Access dual-screen info on Surface Duo from Xamarin.Android

Note

Xamarin.Forms users should check out DualScreenInfo and TwoPaneView in the Xamarin.Forms.DualScreen NuGet.

The Xamarin.DuoSDK is for Xamarin.Android developers targeting the Surface Duo. To target Surface Duo and other foldable devices, see the Jetpack Window Manager binding available in Xamarin.AndroidX.Window.

Hinge Sensor

The HingeSensor class can be used to easily listen for a OnSensorChanged event and get the updated hinge angle value. Add the DuoSDK NuGet to your application before using the Microsoft.Device.Display namespace and HingeSensor class.

using Microsoft.Device.Display;

// ...

HingeSensor hingeSensor;

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

    hingeSensor = new HingeSensor(this);
}

protected override void OnResume()
{
    base.OnResume();

    if (hingeSensor?.HasHinge ?? false)
    {
        hingeSensor.OnSensorChanged += HingeSensor_OnSensorChanged;
        hingeSensor.StartListening();
    }
}

protected override void OnPause()
{
    base.OnPause();

    if (hingeSensor?.HasHinge ?? false)
    {
        hingeSensor.StopListening();
        hingeSensor.OnSensorChanged -= HingeSensor_OnSensorChanged;
    }
}

private void HingeSensor_OnSensorChanged(object sender, HingeSensor.HingeSensorChangedEventArgs e)
{
    Console.WriteLine($"Hinge Sensor Changed: {e.HingeAngle}");
}

IsSurfaceDuoDevice

public bool IsDeviceSurfaceDuo(Context context, string feature = "com.microsoft.device.display.displaymask")
    => context?.PackageManager?.HasSystemFeature(feature) ?? false;

IsAppSpanned

The Xamarin.DuoSdk contains a ScreenHelper class which you can initialize and use to detect if the app is spanned:

public bool IsAppSpanned()
{
    var screenHelper = new ScreenHelper();

    // If initialize returns false, it's not a Duo device, can't be spanned
    if (!screenHelper.Initialize(this))
        return false;

    return screenHelper.IsDualMode;
}

If you want to retrieve the bounds for the location of the hinge mask, you can use the GetHingeBoundsDip() method:

var hingeBoundsRect = screenHelper.GetHingeBoundsDip();

Display Mask

Add the DuoSDK NuGet to use these APIs in your project.

using Microsoft.Device.Display;

Methods

Static methods

Method	Description
FromResourcesRect(Context context)	Creates the display mask according to config_mainBuiltInDisplayMaskRect.
FromResourcesRectApproximation(Context context)	Creates the display mask according to config_mainBuiltInDisplayMaskRectApproximation, which is the closest rectangle-base approximation of the mask.

Object methods

Method	Description
GetBoundingRects()	Returns a list of Rects, each of which is the bounding rectangle for a non-functional area on the display.
GetBoundingRectsForRotation(SurfaceOrientation rotation)	Returns a list of Rects with respect to the rotation, each of which is the bounding rectangle for a non-functional area on the display.
GetBounds()	Returns the bounding region of the mask.

Example

Getting a display mask rect

var displayMask = DisplayMask.FromResourcesRect(context);

var masks = displayMask.GetBoundingRectsForRotation(rotation); // pass in orientation (test with 0)
var mask = new Rect();
if(masks?.Any() ?? false) {
    mask = masks.First();
    // layout around masked area
}

Public methods

FromResourcesRect

public static DisplayMask FromResourcesRect(Context context)

Creates the display mask according to config_mainBuiltInDisplayMaskRect.

Parameters

Context context

A context for the current activity.

Returns

DisplayMask

The new display mask.

FromResourcesRectApproximation

public static DisplayMask FromResourcesRectApproximation(Context context)

Creates the display mask according to config_mainBuiltInDisplayMaskRectApproximation, which is the closest rectangle-base approximation of the mask.

Parameters

Context context

A context for the current activity.

Returns

DisplayMask

The new display mask.

GetBoundingRects

public List<Rect> GetBoundingRects()

Returns a list of Rects, each of which is the bounding rectangle for a non-functional area on the display.

Returns

List<Rect>

A list of bounding Rects, one for each display mask area.

GetBoundingRectsForRotation

public List<Rect> GetBoundingRectsForRotation(SurfaceOrientation rotation)

Returns a list of Rects with respect to the rotation, each of which is the bounding rectangle for a non-functional area on the display.

Parameters

SurfaceOrientation rotation

The rotation mask should rotate. Possible values are SurfaceOrientation.Rotation0, SurfaceOrientation.Rotation90, SurfaceOrientation.Rotation180, SurfaceOrientation.Rotation270.

Returns

List<Rect>

A list of bounding Rects, one for each display mask area.

GetBounds

public Region GetBounds()

Returns the bounding region of the mask.

There may be more than one mask, in which case the returned Region will be non-contiguous and its bounding rect will be meaningless without intersecting it first.

Returns

Region

The bounding region of the mask. Coordinates are relative to the top-left corner of the content view and in pixel units.