Problem with dontDestroyOnLoad in different scene - unity3d

I am making a game that has two scenes (menu scene and game scene). In the menu scene, I create an empty game object just for my music, which includes (audio source (music), button to mute the music, and my script.
Here's the script:
public class Music : MonoBehaviour
{
public static Music Instance;
public AudioSource mainMusic;
public GameObject musicOffImage;
// Keep The Muic Playing In Diffrent Scene
void Awake()
{
if (!Instance)
Instance = this;
else
Destroy(this.gameObject);
DontDestroyOnLoad(this.gameObject);
}
// Method Mute Button
public void MusicOnOff()
{
if (mainMusic.isPlaying)
{
mainMusic.Pause();
musicOffImage.SetActive(true);
}
else
{
mainMusic.UnPause();
musicOffImage.SetActive(false);
}
}
}
With that script, I can play music in different scenes without reloading the music, and the button is working too, but the problem is when I go to the game scene and I back up to the menu scene, somehow the button didn't work. I think it's about the Destroy game object, but I am not sure how to fix it. Any help would mean a lot to me. Thanks.

I assume that everything the Music scripts needs is a child of it so that it is always fine.
However, after Destroy of the instance from the new scene, your buttons from the new scene loose the reference to the Music instance.
Since you have a Singleton there anyway you could as well (ab)use it and have this attached to your button itself
public MusicButton : MonoBehaviour
{
public void MusicOn()
{
Music.Instance.MusicOnOff();
}
}
And reference that instead in your button.
Also the image could e.g. register itself to the Music.Instance like e.g.
public MusicImage : MonoBehaviour
{
private void Start()
{
Music.Instance.musicOffImage = gameObject;
gameObject.SetActive(Music.Instance.mainMusic.isPlaying);
}
}
Alternative
In your question you said all objects are child's of an empty object, however the only object that gets DontDestroyOnLoad is the Music one. The others will get destroyed and reloaded so all these references might get lost as well. You might probably rather DontDestroyOnLoad the entire empty object and only hide/show the button in certain scenes.

Related

Unity: How to switch scenes and when returning to the original scene, return player to the place they switched their scene

I have two scenes: Main Street & Building Scene
When the player is Main Street, if the player's trigger box touches the building and the player presses "q", the scene would switch to the Building Scene.
I want it so that when the player exits the Building Scene and returns to the Main Street Scene, the player is back to the position they entered the Building Scene that they entered from. Apologies in advance if this doesn't make sense.
sceneSwitchingScript:
public int buildingToLoad;
public Text InputText;
public movement player;
public Vector3 playerPrevPos;
void OnTriggerEnter2D(Collider2D col){
if(col.CompareTag("Player")){
InputText.text = ("[Q] to enter");
if(Input.GetKeyDown("q")){
if (gameObject.tag == "EntryPoint"){
playerPrevPos = new Vector3(player.transform.position.x, player.transform.position.y, player.transform.position.z);
}
//Debug.Log(gameObject.tag);
Application.LoadLevel(buildingToLoad);
}
}
}
void OnTriggerStay2D(Collider2D col){
if(col.CompareTag("Player")){
if(Input.GetKeyDown("q")){
//spawn = new Vector3(player.transform.position.x, player.transform.position.y, player.transform.position.z)
Application.LoadLevel(buildingToLoad);
if (gameObject.tag == "EntryPoint"){
playerPrevPos = new Vector3(player.transform.position.x, player.transform.position.y, player.transform.position.z);
}
}
}
}
void OnTriggerExit2D(Collider2D col){
if(col.CompareTag("Player")){
InputText.text = ("");
}
}
Setting the player's position when they exit the building
public switchScene ss;
void OnTriggerStay2D(Collider2D col){
if(Input.GetKeyDown("q")){
if(col.gameObject.CompareTag("ExitPoint")){
transform.position = ss.playerPrevPos;
}
}
}
However, these two scrips do not work and I'm not sure if this is related but when I make the player do the switch scene thing in-game, this error pops up:
NullReferenceException: Object reference not set to an instance of an object
movement.OnTriggerStay2D (UnityEngine.Collider2D col)
This error message mentions the error on this line:
transform.position = ss.playerPrevPos;
With Unity, the traditional loading of a scene was fairly destructive. There was the concept of setting a GameObject as safe by setting it as DontDestroyOnLoad, which, in a way, removed the object from the scene altogether, which protected it from scene loads.
Unity finally properly implemented multiscene editing and loading. It's essentially DDOL, but done properly.
Now you can actually have multiple scenes loaded at the same time. Now, what that allows you to do is to have a "Manager" scene that handles all of the objects that are common between scenes, and only load (and unload) the specific objects required for that individual scene.
You'd use it like this:
SceneManager.LoadScene("YourScene", LoadSceneMode.Additive);
That would load "YourScene" in ADDITION to the currently loaded scene. Likewise, removing a scene is:
SceneManager.UnloadScene("YourScene");
Now, if you have a Manager scene, you can include in your manager scene a script that holds data for each individual scene. As a hacky example, you might have:
public Vector3 InsideSceneLastPosition { get; set; }
Which you then assign to before loading your outside scene. When you load your inside scene again, you can read InsideSceneLastPosition again to reposition your character.
Here's the link to the LoadSceneAsync page at Unity.
There's more to it than that, for instance, you have to listen for the SceneManager.sceneLoaded event to know when you've actually loaded the next scene, so that you can reposition your GameObejcts. You can find information about that here.
You can see multiscene editing my simply dragging multiple scenes from the Project window into you Hierarchy window. All the scenes listed will additively work together. But you'll have to be careful though, as there's another "gotcha" in that you cant reference objects from one scene to another. You can call scripts cross scene, but you won't be able to drag a game object from one scene, into the object field of a component on a different scene. Don't worry, you'll get the hang on it =)

