java.lang.IllegalArgumentException: Can only use lower 16 bits for requestCode

Question

I am writing an application where Activity A launches Activity B using

startActivityForResult(intent, -101);

but when called, it responded back with following error log:

E/AndroidRuntime( 1708): java.lang.IllegalArgumentException: Can only use lower 16 bits for requestCode
E/AndroidRuntime( 1708):    at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:837)

Probably it could be -101 but I am not sure. Does any one have any idea on this?

Alkahest

Change -101 to a positive number? – Weeping

Can only use lower 16 for requestCode : means request code should be >0 try startActivityForResult(intent, 101); – Octodecimo

Try this solution :https://mcmap.net/q/297753/-generate-16-bit-unique-ids-in-android-for-startactivityforresult – Heft

Answer 1

You need to pass a positive number to startActivityForResult.

Amylose

Although this is true, answers below are more specific. +1 – Wretch

Answer 2

You get this exception only in android.support.v4.app.FragmentActivity and not when you use android.app.Activity.

startActivityForResult() in FragmentActivity requires the requestCode to be of 16 bits, meaning the range is from 0 to 65535.

Also, validateRequestPermissionsRequestCode in FragmentActivity requires requestCode to be of 16 bits, meaning the range is from 0 to 65535.

For more info(if you want to see the source code) : https://mcmap.net/q/297754/-android-what-to-choose-for-requestcode-values

Falter

Answer 3

If you're using ActivityResult APIs, add this dependency to fix this issue:

implementation "androidx.fragment:fragment:1.3.4"

Bolo

Thank you! You should really put this into a self-answered question so other people can find it easily. – Phallicism

somehow and I really do not know why. but, You should add these two dependencies together. implementation 'androidx.activity:activity-ktx:x.x.x' implementation 'androidx.fragment:fragment-ktx:x.x.x' – Mazda

Why they told us how many dependencies required to have new features? Google docs sucks! Thanks by the way for helping. – Chiba

No idea why the error isn't more specific. At any rate, thank you. My hero <3 – Mg

Answer 4

It is also good to mention that this may happen if you use a number greater than 2^16 / 2 (which is 32768), so there's basically 2^15 options to not to screw this up.

Explanation: 16 bits can represent one of 65536 numbers, however, half of them are negative.

Henrietta

The limit is 65535 and not 32768. – Falter

@Falter Yes, negatif numbers are unused – Pellicle

Answer 5

For those who are using the new ActivityResult API,

If you are using the new way (ActivityResult) to open new Activity.

registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { 
    result ->
}

you have to use both of the below dependency

implementation 'androidx.activity:activity-ktx:1.2.0-rc01'
implementation 'androidx.fragment:fragment-ktx:1.3.0-rc02'

Rembert

It's kind of odd to use fragment implementation when not using it. But it works with it – Crisscross

I think stable version will solve the problem – Rembert

@Rembert i have to disappoint you.. they dont – Laoighis

This whole changes just messing things more and more. – Verner

Answer 6

You can only use lower 16 bits for requestCode means -- in binary terms -- you can use

0000000000000000 (16 bits) to 1111111111111111 (16 bits) [ binary ].

Or, equivalently

0 to 65535 [ base 10 ].

In decimal ("number") terms, this allows for 2^16 = 65536 combinations. Therefore, you can only use the numbers 0 all the way through 65535.

You also cannot use negative numbers.

Viquelia

Answer 7

The right answer is that you should use a 16 bits number for this purpose. The most safe solution for that is to always set your request code as short. If programmer attempts to write number more than 16 bits then the IDE won't let you to proceed because there will be an error.

Assume

Answer 8

Just add the two main dependencies for activityforresult API

for kotlin

implementation 'androidx.activity:activity-ktx:1.3.0-alpha03'
implementation 'androidx.fragment:fragment-ktx:1.3.0'

for java

implementation 'androidx.activity:activity:1.3.0-alpha03'
implementation 'androidx.fragment:fragment:1.3.0'

check here for the latest version.

Distant

Answer 9

Just add

for kotlin

implementation 'androidx.fragment:fragment-ktx:1.3.3'

Gnome