I have two cs files, Main.cs and Menu.cs. On OnGUI event which is in Main.cs file I call method from Menu.cs.
private void OnGUI()
{
Menu menu=new Menu();
menu.Create_Menu();
}
And in Menu.cs.
public void Create_Menu ()
{
StartCoroutine(LoadCar());
}
private IEnumerator LoadCar()
{
//Load Object
Download download;
download=new Download();
GameObject go = null;
yield return StartCoroutine(LoadAsset("http://aleko-pc/3dobjects?key=1017&objecttype=1","car13",(x)=>{go = x;}));
}
I get error NullReferenceException
UnityEngine.MonoBehaviour.StartCoroutine (IEnumerator routine)
If I copy private IEnumerator LoadCar() method in Main.cs class, and call from OnGUI it works.
Maybe I do not understant working area of Coroutines, Can any body help me?
First of all the OnGUI method is called every frame and I don't think you want to download the assets every frame.
Second, you need to make sure Menu is derived from MonoBehviour and added to the view hierarchy.
A better approach would be to add Menu as a component to a GameObject (maybe the same that has the Main script attached) and call Create_Menu on the Start method of Menu.
Related
What I want:
I want the player to be able to click on instantiated objects and get points, then have those points show in the score-keeping text.
What I’ve done:
I’m currently using the following “FindGameObjectsWithTag” code to retrieve the buttons that are components of the instantiated prefab objects:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using TMPro;
public class CPointScore : MonoBehaviour
{
public TextMeshProUGUI CPointsText;
private float ScoreNum;
private GameObject[] CButtonGmeObjsHolder;
private void CTagFinder()
{
CButtonGmeObjsHolder = GameObject.FindGameObjectsWithTag("Ctag");
foreach (GameObject CButtonGmeObj in CButtonGmeObjsHolder)
{
Debug.Log("GmeObj Found");
Button CButton = CButtonGmeObj.GetComponent<Button>();
CButton.onClick.AddListener(AddScore);
}
}
public void AddScore()
{
ScoreNum += 1;
Debug.Log("Point Added # " + ScoreNum);
}
void Start()
{
InvokeRepeating("CTagFinder", 1f, 15.1f);
}
void Update()
{
CPointsText.text = ScoreNum.ToString();
}
}
Because FindGameObjectsWithTag only calls once I have the InvokeRepeating code in start. I have game objects spawning throughout the duration of the game so it needs to be constantly checking for tags.
Issue:
So the code finds the tags, the buttons are able to be clicked, and the score-keeping text updates which is great. The problem is that if I click one tagged button it will register a point for itself and every tagged button currently in the scene that spawned after it. For example, lets say I have 4 spawned objects currently on scene, when the first object spawned is clicked it will add 4 points instead of 1. If the second object spawned is clicked it will add 3 points instead of 1. I would like to have only the tagged button that is clicked register a point.
Question:
What can I change in my code so that only the tagged button that is clicked registers a point?
Thank you
I think there are two things here:
You repeatedly add the listener so you will end up with multiple callbacks when the button is finally clicked.
The repeated FindGameObjectsWithTag is also quite inefficient
Your main issue is the repeated calling.
For each repeated call of CTagFinder you go through all existing buttons and do
CButton.onClick.AddListener(AddScore);
so these existing buttons end up with multiple listeners attached!
You either want to make sure it is only called once per button, e.g. keeping track of those you already did this for:
private readonly HashSet<Button> alreadyRegisteredButtons = new HashSet<Button>();
and then
if(!alreadyRegisteredbuttons.Contains(CButton))
{
CButton.onClick.AddListener(AddScore);
alreadyRegisteredButtons.Add(CButton);
}
or alternatively make sure you remove the callback before you add it like
CButton.onClick.RemoveListener(AddScore);
CButton.onClick.AddListener(AddScore);
In general I would not use FindGameObjectWithTag an poll objects repeatedly. Rather make your code event driven. This would already avoid the issue at all since there would be no repeated attaching of the listener anyway.
I would simply have a dedicated component YourComponent attached to the same GameObject as the buttons and have a global
public static event Action<YourComponent> OnCTSButtonSpawned;
and in this dedicated component do
private void Start()
{
OnCTSButtonSpawned?.Invoke(this);
}
and in your CPointScore listen to this event like
private void Awake()
{
YourComponent.OnCTSButtonSpawned += AttachListener;
}
private void AttachListener(YourComponent component)
{
if(compoenent.TryGetComponent<Button>(out var button))
{
button.onClick.AddListener(AddScore);
}
}
private void AddScore()
{
ScoreNum++;
CPointsText.text = ScoreNum.ToString();
}
I have an issue with my In App Purchases manager. I load my scene and can successfully purchase items. I go to a new scene in game and then back to that scene and now it says...
