Input Queue

In order to take in input, we're going to be utilizing osMessageQueue, which, as the name implies, allows us to create queues of messages.

For our BoxMover struct, all we need to do is declare an osMessageQueueId_t, which will be an ID for our queue, so we can reference it later.

typedef struct {
    BoxMoverModel* model;

    osMessageQueueId_t event_queue;

    ViewPort* view_port;
    Gui* gui;

} BoxMover;

Now, let's actually create a queue inside of our box_mover_alloc function.

BoxMover* box_mover_alloc(){
    // --snip--
    instance->gui = furi_record_open("gui");

    instance->event_queue = osMessageQueueNew(8, sizeof(InputEvent), NULL);
    
    return instance;
}

The above code creates a new event queue that will hold InputEvents (from the input service).

In its parameters, we define that it will have:

• A maximum of 8 messages in the queue
• A message size of an InputEvent
• Default attributes (specified by NULL)

Let's remember to free this new input queue in box_mover_free:

void box_mover_free(BoxMover* instance){
    // --snip--
    osMessageQueueDelete(instance->event_queue);

    free(instance->model);
    free(instance);
}

Unsure of your code?

Check out the code so far for this section!