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fuchsia.ui.policy

PROTOCOLS

DeviceListenerRegistry

Defined in fuchsia.ui.policy/device_listener.fidl

Service for exposing state and events of devices, such as media buttons.

RegisterMediaButtonsListener

Registers a listener to receive media button related events, such as changes from volume buttons and mute switches.

Request

NameType
listener MediaButtonsListener

DisplayBacklight

Defined in fuchsia.ui.policy/display_backlight.fidl

Manipulates global policy for display backlight. Serves as the main "front end" interface for usage by UX components; other protocols (such as fuchsia.ui.scenic.Session and fuchsia.hardware.display.Controller) act as implementation.

Global Scope. All displays, in all display controllers, are affected uniformly.

Effect Timing. This protocol does not guarantee a deadline by which the minimum value is applied to a display; it is best effort.

Multiple clients. This protocol does not guarantee unique access to manipulate display backlight functionality.

Reference. Related to fuchsia.hardware.display.Controller.

SetMinimumRgb

Submits a new minimum color channel value for display backlight.

The valid range for a minimum value is [0, 255] (inclusive). For a new minimum value M, each color channel's range will be limited to [M, 255].

Flow control: The caller is allowed at most one in-flight |SetMinimumRgb| at at time. Subsequent calls must wait until the acknowledgment returns. Non-compliance results in channel closure.

Request

NameType
minimum_rgb uint8

Response

NameType

MediaButtonsListener

Defined in fuchsia.ui.policy/device_listener.fidl

A listener for media buttons events. DeviceListenerRegistry.RegisterMediaButtonsListener will consume this listener interface and call OnMediaButtonsEvent when the registered media buttons event occurs.

OnMediaButtonsEvent

Request

NameType
event fuchsia.ui.input/MediaButtonsEvent

PointerCaptureListenerHACK

Defined in fuchsia.ui.policy/presentation.fidl

Presentation.CapturePointerEvent will consume this listener interface and call OnEvent when a pointer event occurs.

OnPointerEvent

Request

NameType
event fuchsia.ui.input/PointerEvent

Presentation

Defined in fuchsia.ui.policy/presentation.fidl

Allows clients of Presenter.Present() to control a presentation. Experimental.

CapturePointerEventsHACK

This call exists so that base shell can capture pointer events.

Request

NameType
listener PointerCaptureListenerHACK

Presenter

Defined in fuchsia.ui.policy/presenter.fidl

The Presenter service provides a way for applications to ask that a view be added to a view tree, leaving any window management concerns up to the discretion of the presenter implementation.

PresentOrReplaceView

Request that the View's contents be displayed on the screen as a Presentation. Destroys any existing presentations and replaces them with the new one. This is true whether the existing view was created by a call to PresentOrReplaceView or to PresentView.

Request

NameType
view_holder_token fuchsia.ui.views/ViewHolderToken
presentation_request request<Presentation>?

PresentView

Request that the View's contents be displayed on the screen as a Presentation. Each call to PresentView creates a new Presentation. Having more than one simultaneous Presentation (i.e. calling PresentView more than once) is deprecated, and will print a warning. In the future, this will result in an error and the channel being closed.

Request

NameType
view_holder_token fuchsia.ui.views/ViewHolderToken
presentation_request request<Presentation>?

STRUCTS

ENUMS

DisplayUsage

Type: uint32

Defined in fuchsia.ui.policy/display_usage.fidl

Describes the intended usage of the display.

NameValueDescription
kUnknown 0
kHandheld 1

Display is held in one or both hands.

kClose 2

Display is used well within arm's reach.

kNear 3

Display is used at arm's reach.

kMidrange 4

Display is used beyond arm's reach.

kFar 5

Display is used well beyond arm's reach.