Unity script lifecycle day02

What is a script lifecycle ？

Unity The process of script from wake-up to destruction .

news ： When certain conditions are met Unity Functions automatically called by the engine .

The chart is as follows ：

Initial stage ：

1、Awake Wake up the ：

      Called immediately when the object is loaded 1 Time ;

      It is often used to initialize before the game starts , It can be judged that when certain conditions are met, execute this script this.enable = true

2、OnEnable When available ： Called whenever the script object is enabled .

3、Start Start ：

      Called when the object is loaded and the script object is enabled 1 Time .

      It is often used to initialize data or game logic , The execution time is later than Awake.

Physical stage ：

1、FixedUpdate Fixed update ： When the script is enabled , Fixed time called , Suitable for physical operation of game objects , For example, mobile, etc . Set update frequency ：“Edit”--> "Project Setting" --> "Time" --> "Fixed Timestep" value , The default is 0.02.

2、OnCollisionXXX Collision ： When the collision conditions are met, call .

3、OnTriggerXXX Trigger ： Call... When the trigger condition is met .

4、OnMouseEnter Mouse migration ： Move the mouse into the current Collider Called when the .

5、OnMouseOver Mouse over ： The mouse passes through the current Collider Called when the .

6、OnMouseExit Mouse away ： The mouse leaves the current Collider Called when the .

7、OnMouseDown The mouse click ： Mouse down the current Collider Called when the .

8、OnMouseUp The mouse is raised ： The mouse is in the current Collider Call... When lifting up .

The game logic ：

1、Update to update ：

        When the script is enabled , Call every time you render a scene , The frequency is related to the performance of the device and the amount of rendering .

2、LateUpdate Delay update ：

        stay Update After the function is called, execute , Suitable for following logic .

Scene rendering ：

1、OnBecameVisible When visible ：

        When Mesh Renderer Called when visible on any camera .

2、OnBecameInvisible When invisible ：

        When Mesh Renderer Called when not visible on any camera .

Closing phase ：

1、OnDisable When not available ：

        This function is called when the object becomes unavailable or the attached game object is inactive .

2、OnDestroy When destroyed ：

        Called when the script is destroyed or the attached game object is destroyed .

3、OnApplicationQuit When the program ends ：

        Called when the application exits .

  The code is as follows ：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
///  Script life cycle / Inevitable events / news Message
/// </summary>
public class Lifecycle : MonoBehaviour
{
    // Script ：.cs Text file for    Class file 
    //      Attach to game objects , Code that defines game object behavior instructions 

    // Serialize fields   effect ： Show private variables in the editor 
    [SerializeField]
    private int a = 100 ;

    // effect ： Hide fields in the editor 
    [HideInInspector]
    public float b;

    [Range(0,100)]
    public int c;

    // attribute ： Cannot display in editor , Usually it is not written in the script 
    public int A
    { 
        get { return this.a; }
        set { this.a = value; }  
    }

    public Lifecycle()
    {
        Debug.Log(" Constructors ");    
        // Don't write constructors in scripts 
        // Cannot access main thread members in child threads 
        //b = Time.time;   
    }

    //*********** Initial stage ****************
    // Execution opportunity ： Create game objects  -->  Execute now 1 Time （ Before start）
    // effect ： initialization 
    private void Awake()
    {
        Debug.Log("Awark-"+Time.time+"-"+this.name);
    }

    // Execution opportunity ： Create game objects  ->  Script enabled  ->  To perform （1 Time ）
    // effect ： initialization 
    private void Start()
    {
        Debug.Log("Start-"+Time.time+"-"+this.name);
    }

    //**************** Physical stage *****************
    // Execution opportunity ： At regular intervals （ Probably 0.02s） perform 1 Time .（ Time can be modified ）
    // Applicability ： Suitable for physical operation of objects （ Move 、 rotate ......）, Not affected by rendering 
    private void FixedUpdate()
    {
        // Rendering time is not fixed （ The amount of rendering per frame is different 、 The performance of the machine is different ）
        //Debug.Log(Time.time);
    }

    private void OnMouseEnter()
    {
        Debug.Log("OnMouseEnter");
    }

    private void OnMouseDown()
    {
        Debug.Log("OnMouseDown");
    }


    //************* The game logic *****************
    // Execution opportunity ： Rendered frame execution , Execution interval is not fixed 
    // Applicability ： Dealing with game logic 
    private void Update()
    {
        // Move forward 1m

        // Check the program execution of a frame 
        // Start debugging  F5  -->   Running scenario   -->   Pause   -->   Add breakpoints to the lines that may go wrong   -->   Single frame operation  -->  debugging ……  -->  Stop debugging  Shift + F5
        int a = 1;
        int b = 2;
        int c = a + b;
    }
}