How to make a live counter in unity3d - unity3d

Question

I recently started using Unity3D and made a few levels. The only problem I have right now is how can I get a live counter?
So my character dies when he hits and certain object.
I want my character to get 3 lives maximum, and get -1 live when he hits that object.
And that it keeps the data when he dies so you wouldn't get lives back if you restart the app.
And after a certain amount of minutes he gets +1 live.
Thank you :)

Answer 1

While your game running. just create a variable counterTime to count time, whenever counterTime pass certain amount of time you want reset counterTime to 0 and increase your life.
When user quit your app, save last time to PlayerPref, eg:
PlayerPref.SaveString("LastTime", DateTime.Now);
When user comback game, just check duration between last time and now to calculate total life need added. eg:
DateTime lastTime = DateTime.Parse(PlayerPref.GetString("LastTime"));
TimeSpan timeDif= DateTime.Now - lastTime;
int duration = timeDif.TotalSeconds;

Answer 2

You can use PlayerPrefs.SetInt , PlayerPrefs.GetInt for storing and reading your player's hp in file storage. Read more about it here:
https://docs.unity3d.com/ScriptReference/PlayerPrefs.html
As for Giving player +1 hp after a few minutes you can store DateTime.Now in a PlayerPrefs variable whenever you give your player some hp and use TimeSpan and TotalMinutesPassed:
TimeSpan passedTime = DateTime.Now - lastStoredDateTime;
int totalMinutesPassed = passedTime.TotalMinutes;
Should go sth like this i guess(didnt test this code just showing a general idea) :
void SetPlayerLives(int lives)
{
playerLives = lives;
PlayerPrefs.SetInt("player-lives",playerLives);
}
//TODO: also sth like => int GetPlayerLives() function
void CheckLiveRegen() //call this function whenever you want to check live regen:
{
int LIVE_REGEN_MINUTES = 5; //regen 1 live every 5 minutes
DateTime lastStoredDateTime = DateTime.Parse(PlayerPrefs.GetString("last-live-regen", DateTime.Now.ToString()));
TimeSpan passedTime = DateTime.Now - lastStoredDateTime;
double totalMinutesPassed = passedTime.TotalMinutes;
if(totalMinutesPassed >= LIVE_REGEN_MINUTES)
{
int val = (int) totalMinutesPassed / LIVE_REGEN_MINUTES;
// Add val to your player lives! + store new lives value
SetPlayerLives(playerLives+val);
//update last-live-regen value:
PlayerPrefs.SetString("last-live-regen", DateTime.Now.ToString());
}
}
Note: DateTime , TimeSpan classes have some bugs (specially in android platform) in versions older than 2017.4 (LTS) Make sure you log values and check if functions are working properly.
https://forum.unity.com/threads/android-datetime-now-is-wrong.488380/

Answer 3

check out the following link to understand how to create a life counter in unity
http://codesaying.com/life-counter-in-unity/
In order to calculate the time that was lapsed since you last shut down the game, you should save the last time playerprefs in the function OnApplicationPause and calcuate the timelapsed in the Awake Function.
void Awake () {
if(!PlayerPrefs.HasKey("Lives")){
PlayerPrefs.SetString("LifeUpdateTime", DateTime.Now.ToString());
}
lives = PlayerPrefs.GetInt("Lives", maxLives);
//update life counter only if lives are less than maxLives
if (lives < maxLives)
{
float timerToAdd = (float)(System.DateTime.Now - Convert.ToDateTime(PlayerPrefs.GetString("LifeUpdateTime"))).TotalSeconds;
UpdateLives(timerToAdd);
}
}
void UpdateLives(double timerToAdd ){
if (lives < maxLives)
{
int livesToAdd = Mathf.FloorToInt((float)timerToAdd / lifeReplenishTime);
timerForLife = (float)timerToAdd % lifeReplenishTime;
lives += livesToAdd;
if (lives > maxLives)
{
lives = maxLives;
timerForLife = 0;
}
PlayerPrefs.SetString("LifeUpdateTime", DateTime.Now.AddSeconds(-timerForLife).ToString());
}else{
PlayerPrefs.SetString("LifeUpdateTime", DateTime.Now.ToString());
}
}
void OnApplicationPause(bool isPause)
{
if (isPause)
{
timeOfPause = System.DateTime.Now;
}
else
{
if(timeOfPause == default(DateTime)){
timeOfPause = System.DateTime.Now;
}
float timerToAdd = (float)(System.DateTime.Now - timeOfPause).TotalSeconds;
timerForLife += timerToAdd;
UpdateLives(timerForLife);
}
}
}