Android Accessibility: Using the Accessibility Scanner Tool in Kotlin XML Development

Creating inclusive applications is a fundamental aspect of modern Android development. Ensuring your app is accessible to all users, including those with disabilities, not only broadens your audience but also aligns with ethical development practices. Google provides an invaluable tool for this purpose: the Accessibility Scanner. In this blog post, we’ll delve into how to use the Accessibility Scanner effectively in your Kotlin XML-based Android projects to identify and rectify accessibility issues.

What is the Accessibility Scanner Tool?

The Accessibility Scanner is an Android tool designed to identify accessibility issues in your applications. It scans your app and provides recommendations for improving accessibility, such as suggesting content descriptions for images, increasing touch target sizes, and improving color contrast. By using the Accessibility Scanner, developers can proactively ensure that their apps are usable by people with a wide range of needs and abilities.

Why Use the Accessibility Scanner?

• Identify Accessibility Issues: Pinpoint specific areas in your app that need improvement for accessibility.
• Improve User Experience: Enhance the experience for all users, including those with disabilities.
• Comply with Accessibility Standards: Adhere to guidelines such as WCAG (Web Content Accessibility Guidelines).
• Automated Testing: Facilitates regular and automated accessibility testing during the development cycle.

How to Integrate and Use the Accessibility Scanner in Your Kotlin XML Project

To effectively use the Accessibility Scanner, follow these steps:

Step 1: Install the Accessibility Scanner App

First, download and install the Accessibility Scanner app from the Google Play Store:

• Accessibility Scanner on Google Play Store

Step 2: Enable the Accessibility Scanner

After installing the app, enable it in your device’s settings:

1. Go to your device’s Settings.
2. Navigate to Accessibility.
3. Find and enable the Accessibility Scanner service. You may need to grant permissions to allow it to overlay on other apps.

Step 3: Using the Accessibility Scanner with Your App

Now, let’s use the Accessibility Scanner with your Kotlin XML project:

1. Open your app on your Android device or emulator.
2. Start the Accessibility Scanner by tapping its icon, which usually appears as an overlay button.
3. Tap the “Scan” button to analyze the current screen of your app.

Step 4: Interpreting the Scan Results

The Accessibility Scanner will highlight potential issues on the screen and provide suggestions. Issues are categorized by severity and type.

• Missing Content Descriptions: Identifies images or icons without descriptive text for screen readers.
• Small Touch Targets: Highlights UI elements that are too small to be easily tapped.
• Low Contrast: Flags areas where the color contrast between text and background is insufficient.
• Redundant Text: Detects repeated or unnecessary text that can clutter the screen for screen reader users.

Example Scenario

Suppose the Accessibility Scanner flags an ImageView in your layout with a missing content description.

XML Layout (activity_main.xml)

<ImageView
    android:id="@+id/logoImageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/logo" />

Issue Identified

The Accessibility Scanner reports: “Missing `contentDescription` attribute”

Solution

Add the contentDescription attribute to provide a text description for screen readers:

<ImageView
    android:id="@+id/logoImageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/logo"
    android:contentDescription="@string/logo_description" />

Ensure you define the string resource in your strings.xml file:

strings.xml

<resources>
    <string name="logo_description">Company Logo</string>
</resources>

Step 5: Remediating Accessibility Issues in Kotlin Code

Sometimes, issues need to be addressed in your Kotlin code. For example, dynamically updating content descriptions:

Kotlin Code (MainActivity.kt)

import android.os.Bundle
import android.widget.ImageView
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val logoImageView: ImageView = findViewById(R.id.logoImageView)
        // Dynamically set content description
        logoImageView.contentDescription = "Updated Company Logo"
    }
}

Step 6: Iterative Testing

Accessibility improvements should be an iterative process:

1. Run the Accessibility Scanner.
2. Identify and fix the reported issues.
3. Re-scan your app to ensure the fixes are effective and that new issues haven’t been introduced.

Best Practices for Using the Accessibility Scanner

• Regular Scanning: Incorporate accessibility scanning into your regular development workflow.
• Detailed Descriptions: Provide meaningful and descriptive contentDescription attributes.
• Sufficient Contrast: Ensure sufficient color contrast ratios, especially for text.
• Appropriate Touch Target Sizes: Ensure interactive elements are large enough to be easily tapped.
• Test with Screen Readers: Use screen readers like TalkBack to experience your app as a visually impaired user would.

Advanced Tips

• Automated Accessibility Tests: Integrate automated accessibility tests into your CI/CD pipeline using tools like Espresso and the Accessibility Scanner.
• Custom Accessibility Actions: Implement custom accessibility actions for complex UI components to provide more granular control for screen reader users.

Conclusion

The Accessibility Scanner is an essential tool for every Android developer. By proactively using it in your Kotlin XML development process, you can ensure your apps are inclusive and usable by everyone. Regular accessibility testing, along with iterative improvements, not only enhances the user experience but also reflects responsible and ethical software development practices. Embrace accessibility testing as a core part of your workflow to build better apps for all users.