(#) Image without `contentDescription` !!! WARNING: Image without `contentDescription` This is a warning. Id : `ContentDescription` Summary : Image without `contentDescription` Severity : Warning Category : Accessibility Platform : Android Vendor : Android Open Source Project Feedback : https://issuetracker.google.com/issues/new?component=192708 Since : Initial Affects : Resource files Editing : This check runs on the fly in the IDE editor See : https://developer.android.com/guide/topics/ui/accessibility/apps#special-cases 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/AccessibilityDetector.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/AccessibilityDetectorTest.java) Copyright Year : 2011 Non-textual widgets like ImageViews and ImageButtons should use the `contentDescription` attribute to specify a textual description of the widget such that screen readers and other accessibility tools can adequately describe the user interface. Note that elements in application screens that are purely decorative and do not provide any content or enable a user action should not have accessibility content descriptions. In this case, set their descriptions to `@null`. If your app's minSdkVersion is 16 or higher, you can instead set these graphical elements' `android:importantForAccessibility` attributes to `no`. Note that for text fields, you should not set both the `hint` and the `contentDescription` attributes since the hint will never be shown. Just set the `hint`. !!! Tip This lint check has an associated quickfix available in the IDE. (##) Example Here is an example of lint warnings produced by this check: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text res/layout/accessibility.xml:4:Warning: Missing `contentDescription` attribute on image [ContentDescription] <ImageView android:id="@+id/android_logo" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/android_button" android:focusable="false" android:clickable="false" android:layout_weight="1.0" /> --------- res/layout/accessibility.xml:5:Warning: Missing `contentDescription` attribute on image [ContentDescription] <ImageButton android:importantForAccessibility="yes" android:id="@+id/android_logo2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/android_button" android:focusable="false" android:clickable="false" android:layout_weight="1.0" /> ----------- res/layout/accessibility.xml:9:Warning: Do not set both `contentDescription` and `hint`: the `contentDescription` will mask the `hint` [ContentDescription] <EditText android:hint="@string/label" android:id="@+android:id/summary" android:contentDescription="@string/label" /> ------------------------------------------ res/layout/accessibility.xml:12:Warning: Empty `contentDescription` attribute on image [ContentDescription] <ImageButton android:id="@+android:id/summary" android:contentDescription="TODO" /> --------------------------------- res/layout/accessibility.xml:13:Warning: Empty `contentDescription` attribute on image [ContentDescription] <ImageButton android:id="@+id/summary2" android:contentDescription="" /> ----------------------------- res/layout/accessibility.xml:14:Warning: Empty `contentDescription` attribute on image [ContentDescription] <ImageButton android:id="@+id/summary3" android:contentDescription="TODO" /> --------------------------------- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here is the source file referenced above: `res/layout/accessibility.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:id="@+id/newlinear" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:text="Button" android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <ImageView android:id="@+id/android_logo" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/android_button" android:focusable="false" android:clickable="false" android:layout_weight="1.0" /> <ImageButton android:importantForAccessibility="yes" android:id="@+id/android_logo2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/android_button" android:focusable="false" android:clickable="false" android:layout_weight="1.0" /> <Button android:text="Button" android:id="@+id/button2" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+android:id/summary" android:contentDescription="@string/label" /> <ImageButton android:importantForAccessibility="no" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/android_button" android:focusable="false" android:clickable="false" android:layout_weight="1.0" /> <EditText android:hint="@string/label" android:id="@+android:id/summary" android:contentDescription="@string/label" /> <EditText android:id="@+android:id/summary" android:contentDescription="@string/label" /> <EditText tools:ignore="ContentDescription" android:hint="@string/label" android:id="@+android:id/summary" android:contentDescription="@string/label" /> <ImageButton android:id="@+android:id/summary" android:contentDescription="TODO" /> <ImageButton android:id="@+id/summary2" android:contentDescription="" /> <ImageButton android:id="@+id/summary3" android:contentDescription="TODO" /> </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/AccessibilityDetectorTest.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, `AccessibilityDetector.testAccessibility`. 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="ContentDescription"` 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"?> <ImageButton xmlns:tools="http://schemas.android.com/tools" tools:ignore="ContentDescription" ...> ... </ImageButton> ``` * 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="ContentDescription" 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 'ContentDescription' } ``` In Android projects this should be nested inside an `android { }` block. * For manual invocations of `lint`, using the `--ignore` flag: ``` $ lint --ignore ContentDescription ...` ``` * Last, but not least, using baselines, as discussed [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).