`MissingReferenceException: The object of type 'IAPManager' has been destroyed but you are still trying to access it.
Your script should either check if it is null or you should not destroy the object.`and then points my to this line
moneyController = GetComponent<MoneyController>();
Why does it crash at that point? Do I need to add DontDestroyOnLoad or something? I'm not familiar with that or how to use it though. Am I missing something simple?
Here are some more code snippets that may or may not prove useful. This code is from a tutorial hence why it's difficult for me to pin point the issue.
public static IAPManager Instance{set;get;}
private void Awake() {
Instance = this;
}
you have to put in DontDestroyOnLoad this way you will not get any error for same. below is the code that you can use.
private static IAPManager instance;
public static IAPManager Instance
{
get
{
if (instance == null)
{
GameObject o = new GameObject ("IAPManager");
instance=o.AddComponent<IAPManager>();
DontDestroyOnLoad (o);
}
return instance;
}
}
im new in unity and i have a problem
I am making a game that have 2 scence(Main Menu Scence and Game Scence), i put my music on Main Menu scence. I make a empty game object and i attach audio source there(music) , and i also attach script like this :
First script
public static KeepTheMusicOn Instance;
void Awake()
{
if (!Instance)
Instance = this;
else
Destroy(this.gameObject);
DontDestroyOnLoad(this.gameObject);
}
With that script i can keep music play in second scence wihtout restart the music, and in the main menu scence i have settings that have button to mute the music , the button will run my second script .
Second Script:
public AudioSource mainMusic;
public void Update()
{
DontDestroyOnLoad(mainMusic);
}
public void MusicOnOff()
{
if (mainMusic.isPlaying)
{
mainMusic.Pause();
}
else
{
mainMusic.UnPause();
}
}
My problem is when i start the game so im in my main menu scence i can mute the music with the button, but when i go to game scence and i back to menu, the button dont do anything.
So that is my problem, i hope anyone can help me. Sorry for my bad english.
Sounds like when switching scenes you destroy the button. When you them go back to the main menu you destroy the duplicate instance of your audio controller thing => references configured in the Button are lost.
In your case since you use a public Singleton anyway you could as well (ab)use it and put a component on the Button itself instead (thus the reference can not get lost) and do something like e.g.
[RequireComponent(typeof(Button))]
public class MusicButton : MonoBehaviour
{
[SerializeField] private Button button;
private void Awake()
{
if(!button) button = GetComponemt<Button>();
// dynamically add the callback
// it won't appear in the editor but get called in onClick
button.onClick.AddListener(OnClicked);
}
private void OnClicked()
{
KeepTheMusicOn.Instance.MusicOnOff();
}
}
If you prefer seeing it in the editor you can ofcourse as well rove it from Awake, make the OnClicked public and reference it in the button's onClick event manually.
I have my own custom UnityEvent and am trying to add a listener.
I have used AddListener on numerous other UI objects, such as buttons, dropdowns, toggles, etc. so I understand the process. However, when I Invoke my UnityEvent, it simply doesn't fire.
I'm receiving no error messages, and after doing reading and research, everything looks correct. So, not sure what to do further.
This is an object that emits when it's rotated.
This is the basics of my code:
using UnityEngine.Events;
public class Rotator: MonoBehaviour
{
public UnityEvent OnRotate;
int angle = 0;
int newAngle = 0;
void Start()
{
OnRotate = new UnityEvent();
}
void Update()
{
newAngle = (int)transform.rotation.eulersAngles.z;
if (newAngle != angle)
{
print ("Actual Instance ID: " + GetInstanceID());
print ("Invoking!");
OnRotate.Invoke();
angle = newAngle;
}
}
}
and
public class Owner: MonoBehaviour
{
public Rotator rotator;
void Start()
{
print ("Rotator Instance ID: " + rotator.GetInstanceID());
rotator.OnRotate.AddListener(
() => UpdateRotation()
);
}
void UpdateRotation()
{
print ("Invoked!");
}
}
When the Rotator has it's angle changed, I get this in the console:
Actual Instance ID: 11234
Rotator Instance ID: 11234
Invoking!
The instance ID is to make sure I'm working with the same objects and not going in circles for nothing. They match, so I'm listening to the object that's firing.
However, the listener isn't firing. I've tried different combinations with delegates, etc. but it's all the same. No errors. It just doesn't invoke.
Obviously, I'm doing something wrong, but what is it?
Thanks for any help.
Somehow your answered your new edited version of the question with exactly the code you previously provided in the First Version of your Question!
