KeyCode's from Events acting strange?

Unity Engine
1

I was setting up a double-tap(-hold) mechanism for my keyboard keys. Decided I’d use the Events in OnGUI for capturing my KeyDowns, rather than using Input, since this way I could fetch which button was pressed.

So I went about this like so

if (currentEvent.type == EventType.KeyDown) {
	float currentTime = Time.time;
	KeyCode currentKey = currentEvent.keyCode;
	if (!doubleTapped  currentKey == lastKeyPressed  currentTime <= (timeOfLastKeyPress + doubleTapTimeThreshold)) {
		doubleTapped = true;
	}
	timeOfLastKeyPress = currentTime;
	lastKeyPressed = currentKey;
}
else if (currentEvent.type == EventType.KeyUp) {
	doubleTapped = false;
}

Worked pretty alright, for the arrow keys atleast. But when testing other keys, I found some strange behaviour.
Alphabet keys for instance, wouldn’t doubletap this way.

So I set up this simple test

void OnGUI()
{
	Event currentEvent = Event.current;
	if (currentEvent.isKey  currentEvent.type == EventType.KeyDown) {
		Debug.Log(currentEvent.keyCode);
	}
}

Throw it on an empty object and try it out.
Arrow keys, pagedown, and some others work as expected. But Space, Enter, and alphabet keys result in 2 debug lines. The first is the correct KeyCode enum, and the second holds ‘None’. So that’s a second event somehow, and a faulty KeyCode to boot.

This can’t be desired behaviour…

And on a side note: Since this does not seem to be working, how would I go about ‘enabling’ double tapping for n-number of keys?
Say ‘DidIRegisterADoubleTap(KeyCode pressedKey) { /magic?/ }’ ?

edit: Also it is important to note that while Input.GetKeyDown(keyCode) only returns true once; the first frame in which the key was pressed. Where EventType.KeyDown gets triggered once upon first pressing the key, and then repeatedly triggers when holding (same default windows behaviour when press/holding a key).
In fact the behaviour from the Input variant would be desired over the other…

2

You can use Input.inputString to tell you which key is pressed. Using OnGUI input for non-OnGUI events seems iffy.

–Eric

3

Yeah I kinda felt the same way. But from the reference docs I understood Input.inputString returns all keys being pressed that frame. I kind of dismissed it because that would complicate things when pressing multiple buttons at once.
I guess I could maybe parse the string…

Heck I’ll atleast try it out before I ramble on any further.

Alright a quick test reveals Input.anyKeyDown and Input.inputString actually work much better than expected.
I was worrysome about anyKeyDown’s “It will not return true until the user has released all keys / buttons and pressed any key / buttons again.”, but it seems that that statement is not entirely true.

The only problem left now is that I can only capture ‘string’ input, which leaves out things like arrow keys and such.
I’ll just have to write two seperate bits of code for double taps: one for movement/InputAxis, and the other for aphabetical keys.

Thanks.
Sal