SDLSubscribeButton Class Reference

Section Contents

• -initWithHandler:
• -initWithButtonName:handler:
• handler
• buttonName

Overview

Establishes a subscription to button notifications for HMI buttons. Buttons are not necessarily physical buttons, but can also be “soft” buttons on a touch screen, depending on the display in the vehicle. Once subscribed to a particular button, an application will receive both SDLOnButtonEvent and SDLOnButtonPress notifications whenever that button is pressed. The application may also unsubscribe from notifications for a button by invoking the SDLUnsubscribeButton operation

When a button is depressed, an SDLOnButtonEvent notification is sent to the application with a ButtonEventMode of BUTTONDOWN. When that same button is released, an SDLOnButtonEvent notification is sent to the application with a ButtonEventMode of BUTTONUP

When the duration of a button depression (that is, time between depression and release) is less than two seconds, an SDLOnButtonPress notification is sent to the application (at the moment the button is released) with a ButtonPressMode of SHORT. When the duration is two or more seconds, an SDLOnButtonPress notification is sent to the application (at the moment the two seconds have elapsed) with a ButtonPressMode of LONG

The purpose of SDLOnButtonPress notifications is to allow for programmatic detection of long button presses similar to those used to store presets while listening to the radio, for example

When a button is depressed and released, the sequence in which notifications will be sent to the application is as follows:

For short presses:

• OnButtonEvent (ButtonEventMode = BUTTONDOWN)
• OnButtonEvent (ButtonEventMode = BUTTONUP)
• OnButtonPress (ButtonPressMode = SHORT)

For long presses:

• OnButtonEvent (ButtonEventMode = BUTTONDOWN)
• OnButtonEvent (ButtonEventMode = BUTTONUP)
• OnButtonPress (ButtonPressMode = LONG)

HMILevel needs to be FULL, LIMITED or BACKGROUND

Since SmartDeviceLink 1.0
See SDLUnsubscribeButton

- (nonnull instancetype)initWithHandler:
    (nullable SDLRPCButtonNotificationHandler)handler;

init(handler: SDLRPCButtonNotificationHandler? = nil)

- (nonnull instancetype)
    initWithButtonName:(nonnull SDLButtonName)buttonName
               handler:(nullable SDLRPCButtonNotificationHandler)handler;

init(buttonName: SDLButtonName, handler: SDLRPCButtonNotificationHandler? = nil)

@property (nonatomic, copy) SDLRPCButtonNotificationHandler _Nonnull handler;

var handler: SDLRPCButtonNotificationHandler { get set }

@property (nonatomic, strong) SDLButtonName _Nonnull buttonName;

var buttonName: SDLButtonName { get set }