As I tried to tell you ... if you anywhere in your code do OnRotate = new UnityEvent() of course you thereby erase any persistent callbacks and any runtime callbacks added before that moment!
In short
Simply leave it as
public UnityEvent OnRotate;
and you don't even have to think about it anymore.
For understanding why it also works if you put it in Awake please simply have a look at the Order of Execution for Event Functions
→ First Awake and OnEnabled is called for every GameObject/Component. Then all Start methods are called as soon as the GameObject/Component is active.
Within each of these blocks (Awake + OnEnable) and (Start) the order of execution between different component types is not guaranteed unless you explicitly configure it via the Script Execution Order Settings where you could define that Owner is simply run before Rotator .. then having both in Start would also work again.
Why does it also work if you do it on the public field?
→ Because this field is serialized. That means it is initialized automatically in the Inspector and then stored together with the Scene or prefab asset including any persistent callbacks.
And then Later Unity re-uses the serialized Version of the field so actually you can completely remove the new UnityEvent(); since it doesn't have any effect on a serialized field! It will always be initialized automatically anyway!
Ok, I found out what the issue was.
My question now is "why?".
I changed my code from:
public UnityEvent OnRotate;
void Start() {
OnRotate = new UnityEvent();
}
to
public UnityEvent OnRotate = new UnityEvent();
void Start() {
}
And now it works.
Although, now that I think about it, Awake() is the method where they all fire before initialization, whereas Start() is when the object is created. So the Start() of the Rotator is probably getting called after the Owner is adding a listener.
In my game, I have two scene.
What I want to achieve is if user navigates from one scene to another, background audio specific to each should be played from start(audio length=0)
But all my efforts are in vain.
I tried using 'Pause' Method of audioSound
I tried
create a new game object and assign this scene background score to it and play
destroy gameObject created for another scene if there was any
But it doesn't give the result that I want.
I searched for finding how to play audioClip from start and stop other audioClip playing but didn't find any.
I know I'm not supposed to ask for code on stack overflow but if anyone has achieved this or has some pseudo code request you to provide it
I'm not sure I understand your question properly, since it seems the simplest scenario for background music.
If you really want a change of audioclip in every scene, let's say Scene A must play Clip A and Scene B must play Clip B, and both clips should be played as soon as a scene is loaded, you just need to create a game object in both scenes with an Audio Source component, with the Play On Awake flag active, and then just assign the appropriate clip for the scene (i.e.: assign Clip A in the Audio Clip field of the Audio Source component of Scene A game object, and do the same with Clip B for Scene B).
That's pretty much it.
If you looking at the detail code then you can try this code.
First : Make a script "SoundFxScript.cs" // You can modified as you want
Insert this code :
public class SoundFxScript : MonoBehaviour {
//Background Music
public AudioSource Scene1_Sound;
public AudioSource Scene2_Sound;
// Use this for initialization
void Start () {
PlayBackgroundMusic ();
}
// Update is called once per frame
void Update () {
}
public void PlayBackgroundMusic() {
if (UnityEngine.SceneManagement.SceneManager.GetActiveScene ().name == "Scene1") {
Scene1_SoundPlay();
} else if (UnityEngine.SceneManagement.SceneManager.GetActiveScene ().name == "Scene2") {
Scene2_SoundPlay();
}
}
public void Scene1_SoundPlay() {
Scene1_Sound.Play ();
Scene2_Sound.Stop ();
}
public void Scene2_SoundPlay() {
Scene1_Sound.Stop ();
Scene2_Sound.Play ();
}
// Step Fifth
public void LoadTheScene (string Scenename) {
UnityEngine.SceneManagement.SceneManager.LoadScene (Scenename);
sf.PlayBackgroundMusic ();
}
}
Second : Make Gameobject name = "SoundMusic" at the first scene and add component script SoundFxScript.cs. In gameobject "SoundMusic" you can add you background music for scene1 and scene2.
Third : Make a singleton file Singleton.cs
Insert this code :
public class Singleton : MonoBehaviour {
static Singleton instance = null;
void Start ()
{
if (instance != null)
{
Destroy(gameObject);
return;
}
DontDestroyOnLoad(gameObject);
instance = this;
}
}
Fourth : at gameobject "SoundMusic" add component script "Singleton.cs"
Fifth : How To Call In Another Scene (Load Scene). This method is inside SoundFxScript.cs
Example You have a method to call a load scene. Try this method :
Call it with : LoadTheScene("Scene2") // Call scene2
In here you can call your SoundFxscript.cs Component from any script you have.
Example :
SoundFxScript sf;
sf = GameObject.Find ("SoundMusic").GetComponent<SoundFxScript> ();
And you can use method LoadTheScene to load a new scene and the background music will RePlay again according to the what Scene is it.
That's All.