Unity, I have problem with DontDestroyOnLoad to keep tracking in different scence

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.

How to control audio in another scene on/off in unity

I am making a game now, it's almost done. now I am trying to control the audio on and off by button or toggle button.
The problem is, I put my audio source gameobject in the splashscreen that is in the 1st scene. and I put the audio or music button in the Setting scene which is inside the 3rd scene. I already make the c# script to control the audio but when I've tried to insert the AudioSource, but it can't since it's from a different scene. I've tried to put the AudioSource in the same scene but the audio didn't start except I go to settings scene first.
Here is the script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class Music : MonoBehaviour
{
static Music instance = null;
public AudioSource Backsound;
private void Awake()
{
if (instance != null)
{
Destroy(gameObject);
}
else
{
instance = this;
GameObject.DontDestroyOnLoad(gameObject);
}
}
public void backsoundOnOff()
{
AudioSource bgsound = Backsound.GetComponent<AudioSource>();
if (bgsound.mute = true){
bgsound.mute = false;
}
else {
bgsound.mute = true;
}
}
}
You have already solved half the problem by using GameObject.DontDestroyOnLoad
The object does indeed exist in both scenes. Now you just need to fetch it.
In the first scene where the created the object, Change the tag of the object. Instead of using one of the exiting tags, create a new tag for it called something such as "MenuMusic". Make sure you assign it after creating it, unity does not assign it automatically
Now, in the 3rd scene, in the game object that needs to access it, create a private field "_music"
in your Start function, add
void Start() {
_music = GameObject.FindGameObjectsWithTag("MenuMusic");
}
You will now have the same instance of Music from scene 1
I would highly recommend referencing the sound script that you have into some sort of game manager. Usually how i work is i have one generic script that controls a multitude of options that i usually call the GameManager. This sets player controls, visual options and sound. From here you can simply set bool whether the player wants the music on and off. If this option wants to change you can reference the GameManager at any point in any script.
//Game Manager code
public void SoundControl(bool soundOff)
{
If(soundOff == true)
{
//Sound Off Control
}else
{
//Sound on Control
}
}
//Reference to game Manager
GameManager manager;
public void TurnOffSound()
{
//Turn sound off through manager
manager =
GameObject.FindGameObjectWithTag("Manager").GetComponent<GameManager>
().SoundControl(true);
}
I find this to be the easiest way to control any options through one script that you can reference anywhere.

Issue with playing background audio for different scenes in unity3d

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.

UI Buttons Stop Working After I Load Another Scene

I have UI buttons to toggle sound. OnClick event is linked to this singleton GameObject. when I move to the next scene and come back to the main scene, I find OnClick object becomes missing while object is still there in the hierarchy! so what's the problem ?
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class SoundsManagerController : MonoBehaviour {
static SoundsManagerController Instance = null;
void Awake()
{
// First we check if there are any other instances conflicting
if (Instance != null )
{
            // If that is the case, we destroy other instances
            Destroy(gameObject);
}
else {
// Here we save our singleton instance
Instance = this;
// Furthermore we make sure that we don't destroy between scenes (this is optional)
DontDestroyOnLoad(gameObject);
}
}
public void toggleSound(){
Instance.GetComponent<AudioSource> ().enabled = !Instance.GetComponent< AudioSource> ().enabled;
}
}
Use a separate canvas for the button and keep them as child of the singleton object.
If you already have a canvas in the scene, make sure the button is set as child of the canvas whenever your are going to a scene.
When these should be fixing your issue, you should consider not using a button with the singleton object. Get the singleton object in Start() in any scene and access sound toggle from the already placed button which is maintaining your UI layout.
Get the singleton object at start that holding the toggle method calling function.
SoundManagerController soundManager;
void Start ()
{
soundManager = GameObject.FindWithTag("audio_manager_tag").GetComponent <SoundManagerController>();
}
Call the below method from toggle button.
public void CallToggleMethod()
{
soundManager.toggleSound ();
}