Picking an optional maximum (Android)

Question

I'm looking for a way for a user to set a maximum (optional) number for creating an object via a form.

I was thinking of using a NumberPicker, but this requires that I set a top end right?

I was also thinking of using a Spinner, with options such as "< 5", "< 10", "< 25", "< 50" , ... "Unlimited," but wouldn't it be better to allow users to be more specific? (Somewhat important in my case)

So then I thought to use an EditText with a default text value of "Unlimited" and a hint that says "Set a maximum" ...

I apologize because I cannot provide details about what this is actually a maximum for due to legalities, but it would be best to allow the user to be as specific as possible, with no upper bound.

If you guys can think of a better way to do this or have any input please let me know - any help would be greatly appreciated!!

Answer 1

If you only have room for one object, then you could use interpret a string like "unlimited" or "Infinite". Make sure you check for all possible input possibilities though! Capitalizations, different words, the number 0 is often used. As you can see, this is messy.

A much safer and gradual option would be to have a toggle and a textbox (or other selector). This lets people choose limited/unlimited, and then optionally set a limit.

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Answer 2

It's difficult to give a complete answer without understanding the requirements, but there is a (potentially) existing pattern in stock Android - the data usage tab.

User selects the upper maximum by dragging the x-axis line up and down to set the maximum.

Downside is it may not give you the required precision to select the value - but you may be able to adapt the pattern for your use.