Clickable AND draggable object

Questions & Answers
1

I have a few objects which I can drag around the screen using the methods OnMouseDown() and OnMouseDrag(). I want to make those objects a button too, that is to click/touch them quickly so they do their own stuff.

I can imagine a simple way measuring the time between OnMouseUp() and OnMouseDown() but I will probably end up wasting energy fixing bugs for something that might be already done…

So is there an specific method to recognize a click? Obviously without altering the dragging capability.

2

No, you need to specify the “Click” conditions yourself.
What happens if I hold the mouse down over the object for 10 seconds, don’t move it, and then release; is this a click?

For some Designers, yes, for your suggested method, no.

To make a draggable-button, personally I would use a boolean flag, and make MouseUp activate a Click, unless(check then clear flag) an OnDrag operation was initiated(clear flag), since the last mouseDown (set flag).

I might also define the behavior a bit differently if the button was NOT also draggable (e.g. only click if mouse is still over the button, during MouseUp). Certainly, some designers might disagree with that, it’s a matter of taste.

3

Since some people including me like to see coding, I came to post the simple couple of lines I used. No dragging flags, so an eventual really quick dragging could be detected as a click. Anyway the workaround would be setting a smaller threshold.

private float init;
[SerializeField] private float clickThreshold = 0.2f;
// stuff

void OnMouseDown () {
  init = Time.time;
  // more stuff
}

void OnMouseUp () {
  if (Time.time - init < clickThreshold) {
    Click ();
  }
  // click-unrelated stuff
}

void Click () {
  // click stuff
}