.NET MAUI

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Advanced & Enterprise Advanced Data Binding & Collections App Lifecycle & Windows Best Practices & Architecture Concurrency & Threading Controls & Views Data Binding & MVVM Dependency Injection & Services Desktop - WinUI & Mac Catalyst Device Features & Essentials Fonts, Icons & Media Forms, Input & Validation Fundamentals & Architecture Gestures & Animations Graphics & Drawing Local Storage & Data Maps & Location Migration from Xamarin.Forms Native Interop & Libraries Networking & APIs

.NET MAUI

Device Features & Essentials

Q: How do you get the device's geolocation in MAUI?

Use Geolocation.Default.GetLocationAsync (last-known or a fresh request with GeolocationRequest specifying accuracy and timeout). Request location permission first. GetLastKnownLocationAsync is faster but may be stale; GetLocationAsync forces a fix.

Q: How do you pick or capture a photo in MAUI?

Use MediaPicker.Default.PickPhotoAsync to choose from the gallery or CapturePhotoAsync to use the camera (camera requires permission and hardware). Both return a FileResult you can open as a stream to display or upload.

Q: How do you open the browser, dialer, or email from MAUI?

Use the launcher/communication APIs: Browser.Default.OpenAsync for URLs, PhoneDialer.Default.Open for phone numbers, Email.Default.ComposeAsync for email, and Sms/Map for others. These invoke the platform's default apps rather than embedding them.

Q: How do you read device sensors like the accelerometer?

Use the sensor APIs (Accelerometer, Gyroscope, Compass, Barometer). Subscribe to ReadingChanged and call Start with a SensorSpeed, then Stop when done to save battery. Marshal UI updates to the main thread.

Q: How do you get device and display information in MAUI?

Use DeviceInfo (model, manufacturer, platform, version, idiom, DeviceType—physical vs virtual) and DeviceDisplay (screen metrics, density, orientation, keep-screen-on). These help adapt UI and diagnose device-specific issues.

Q: How do you use the Clipboard and Share APIs?

Clipboard.Default.SetTextAsync/GetTextAsync copies and reads text. Share.Default.RequestAsync opens the OS share sheet with text or files (ShareTextRequest/ShareFileRequest), letting users send content to other apps.

Q: How do you run background work or scheduled tasks in MAUI?

MAUI has no unified background API; use platform mechanisms: Android WorkManager/foreground services, iOS BGTaskScheduler/background modes, and Windows background tasks—wrapped behind a shared interface. For short async work while active, normal tasks suffice; true background execution needs native scheduling per platform.

7 question(s)

How do you get the device's geolocation in MAUI?

Beginner

Use Geolocation.Default.GetLocationAsync (last-known or a fresh request with GeolocationRequest specifying accuracy and timeout). Request location permission first. GetLastKnownLocationAsync is faster but may be stale; GetLocationAsync forces a fix.

var request = new GeolocationRequest(GeolocationAccuracy.Medium,
    TimeSpan.FromSeconds(10));
var loc = await Geolocation.Default.GetLocationAsync(request);

Real-world example A weather app fetches the user's coordinates to show local conditions after requesting location permission.

Common follow-ups: Last-known vs fresh location? | What permission is required?

Geolocation Permissions Device Features & Essentials

How do you pick or capture a photo in MAUI?

Beginner

Use MediaPicker.Default.PickPhotoAsync to choose from the gallery or CapturePhotoAsync to use the camera (camera requires permission and hardware). Both return a FileResult you can open as a stream to display or upload.

var photo = await MediaPicker.Default.CapturePhotoAsync();
if (photo is not null)
{
    using var stream = await photo.OpenReadAsync();
    // save or display
}

Real-world example A profile screen lets users take a new avatar photo or pick an existing one with a couple of lines.

Common follow-ups: Does capture need permission? | What does PickPhotoAsync return?

Media Permissions Device Features & Essentials

How do you open the browser, dialer, or email from MAUI?

Beginner

Use the launcher/communication APIs: Browser.Default.OpenAsync for URLs, PhoneDialer.Default.Open for phone numbers, Email.Default.ComposeAsync for email, and Sms/Map for others. These invoke the platform's default apps rather than embedding them.

await Browser.Default.OpenAsync("https://w3teacher.com",
    BrowserLaunchMode.SystemPreferred);
PhoneDialer.Default.Open("+15551234567");

Real-world example A contact screen opens the dialer with the support number and launches the website in the system browser.

Common follow-ups: SystemPreferred vs External mode? | How do you compose an email?

Launcher Communication Device Features & Essentials

How do you read device sensors like the accelerometer?

Intermediate

Use the sensor APIs (Accelerometer, Gyroscope, Compass, Barometer). Subscribe to ReadingChanged and call Start with a SensorSpeed, then Stop when done to save battery. Marshal UI updates to the main thread.

Accelerometer.Default.ReadingChanged += (s, e) =>
    Debug.WriteLine(e.Reading.Acceleration);
Accelerometer.Default.Start(SensorSpeed.UI);

Real-world example A fitness app detects shakes and step motion by reading the accelerometer at UI speed and stopping it when the screen closes.

Common follow-ups: Why stop sensors when idle? | What is SensorSpeed?

Sensors Performance & Optimization Device Features & Essentials

How do you get device and display information in MAUI?

Intermediate

Use DeviceInfo (model, manufacturer, platform, version, idiom, DeviceType—physical vs virtual) and DeviceDisplay (screen metrics, density, orientation, keep-screen-on). These help adapt UI and diagnose device-specific issues.

var idiom = DeviceInfo.Current.Idiom;          // Phone/Tablet/Desktop
var density = DeviceDisplay.Current.MainDisplayInfo.Density;
DeviceDisplay.Current.KeepScreenOn = true;

Real-world example A video page keeps the screen awake during playback and adapts controls when it detects a tablet idiom.

Common follow-ups: How do you detect an emulator? | What is display density?

Device Info Responsive UI Device Features & Essentials

How do you use the Clipboard and Share APIs?

Intermediate

Clipboard.Default.SetTextAsync/GetTextAsync copies and reads text. Share.Default.RequestAsync opens the OS share sheet with text or files (ShareTextRequest/ShareFileRequest), letting users send content to other apps.

await Clipboard.Default.SetTextAsync(couponCode);
await Share.Default.RequestAsync(new ShareTextRequest
{ Text = "Check this out!", Title = "Share" });

Real-world example A coupon screen copies the code to the clipboard and offers a Share button to send a referral link to friends.

Common follow-ups: How do you share a file? | Is Clipboard access async?

Clipboard Sharing Device Features & Essentials

How do you run background work or scheduled tasks in MAUI?

Advanced

MAUI has no unified background API; use platform mechanisms: Android WorkManager/foreground services, iOS BGTaskScheduler/background modes, and Windows background tasks—wrapped behind a shared interface. For short async work while active, normal tasks suffice; true background execution needs native scheduling per platform.

public interface IBackgroundSync { void Schedule(TimeSpan interval); }
// Platforms/Android -> WorkManager; Platforms/iOS -> BGTaskScheduler

Real-world example A messaging app schedules periodic sync via WorkManager on Android and BGTaskScheduler on iOS behind one IBackgroundSync interface.

Common follow-ups: Why is there no unified background API? | What handles Android background work?

Background Tasks Platform Integration Device Features & Essentials