(#) Padding and margin symmetry !!! WARNING: Padding and margin symmetry This is a warning. Id : `RtlSymmetry` Summary : Padding and margin symmetry 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 If you specify padding or margin on the left side of a layout, you should probably also specify padding on the right side (and vice versa) for right-to-left layout symmetry. (##) Example Here is an example of lint warnings produced by this check: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text res/layout/relative.xml:29:Warning: When you define paddingRight you should probably also define paddingLeft for right-to-left symmetry [RtlSymmetry] android:paddingRight="120dip" -------------------- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here is the source file referenced above: `res/layout/relative.xml`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content" > <ProgressBar android:id="@+id/loading_progress" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:layout_marginBottom="60dip" android:layout_marginLeft="40dip" android:layout_marginTop="40dip" android:max="10000" /> <TextView android:id="@+id/text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentTop="true" android:layout_alignWithParentIfMissing="true" android:layout_marginBottom="60dip" android:layout_marginLeft="40dip" android:layout_marginTop="40dip" android:layout_toRightOf="@id/loading_progress" android:ellipsize="end" android:maxLines="3" android:paddingRight="120dip" android:text="@string/creating_instant_mix" android:textAppearance="?android:attr/textAppearanceMedium" /> <Button android:id="@+id/cancel" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignRight="@id/text" android:layout_below="@id/text" android:background="@null" android:text="@string/cancel" /> <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_above="@id/cancel" android:layout_alignLeft="@id/cancel" android:layout_alignRight="@id/cancel" android:scaleType="fitXY" android:src="@drawable/menu_list_divider" /> <Button android:id="@+id/cancel2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentStart="true" android:layout_alignEnd="@id/text" android:layout_below="@id/text" android:background="@null" android:layout_marginLeft="40dip" android:layout_marginRight="40dip" android:paddingLeft="120dip" android:paddingRight="120dip" android:text="@string/cancel" /> </RelativeLayout> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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.testSymmetry`. 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="RtlSymmetry"` 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("RtlSymmetry") fun method() { problematicStatement() } ``` or ```java // Java @SuppressWarnings("RtlSymmetry") void method() { problematicStatement(); } ``` * Using a suppression comment like this on the line above: ```kt //noinspection RtlSymmetry 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="RtlSymmetry" 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 'RtlSymmetry' } ``` In Android projects this should be nested inside an `android { }` block. * For manual invocations of `lint`, using the `--ignore` flag: ``` $ lint --ignore RtlSymmetry ...` ``` * Last, but not least, using baselines, as discussed [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).