
define([], function(){ 
    return {
        type: "items", 
        component: "accordion", 
        items: { 
            settings: {
            label: "Settings",
            type: "items", 
            items: { 
                MasteringQSdrop-down: { 
                    type: "string", 
                    label: "drop-down Field", 
                    ref: "field", 
                    expression: "optional" 
                },
                includeFrequency: { 
                    label: "Include Frequency",
                    ref: "includeFrequency",
                    type: "boolean", 
                    defaultValue: false
                },
                ReadOnly: { 
                    label: "Read Only",
                    ref: "readonly",
                    type: "boolean", 
                    defaultValue: false
                }
            } 
            } 
        }
    };
});

This, in Qlik Sense, will look as follows: