Change GameObject According to UI selection

Questions & Answers
1

Hey! I am currently working on a racing game and sitting at at the car selection screen. here is my current code:

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class SlotSelector : MonoBehaviour {
	public RectTransform navigator1;
	int nav1Pos = 0;
	public RectTransform navigator2;
	int nav2Pos = 0;
	
	public RectTransform[] slots = new RectTransform[12];
	public int jumpAmount = 4;
	public Text textShowNav1;
	public Text textShowNav2;
	void Start(){
		MoveNav1(0);
		MoveNav2(0);
	}
	void Update () {
		// move up
		if(Input.GetKeyDown(KeyCode.W)){
			MoveNav1(-jumpAmount);
		}
		if(Input.GetKeyDown(KeyCode.UpArrow)){
			MoveNav2(-jumpAmount);
		}
		
		if(Input.GetKeyDown(KeyCode.A)){
			MoveNav1(-1);
		}
		if(Input.GetKeyDown(KeyCode.LeftArrow)){
			MoveNav2(-1);
		}
		
		if(Input.GetKeyDown(KeyCode.S)){
			MoveNav1(jumpAmount);
		}
		if(Input.GetKeyDown(KeyCode.DownArrow)){
			MoveNav2(jumpAmount);
		}
		
		if(Input.GetKeyDown(KeyCode.D)){
			MoveNav1(1);
		}
		if(Input.GetKeyDown(KeyCode.RightArrow)){
			MoveNav2(1);
		}
	}
	
	void MoveNav1(int change){
		if(change > 0){
			if(nav1Pos+change < slots.Length-1){
				nav1Pos += change;
			}else{
				nav1Pos = slots.Length-1;
			}
		}else{
			if(nav1Pos+change >= 0){
				nav1Pos += change;
			}else{
				nav1Pos = 0;
			}
		}
		navigator1.position = slots[nav1Pos].position;
		textShowNav1.text = "Nav 1 is at slot "+ nav1Pos;
	}
	
	void MoveNav2(int change){
		if(change > 0){
			if(nav2Pos+change < slots.Length-1){
				nav2Pos += change;
			}else{
				nav2Pos = slots.Length-1;
			}
		}else{
			if(nav2Pos+change >= 0){
				nav2Pos += change;
			}else{
				nav2Pos = 0;
			}
		}
		navigator2.position = slots[nav2Pos].position;
		textShowNav2.text = "Nav 2 is at slot "+ nav2Pos;
	}
}

which looks in game like this:
… cant upload gif, so here a direct link: GIF | Gfycat

what i want to do now is, that, every time i switch to another slot and press the Enter Key, the Car on the left (the pizza wagon) changes to another Car prefab.
do you guys have an idea how i can do this? Thanks!

2

In your SlotSelector script, add a reference to a placeholder prefab that will display the car. ex. public GameObject blee; Drag CarDisplay prefab onto the variable in editor.

When you move, call a script that has either an id or a model to display:
blee.GetComponent<CarDisplay>().changeCar(int id); or something like that.
Cheers

[edit] It seems you are already doing exactly that and I misunderstood what you where looking for. Use an empty prefab, that spawns or destroys objects when you change cars. Here is a pseudo code for you, I did not test this but it should give you a very clear idea of what I mean:

// Also holds cars in an array of GameObjects
GameObject selectedCar;

void changeCar(int id) {
// Remove previously selected car
Destroy(selectedCar);

// Create object
selectedCar = Instantiate(myCars[id], new Vector3(0,0,0), Quaternion.identity) as GameObject;
}

More info: Unity - Scripting API: Object.Instantiate
and: Unity - Scripting API: Object.Destroy

IIRC, the gameObject may be destroyed at the next frame. So you might want to either use LateUpdate for spawning with some toggle, or use a coroutine to similar effect.

3

You will need to add the following code to your current class to do it,

void Update () {
     //... all ur existing code
    if( /*<enter is pressed condition>*/ ){
         selectNav1(nav1Pos);
    }
}
public Transform[] cars; // all 12 cars meant to be shown, can be set from inspector
public Transform displayAt; // the position where the car is supposed to be displayed
public Transform selectedCar;// the car which is currently being displayed

void selectNav1(int nav1Pos){
      selectedCar.gameObject.SetActive(false); //deactivate the previously selected car
      selectedCar = cars[nav1Pos]; // assign the selected car
      selectedCar.position = displayAt.position; //move it to correct position
      selectedCar.gameObject.SetActive(true); // set the car active
}

will come back later to add more details