android determine if device is in right to left language/layout

Question

Is there a way to determine if the device is in a right to left language (something like Arabic) as opposed to something that's left to right (English)?

Something compatible with older API levels (down to 10) is necessary

SOLUTION

i ended up using the xml method in the accepted answer. Farther down the line, i also added the code indicated here for instances where I didn't have access to getResources()

Identifying RTL language in Android

more info

This question still gets a lot of traffic; something else I wanted to point out: When I originally asked this I think it was partially to help address showing different pointing chevrons in RTL vs LTR -- another slick way of accomplishing this is by placing drawable resources in the standard and ldrtl directories -- means no code required to determine which one to show!

Dysuria

Answer 1

You could create a values-ldrtl folder with a xml file called isrighttoleft.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <bool name="is_right_to_left">true</bool>
</resources>

and in your values folder the same file with:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <bool name="is_right_to_left">false</bool>
</resources>

And finally in Code:

boolean isRightToLeft = getResources().getBoolean(R.bool.is_right_to_left);

The values-ldrtl will only be used on a device where the specific settings (e. g. Language) are right-to-left-read languages.

Cabezon

Thanks. I normally use this "technique" to determine wether the app is running on a tablet device or not ;) – Cabezon

I ended up using this over my solution because the above works all the time, my solution doesnt work inside onCreateView – Dysuria

Glad I could help you out ;) – Cabezon

Might want to add a "?>" to end of first line on those xml files, just for correct syntax. – Brest

Thanks. Just added them... ;) – Cabezon

You don't need extra resources for this. Check out my answer here : https://mcmap.net/q/377909/-android-determine-if-device-is-in-right-to-left-language-layout – Elonore

I added this line in my strings resource files. no need to create special file for it – Berner

The only working answer – Amphetamine

This will crash on old android devices. – Carrol

Answer 2

I think this is a better way:

val isLeftToRight = TextUtilsCompat.getLayoutDirectionFromLocale(Locale.getDefault()) == ViewCompat.LAYOUT_DIRECTION_LTR

Docs:

https://developer.android.com/reference/android/support/v4/text/TextUtilsCompat.html#getLayoutDirectionFromLocale(java.util.Locale)

Or, if you have minAPI 17 or above, you can just use this:

val isLeftToRight=TextUtils.getLayoutDirectionFromLocale(Locale.getDefault())==View.LAYOUT_DIRECTION_LTR

Docs:

https://developer.android.com/reference/android/text/TextUtils.html#getLayoutDirectionFromLocale(java.util.Locale)

Elonore

I just tested this in Android 10 with the device language set to Arabic, which my app is not translated into, and Locale.getDefault() returned en_US with LTR layout direction. Maybe this method gets the app's locale's layout direction instead of the device's? – Sequential

@Sequential In that case it's correct. If the app is in English, you want to treat it as LTR without respect to device's language. – Gullett

@Sequential Locale.getDefault() is supposed to return the current OS locale. Maybe you didn't set it right, or you didn't call the function again with the updated result of Locale.getDefault(). The code works with what it has. If it says it's English, it's LTR. – Elonore

Answer 3

Gr, a little bit longer googling and I would have found it before posting:

if (ViewCompat.getLayoutDirection(getView()) == ViewCompat.LAYOUT_DIRECTION_LTR) {
    // ...
}
else {
    // ...
}

http://developer.android.com/reference/android/support/v4/view/ViewCompat.html#getLayoutDirection(android.view.View)

Dysuria

You don't need a view to get it. Check out my answer here: https://mcmap.net/q/377909/-android-determine-if-device-is-in-right-to-left-language-layout – Elonore

Answer 4

If you are using Core KTX

you could use:

if (Locale.getDefault().layoutDirection == LayoutDirection.RTL)

Helicograph

if api 19 is fine – Precautionary

Ah layoutDirection seems to be an extension property? Didn't know those existed. It maps to TextUtils.getLayoutDirectionFromLocale() which is equivalent to the answer of @androiddeveloper. – Trilbi

Answer 5

Kotlin Code for detect app layout direction :

 val config = resources.configuration
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
        if (config.layoutDirection == View.LAYOUT_DIRECTION_LTR) {
           // showAlertMsg("LTR")
        } else {
           // showAlertMsg( "RTL")
        }
    }
    else {
        //TODO("VERSION.SDK_INT < JELLY_BEAN_MR1")
           }

Kaohsiung

Answer 6

If this is still getting considerable traffic, people should also consider Configuration.getLayoutDirection(), for API 17+. It will return either LayoutDirection.LTR or LayoutDirection.RTL. I imagine ViewCompat.getLayoutDirection(android.view.View) returns the direction that was actually used to layout a particular view. If you're doing something weird, such as trying to determine which person should be on which side of a chat screen (like me), this might be of use.

Effectually

There is a way for it to work on all API versions, without a view, here: https://mcmap.net/q/377909/-android-determine-if-device-is-in-right-to-left-language-layout – Elonore

I think it's good to use ViewCompat.getLayoutDirection(android.view.View) because it's common to hardcode direction of some views to not rotate in RTL languages or vice versa. – Incunabula

The poster asked the following: "Is there a way to determine if the device is in a right to left language". My answer is that there is a method in Configuration that does exactly this. These methods that have been suggested in View and ViewCompat, check only for a specific View, not the device. – Effectually

Answer 7

That's so easy. Just use: isRtll()

override fun isRtl(): Boolean {
    return super.isRtl()
}

Have a fun!

Loquitur

Answer 8

If your Build.VERSION.SDK_INT is bigger than JELLY_BEAN (16) you can use this:

val locale = Locale.getDefault() 
val isLtr = TextUtils.getLayoutDirectionFromLocale(locale) == ViewCompat.LAYOUT_DIRECTION_LTR

Clavicle

Answer 9

Yes,use the Bidi.getBaseLevel() function, it will return 0 for left-to-right and 1 for right to left.

http://developer.android.com/reference/java/text/Bidi.html#getBaseLevel()

Laurellaurella

I would have to have an instance of Bidi correct? In any case, I found a solution that seems to work. thanks though! – Dysuria

Yes, you have to istantiate one. – Laurellaurella

Please post the solution you found, for future reference. Thanks. – Laurellaurella

You don't have to create a new instance of anything. You can use this instead: https://mcmap.net/q/377909/-android-determine-if-device-is-in-right-to-left-language-layout – Elonore