How to check if finger is touching the screen using the Unity input system?

Question

I have a While loop that runs when the mouse is pressed and it look like this:

while (mouseClick.ReadValue<float>() != 0)
{
   //Do something
}

This works but I want this to work on mobile instead so I am trying to change this to when a finger is touching the screen. I tried this code:

    while (touchControls.Touch.TouchPosition.ReadValue<Vector2>() != Vector2.zero)
    {
        //Do something
    }

That loop starts to run when a finger presses the screen, but it never stops. And touchControls.Touch.ReadValue() != 0 didn't work either. So how can I make it work like I want?

Thanks.

Answer 1

One way is to access the InputSystem more directly.

You might be looking for TouchPhase or use the Finger combined with the EnhancedTouch.

using UnityEngine;
using UnityEngine.InputSystem.EnhancedTouch;
using Touch = UnityEngine.InputSystem.EnhancedTouch.Touch;

public class TouchDemo : MonoBehaviour
{
    private void OnEnable()
    {
        EnhancedTouchSupport.Enable();
    }

    private void OnDisable()
    {
        EnhancedTouchSupport.Disable();
    }

    private void Update()
    {
        foreach (var touch in Touch.activeTouches)
        {
            // Only respond to first finger
            if (touch.finger.index == 0 && touch.isInProgress)
            {
                // TODO
            }
        }
    }
}

Edit: See the Touch struct for more information about the various states of a Touch.