DeviceUseTrigger Class

Definition

Namespace:

Windows.ApplicationModel.Background

Represents an event that a Windows Runtime app can trigger to initiate a long-running operation with a device or sensor.

DeviceUseTrigger lets your Windows Runtime app access sensors and peripheral devices in the background, even when your foreground app is suspended. For example, depending on where your app is running, it could use a background task to synchronize data with devices or monitor sensors.

This class can be used in UWP app and Windows Phone 8.x app. However, a DeviceUseTrigger background task supports different APIs, and is subject to different policies, depending where it's running (PC or phone). To learn more about these differences, see Accessing sensors and devices from a background task.

Important

This trigger cannot be used with single-process background tasks.

For a sample that shows how to use DeviceUseTrigger on a PC, see the Custom USB device sample. For a phone sample, see the Background Sensors sample.

public ref class DeviceUseTrigger sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
/// [Windows.Foundation.Metadata.Activatable(65536, "Windows.Foundation.UniversalApiContract")]
class DeviceUseTrigger final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
[Windows.Foundation.Metadata.Activatable(65536, "Windows.Foundation.UniversalApiContract")]
public sealed class DeviceUseTrigger

function DeviceUseTrigger()

Public NotInheritable Class DeviceUseTrigger

Inheritance

Object Platform::Object IInspectable DeviceUseTrigger

Attributes

ActivatableAttribute ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

Implements

IBackgroundTrigger

Windows requirements

Device family	Windows 10 (introduced in 10.0.10240.0)
API contract	Windows.Foundation.UniversalApiContract (introduced in v1.0)

Remarks

For more about policy requirements, see Accessing sensors and devices from a background task

Before your app triggers a background task on a phone, it must first call BackgroundExecutionManager.RequestAccessAsync to check if the app is able to request a background task. This check is not required when your app is running on a PC.

Constructors

DeviceUseTrigger()

Constructor for DeviceUseTrigger. Takes no parameters.

Methods

RequestAsync(String, String)	Triggers the background task and returns a DeviceTriggerResult indicating success or failure of the trigger request. Takes the DeviceInformation.ID of the device or sensor that the background task will access, and an optional app-specific string passed to the background task identifying which operation to perform.
RequestAsync(String)	Triggers the background task and returns a DeviceTriggerResult indicating success or failure of the trigger request. Takes the DeviceInformation.ID of the device or sensor that the background task will access.

See also

• IBackgroundTrigger