CODEWITHSUNDEEP
arduinoesp32
axa
axa

Reputation: 520

How to define the callback for an esp32 arduino ble scan result

The definition to start a BLE scan is:

bool start(uint32_t duration, void (*scanCompleteCB)(BLEScanResults), bool is_continue = false);

The second parameter seems to be the callback when a scan is complete, being somewhat new to this Im unsure how to define it.

fwiw Ive tried this:

void OnScanResults(BLEScanResults scanResults)
{ }

and used it like this:

scanResults = scan->start(60, OnScanResults, true);

but obvious to others, that didnt work.

Please help me decypher that signature 

void (*scanCompleteCB)(BLEScanResults)

Upvotes: 1

Views: 1475

Answers (1)

Tarick Welling
Tarick Welling

Reputation: 3265

you need to add & to OnScanResults because:

void (*scanCompleteCB)(BLEScanResults)

is a pointer to a function which takes a BLEScanResults, returns nothing and is called scanCompleteCB

So your call should be:

scanResults = scan->start(60, &OnScanResults, true);

just as a pointer to a int points to the address of a int

int pointedTo;
int* ptr = &pointedTo;

Upvotes: 3

Related Questions