How do i pop up a canvas, when a click some key from keyboard?

Hi,

You want to use the 'SetActive' function of your canvas (and to be listening to your keyboard) !

Let's say you wanna use 'E' to interact with the door, you will want to write a script in which as soon as you use the E key, the canvas will be active (and thus visible) and when you press E again, the canvas will be hidden.

C#:

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 // put this script on any gameobject, i personally use an empty 'root' gameobject on which i put all my scripts alike
 public class ToggleDoorCanvas : MonoBehaviour {
     public Canvas doorCanvas;    // now you have to drag and drop your canvas in the editor in the script component
     private bool doorActive = false; // do we have to display the canvas (true) or not (false)
     
     void Update () {
         if(Input.GetKeyDown(Keycode.E)){ // if you press the E key
             doorActive = !doorActive; // change the state of your bool
             doorCanvas.transform.SetActive(doorActive); // display or not the canvas (following the state of the bool)
         }
     }
 }

Now that's not perfect because it will display the canvas wherever you are, far from the door or not, whatever you're doing, pressing E will display the canvas. What you can do to improve the solution:

• Use a 'world canvas' instead of a classic canvas that is stuck on you camera, that will display the canvas 'in the world' like a gameobject: https://www.youtube.com/watch?v=Mzt1rEEdeOI

• Use raycast to fire a limited-range ray in front of you to detect if there's a door or not and if it's the case display the canvas.