(#) Monochrome icon is not defined !!! WARNING: Monochrome icon is not defined This is a warning. Id : `MonochromeLauncherIcon` Summary : Monochrome icon is not defined Severity : Warning Category : Usability: Icons Platform : Android Vendor : Android Open Source Project Feedback : https://issuetracker.google.com/issues/new?component=192708 Since : 7.4.0 (January 2023) Affects : 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/MonochromeLauncherIconDetector.kt) 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/MonochromeLauncherIconDetectorTest.kt) If `android:roundIcon` and `android:icon` are both in your manifest, you must either remove the reference to `android:roundIcon` if it is not needed; or, supply the monochrome icon in the drawable defined by the `android:roundIcon` and `android:icon` attribute. For example, if `android:roundIcon` and `android:icon` are both in the manifest, a launcher might choose to use `android:roundIcon` over `android:icon` to display the adaptive app icon. Therefore, your themed application iconwill not show if your monochrome attribute is not also specified in `android:roundIcon`. (##) Example Here is an example of lint warnings produced by this check: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text res/drawable-ldpi/ic_icon.xml:2:Warning: The application adaptive icon is missing a monochrome tag [MonochromeLauncherIcon] <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"> ^ res/drawable-ldpi/ic_round_icon.xml:2:Warning: The application adaptive roundIcon is missing a monochrome tag [MonochromeLauncherIcon] <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here are the relevant source files: `res/drawable-ldpi/ic_icon.xml`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"> <background android:drawable="@drawable/ic_launcher_background" /> <foreground android:drawable="@drawable/ic_launcher_foreground" /> </adaptive-icon> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ `res/drawable-ldpi/ic_round_icon.xml`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"> <background android:drawable="@drawable/ic_launcher_background" /> <foreground android:drawable="@drawable/ic_launcher_foreground" /> </adaptive-icon> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ `src/AndroidManifest.xml`: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="test.pkg"> <application android:icon="@drawable/ic_icon" android:roundIcon="@drawable/ic_round_icon" android:label="@string/app_name" > </application> </manifest> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 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/MonochromeLauncherIconDetectorTest.kt) for the unit tests for this check to see additional scenarios. (##) Suppressing You can suppress false positives using one of the following mechanisms: * Adding the suppression attribute `tools:ignore="MonochromeLauncherIcon"` 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"`. ```xml <?xml version="1.0" encoding="UTF-8"?> <adaptive-icon xmlns:tools="http://schemas.android.com/tools" tools:ignore="MonochromeLauncherIcon" ...> ... </adaptive-icon> ``` * 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="MonochromeLauncherIcon" 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 'MonochromeLauncherIcon' } ``` In Android projects this should be nested inside an `android { }` block. * For manual invocations of `lint`, using the `--ignore` flag: ``` $ lint --ignore MonochromeLauncherIcon ...` ``` * Last, but not least, using baselines, as discussed [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).