(#) Using RTL attributes without enabling RTL support
!!! WARNING: Using RTL attributes without enabling RTL support
This is a warning.
Id
: `RtlEnabled`
Summary
: Using RTL attributes without enabling RTL support
Severity
: Warning
Category
: Internationalization: Bidirectional Text
Platform
: Android
Vendor
: Android Open Source Project
Feedback
: https://issuetracker.google.com/issues/new?component=192708
Since
: Initial
Affects
: Kotlin and Java files, manifest files and resource files
Editing
: This check runs on the fly in the IDE editor
Implementation
: [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/RtlDetector.java)
Tests
: [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/RtlDetectorTest.java)
Copyright Year
: 2017
To enable right-to-left support, when running on API 17 and higher, you
must set the `android:supportsRtl` attribute in the manifest
`` element.
If you have started adding RTL attributes, but have not yet finished the
migration, you can set the attribute to false to satisfy this lint
check.
(##) Example
Here is an example of lint warnings produced by this check:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text
AndroidManifest.xml:Warning: The project references RTL attributes, but
does not explicitly enable or disable RTL support with
android:supportsRtl in the manifest [RtlEnabled]
0 errors, 4 warnings
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Here are the relevant source files:
`AndroidManifest.xml`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="test.rtl">
<uses-sdk android:minSdkVersion="5" android:targetSdkVersion="17" />
</manifest>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
`res/layout/rtl.xml`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:ignore="HardcodedText" >
<!-- Warn: Use start instead of left -->
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left"
android:text="Button" />
<!-- Warn: Use end instead of right with layout_gravity -->
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Button" />
<!-- Warn: Use end instead of right with gravity -->
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="right"
android:text="TextView" />
<!-- OK: No warning -->
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="start"
android:text="Button" />
<!-- OK: No warning -->
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end"
android:text="Button" />
<!-- OK: No warning -->
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="end"
android:text="TextView" />
<!-- OK: Suppressed -->
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:text="Button"
tools:ignore="RtlHardcoded" />
</LinearLayout>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You can also visit the
[source code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/RtlDetectorTest.java)
for the unit tests for this check to see additional scenarios.
The above example was automatically extracted from the first unit test
found for this lint check, `RtlDetector.testTarget17WithRtl`.
To report a problem with this extracted sample, visit
https://issuetracker.google.com/issues/new?component=192708.
(##) Suppressing
You can suppress false positives using one of the following mechanisms:
* Adding the suppression attribute `tools:ignore="RtlEnabled"` on the
problematic XML element (or one of its enclosing elements). You may
also need to add the following namespace declaration on the root
element in the XML file if it's not already there:
`xmlns:tools="http://schemas.android.com/tools"`.
* Using a suppression annotation like this on the enclosing
element:
```kt
// Kotlin
@Suppress("RtlEnabled")
fun method() {
problematicStatement()
}
```
or
```java
// Java
@SuppressWarnings("RtlEnabled")
void method() {
problematicStatement();
}
```
* Using a suppression comment like this on the line above:
```kt
//noinspection RtlEnabled
problematicStatement()
```
* Using a special `lint.xml` file in the source tree which turns off
the check in that folder and any sub folder. A simple file might look
like this:
```xml
<?xml version="1.0" encoding="UTF-8"?>
<lint>
<issue id="RtlEnabled" severity="ignore" />
</lint>
```
Instead of `ignore` you can also change the severity here, for
example from `error` to `warning`. You can find additional
documentation on how to filter issues by path, regular expression and
so on
[here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html).
* In Gradle projects, using the DSL syntax to configure lint. For
example, you can use something like
```gradle
lintOptions {
disable 'RtlEnabled'
}
```
In Android projects this should be nested inside an `android { }`
block.
* For manual invocations of `lint`, using the `--ignore` flag:
```
$ lint --ignore RtlEnabled ...`
```
* Last, but not least, using baselines, as discussed
[here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).