Media key

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The Media key API contains the media key library.

Required Header

#include <media_key.h>

Overview

The Media key API provides functions for getting the status of the media key when the key is changed.

Functions
int	media_key_reserve (media_key_event_cb callback, void *user_data)
	Registers a change event callback for all media keys.
int	media_key_release (void)
	Unregisters the change event callback function.
Typedefs
typedef void(*	media_key_event_cb )(media_key_e key, media_key_event_e status, void *user_data)
	Called when the status of the media key is changed.

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Typedef Documentation

typedef void(* media_key_event_cb)(media_key_e key, media_key_event_e status, void *user_data)

Called when the status of the media key is changed.

Since :

2.3

Parameters:

[in]	key	The key whose status is changed
[in]	status	The status of the key
[in]	user_data	The user data passed from the callback registration function

Precondition:

media_key_reserve() will invoke this callback function.

See also:

media_key_reserve()

media_key_release()

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Enumeration Type Documentation

enum media_key_e

Enumeration for media keys.

Since :

2.3

Enumerator:

MEDIA_KEY_PLAY	Play key
MEDIA_KEY_STOP	Stop key
MEDIA_KEY_PAUSE	Pause key
MEDIA_KEY_PREVIOUS	Previous key
MEDIA_KEY_NEXT	Next key
MEDIA_KEY_FASTFORWARD	Fastforward key
MEDIA_KEY_REWIND	Rewind key
MEDIA_KEY_PLAYPAUSE	Playpause key
MEDIA_KEY_MEDIA	Media key for earjack
MEDIA_KEY_UNKNOWN	Unknown key

enum media_key_error_e

Enumeration for error codes of a media key.

Since :

2.3

Enumerator:

MEDIA_KEY_ERROR_NONE	Successful
MEDIA_KEY_ERROR_INVALID_PARAMETER	Invalid parameter
MEDIA_KEY_ERROR_OPERATION_FAILED	Reserve/Release failed

enum media_key_event_e

Enumeration for event statuses of a media key.

Since :

2.3

Enumerator:

MEDIA_KEY_STATUS_PRESSED	Pressed status
MEDIA_KEY_STATUS_RELEASED	Released status
MEDIA_KEY_STATUS_UNKNOWN	Unknown status

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Function Documentation

int media_key_release

(

void

)

Unregisters the change event callback function.

Since :

2.3

Returns:

0 on success, otherwise a negative error value

Return values:

MEDIA_KEY_ERROR_NONE	Successful
MEDIA_KEY_ERROR_INVALID_PARAMETER	Invalid parameter
MEDIA_KEY_ERROR_OPERATION_FAILED	Release key failed

See also:

media_key_reserve()

int media_key_reserve	(	media_key_event_cb	callback,
		void *	user_data
	)

Registers a change event callback for all media keys.

Since :

2.3

Parameters:

[in]	callback	The callback function to invoke
[in]	user_data	The user data to be passed to the callback function

Returns:

0 on success, otherwise a negative error value

Return values:

MEDIA_KEY_ERROR_NONE	Successful
MEDIA_KEY_ERROR_INVALID_PARAMETER	Invalid parameter
MEDIA_KEY_ERROR_OPERATION_FAILED	Reserve key failed

See also:

media_key_release()