Manually programming the splash screen to appear at arbitrary times - unity3d

Question

In our app, the splash screen appears when we start the app (or build to Android device) as the app is loading, which is done through the Unity's Edit -> Project Settings -> Player but we now have a feature that sometimes in the middle of the app also re-starts the app, so we would like to code this behavior, so that we can show a different splash screen if the app re-starts mid-usage.
We cannot seem to be able to figure out how to do this programmatically, or where exactly in the app code, so we would appreictae any help.
What we do know (and have already implemented) is through:
PlayerPrefs.SetString("LastShownComponent", menuId);
PlayerPrefs.Save();
which remembers if this is the first time the app is starting (original splash image) or whether the user is mid-usage, but how do we specify another image to be loaded as splash screen when the app is reloading mid-usage?
EDIT: more details...
Previously, we only had the following code:
if (_callbackUri == null)
{
SceneManager.LoadScene("ReloadScene");
}
Now, we force the app to re-start mid-usage (for a specific reason) by:
if (_callbackUri == null)
{
PlayerPrefs.SetInt("Restarting", 1);
PlayerPrefs.Save();
#if UNITY_ANDROID && !UNITY_EDITOR
AndroidPlugin.Restart();
#else
SceneManager.LoadScene("ReloadScene");
#endif
}
However, when it restarts, obviously it re-loads the same splash screen image that is in the player settings.
We probably need to add code just below AndroidPlugin.Restart(); to load a new splash screen image, but how do we do that? Do we need a new scene for that?

Answer 1

Per the comments:
Quickest way to test this is to create a blank scene, add a gameobject to that scene name it something like SplashLoader and give it a script.
the only thing you need in that script is the start method,
void Start()
{
// Default to 0 incase this value isn't stored
int reloaded = PlayerPrefs.GetInt("Restarting", 0);
// Reset to 0 so if the game is closed without restarting it will display the correct scene
PlayerPrefs.SetInt("Restarting", 0);
PlayerPrefs.Save();
if(reloaded == 1)
{
SceneManager.LoadScene("ReloadScene");
}
else
{
SceneManager.LoadScene("SplashScene");
}
}
From here you would create 2 scenes, one for your normal SplashScene and 1 for your ReloadScene. In those scene you can create a canvas object and add an image to it then change the image depending which scene it is.
Another Option if you want to use a single scene and keep the same animation say you have an effect where your logo fades in, you can do this:
Create a scene for your splash screen, make that your 0 index scene, add a canvas to it and an image, then use an animator to get your splash screen effect going.
Add a script to your image object, to change the picture depending on what the preference stores, you can use almost the same code as the start method above, instead of calling the SceneManager to load the scene you would just update the image.

Answer 2

Short answer: you can't.
The splash screen (and everything associated with it) can only be changed/modified inside the editor (via Inspector or via code using the UnityEditor.PlayerSettings.SplashScreen class).
To add insult to injury, on Android you MUST have a splash screen: if you try to disable it via the Player Settings, the Android app won't work.
So, the only solution you have is to use a blank splash screen, and then two different starting scenes (with different backgrounds) which are loaded, mutually exclusively, if you are launching or restarting the app (by using a field in PlayerPrefs as you correctly thought).
EDIT
Actually, you don't even need multiple scenes to accomplish what you want to do.
Create just one scene (let's call it SplashScene), with just the Main Camera and a Canvas with an Image.
Attach this script to the Main Camera:
using UnityEngine;
using UnityEngine.UI;
using System;
public class NewBehaviourScript : MonoBehaviour {
[SerializeField]
Image backgroundImage;
[SerializeField]
Sprite launchBackground, restartBackground;
private void Awake() {
if (!PlayerPrefs.HasKey("Background Splash Screen"))
PlayerPrefs.SetInt("Background Splash Screen", 0);
int background = PlayerPrefs.GetInt("Background Splash Screen");
switch (background) {
case 0:
backgroundImage.sprite = launchBackground;
break;
case 1:
backgroundImage.sprite = restartBackground;
break;
default:
throw new Exception("Invalid Background Splash Screen PlayerPref value!");
break;
}
}
}
Of course SplashScene should be at index 0 in the standalone scenes list.
The only other thing you need to do is to add
PlayerPrefs.SetInt("Background Splash Screen", 0);
before any Application.Quit(); method you call in your project and
PlayerPrefs.SetInt("Background Splash Screen", 1);
before any AndroidPlugin.Restart(); method in your code.
Don't forget to assign the sprites and the image reference to the variables of the script via Inspector ofc (you can get them via GetComponent and asset loading if you prefer, it's up to you).
That's pretty much it. :)