Adding a value to Dialog API Field

Hi,

I am in need of showing the user a popup to gather more information before proceeding with a client side code. For this I am using [Dialog API](https://Dialog API)

For this I have implemented the following example:

frappe.prompt({
    label: 'Quantity',
    fieldname: 'quantity',
    fieldtype: 'Int'
}, (values) => {
    console.log(values.date);
})

Is there any way I can add predetermine the value of the field. In my case, I am requiring user to add the quantity to produce. And I will have a code that goes through, checks the total number of quantities required minus those that have already been allocated. So I would like to show only the remaining balance required. And the user has the option, to erase the balance required and make less quantities because that’s what they can process in that time frame. Hence, the requirement to show a prompt before going ahead.

Is there any way to do this currently with Dialog API?