Xamarin.Forms App Icons, Splash Screens, and Permissions: A Detailed Guide for Beginners

Developing a Xamarin.Forms application for multiple platforms (iOS, Android, and UWP) requires not just coding but also attention to details such as app icons, splash screens, and permissions. Each detail contributes to a smooth user experience and proper functionality. In this guide, we will walk through the process of setting up app icons, splash screens, and handling permissions in Xamarin.Forms, catering to beginners.

Setting Up App Icons

Step 1: Create Icon Assets

• Icon Design: The app icon is the visual representation of your application. Ensure that your icon is simple, visually appealing, and recognizable at various sizes (e.g., 1024x1024 for iOS and different pixel densities for Android).
• Image File Formats: Use .png for Android and .png or .jpg for iOS. Ensure there is no transparent background on the iOS icon.
• Resolution Requirements:

  • iOS: Multiple resolutions are required for different devices (e.g., 29x29, 40x40, 50x50, 57x57, 60x60, 72x72, 76x76, 100x100, 114x114, 120x120, 144x144, 152x152, 167x167, 180x180, 1024x1024).

    • Android: Multiple sizes are needed, including ldpi (36x36), mdpi (48x48), hdpi (72x72), xhdpi (96x96), xxhdpi (144x144), and xxxhdpi (192x192).

  • UWP: The recommended size for square app icons is 512x512 or 50x50 for badges with a 256x256 scale.

Step 2: Place Icon Assets in Project Structure

• iOS:
  • Create an Assets.xcassets catalog in the iOS project.
  • Right-click on the Assets.xcassets directory and select "New Image Set" to add an icon.
  • Provide different sizes as required.
• Android:
  • Create folders in the Resources/drawable directory with appropriate names (e.g., drawable, drawable-hdpi, drawable-xhdpi, drawable-xxhdpi, drawable-xxxhdpi).
  • Place corresponding icons in each folder.
• UWP:
  • Place the icon in the Assets folder or the root of the project.
  • Reference the icon in the Package.appxmanifest file.

Step 3: Reference Icons in Platform-Specific Manifests

• iOS:
  • Open Info.plist and enter the icon names under the "Icons" section.
• Android:
  • Update the Application tag in AndroidManifest.xml with the android:icon attribute, pointing to the icon resource.
• UWP:
  • Modify the VisualElements section in Package.appxmanifest to point to the icon file.

Adding Splash Screens

Step 1: Create Splash Screen Assets

• Image Design: The splash screen should include the app logo and can have a consistent color scheme or background. Ensure it is legible and does not contain too many elements.
• File Formats: Use .png for simplicity and consistency.
• Resolution: Ensure the splash screen is appropriately sized for each device screen.

Step 2: Place Splash Screen Assets in Project Structure

• iOS:
  • Create a storyboarding or launch image set within Assets.xcassets.
• Android:
  • Create a drawable named splash_screen.xml with an <layer-list> that contains the background color and the logo.
  • Place the logo in the appropriate drawable directories.
• UWP:
  • Place the splash screen image in the Assets folder.
  • The image should be named SplashScreen.png.

Step 3: Reference Splash Screens in Platform-Specific Manifests

• iOS:
  • In Info.plist, set the appropriate launch images for different screen sizes.
• Android:
  • In MainActivity.cs, load the splash screen layout before the main activity.
  • Remove the splash screen layout after the main activity loads.
• UWP:
  • In Package.appxmanifest, update the VisualElements section to point to the splash screen image.

Requesting Permissions

Step 1: Define Required Permissions in Manifests

• iOS:
  • Add keys in Info.plist for permissions (e.g., access to camera, location, contacts).
• Android:
  • Add <uses-permission> tags in AndroidManifest.xml (e.g., android.permission.CAMERA).
  • For runtime permissions (API level 23 and above), request permissions programmatically.
• UWP:
  • Add <uap:Capability> tags in Package.appxmanifest (e.g., internetClientServer).

Step 2: Programmatically Request Permissions When Needed (For Android)

• Use the Permissions library to request permissions at runtime.
• Ensure that the user grants the required permissions before continuing with the functionality.

  // Example for camera permissions
  var status = await Permissions.RequestAsync<Permissions.Camera>();
  if (status == PermissionStatus.Granted)
  {
      // Camera permission granted
  }
  else
  {
      // Camera permission denied
  }
  

Step 3: Handle Permissions in Code-Behind

• Implement logic to proceed with functionality only if permissions are granted.
• Provide feedback to the user if permissions are denied, including guidance on how to enable them in the app settings.

Summary

Setting up app icons, splash screens, and permissions requires attention to detail and adherence to platform-specific guidelines. Here’s a quick recap:

1. Icons:

   • Design icons for all required resolutions.
   • Place icons in the correct directories per platform.
   • Update platform-specific manifests to reference icons.

2. Splash Screens:

   • Design splash screens for all required resolutions.
   • Place splash screen assets in the correct directories per platform.
   • Reference splash screens in platform-specific manifests.

3. Permissions:

   • List all necessary permissions in platform-specific manifests.
   • For Android, request permissions programmatically at runtime.
   • Handle permissions in code-behind to ensure smooth functionality.

By following these steps, you can ensure that your Xamarin.Forms application presents a professional image and functions smoothly on all targeted platforms. Happy coding!