Error:(49, 39) Fraction types not allowed (at 'layout_width' with value '50%')

Question

I'm trying to set the widht on 50% on an androiyd layout file this way

 android:layout_width="50%"

but I get this error

Error:(49, 39) Fraction types not allowed (at 'layout_width' with value '50%').

How I have to set the width on 50%?

Answer 1

Are you using Percentage layout? If so try this

 app:layout_widthPercent = "50%"

Answer 2

You need to use a library for this, since Android does not supply this by default. You might either need a or a PercentRelativeLayout or a PercentFrameLayout depending on your root layout.

Check this thread below:

How to use Percentage for android layout?

Edit, thanks to @Eugene

This was deprecated in Android 8.0 and up, you can use a ConstraintLayout as well, as described here.

https://developer.android.com/reference/android/support/percent/PercentFrameLayout.html

Answer 3

Recently you were able to do it with PercentFrameLayout and PercentRelativeLayout, but since they were deprecated in 26.0.0 the convenient way to set percentage value to your layout_width is to use guidelines which were introduced in ConstraintLayout

Here's my answer on another question on how to set percentage value https://stackoverflow.com/a/45865283/7158449