How do you achieve a keyboard that only allows num...

# compose

[S.]

How do you achieve a keyboard that only allows numeric input? no dots, dashes, only 0-9
KeyboardType.Number still allows special characters while android:inputType="number" doesn't

[S.]

also how much can you rely on this input restriction? what possibilities does the user have to bypass it

[Robert Menke]

I don’t think there is a way I just filter out the special characters

[S.]

yeah I generally use something like this in the textfield

onValueChange = {
                input = it
                inputError = input.toIntOrNull() == null
            }

and enabled = !inputError on the button

[Robert Menke]

Ha didn’t know about toIntOrNull I was manually replacing the characters 😅

[Adrijan Rogan]

I'm using NumberPassword

[Adrijan Rogan]

input.toIntOrNull() will fail on larger numbers and remove leading zeroes. Instead, use input.filter { it.isDigit() } to allow all unicode number decimal digits. You can also allow only "standard" ASCII digits.

[S.]

Depends on your use case. It fails with numbers larger than an int afaik so it does this check for you. If you need something bigger use toLontOrInt . Leading zeros are irrelevant for actual numbers anyways. If you want to work with phone numbers etc the filter option is the better choice ofc

[Adrijan Rogan]

I'm using it for a numeric password field, so I want a string as the result, not an integer. I agree there are valid use cases for toIntOrNull though