Hi,

I am beginner in lightning.
Trying to implement DuelListBox and getting formatting issues with same.
Here is the code I am using:
DuelListComponent.cmp:

<aura:component implements="flexipage:availableForAllPageTypes">
    <aura:attribute name="listOptions" type="List" default="[]"/>
    <aura:attribute name="defaultOptions" type="List" default="[]"/>
    <aura:attribute name="requiredOptions" type="List" default="[]"/>
    <aura:handler name="init" value="{! this }" action="{! c.initialize }"/>
    <lightning:dualListbox aura:id="selectOptions" name="Select Options"  label= "Select Options"
                           sourceLabel="Available Options"
                           selectedLabel="Selected Options"
                           options="{! v.listOptions }"
                           value="{! v.defaultOptions }"
                           requiredOptions="{! v.requiredOptions }"
                           onchange="{! c.handleChange }"/>
</aura:component>

DuelListController.js​​​​​​​

/** Client-Side Controller **/
({
    initialize: function (component, event, helper) {
        var options = [
            { value: "1", label: "Option 1" },
            { value: "2", label: "Option 2" },
            { value: "3", label: "Option 3" },
            { value: "4", label: "Option 4" },
            { value: "5", label: "Option 5" },
            { value: "6", label: "Option 6" },
            { value: "7", label: "Option 7" },
            { value: "8", label: "Option 8" },
        ];
        var values = ["7", "2", "3"];
        var required = ["2", "7"];
        component.set("v.listOptions", options);
        component.set("v.defaultOptions", values);
        component.set("v.requiredOptions", required);
    },
    handleChange: function (cmp, event) {
        // Get the list of the "value" attribute on all the selected options
        var selectedOptionsList = event.getParam("value");
        alert("Options selected: '" + selectedOptionsList + "'");
    }
})

and here is the output I am getting:

Could you please help me with the same?

Regards,
Prasad