Unity3d-在另一个脚本中定义事件

问题描述：

假设我想向下拉元素的OnSelect()事件添加功能.

Let's say I would like to add functionality to the OnSelect() Event of a dropdown element.

通常我只是将新脚本添加到特定的下拉gameObject中:

Normally I would just add a new script to the specific dropdown gameObject:

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class LanguageDropdown : MonoBehaviour, ISelectHandler// required interface when using the OnSelect method.
{
    //Do this when the selectable UI object is selected.
    public void OnSelect(BaseEventData eventData)
    {
        Debug.Log(this.gameObject.name + " was selected");
    }
}

提示:如果选择了下拉菜单，脚本只会输出一条消息.

Hint: The script simply outputs a message if the Dropdown is getting selected.

问题:是否可以在另一个脚本中定义功能? 例如.我有一个脚本附加到主父菜单"Menue"，在其中引用此特定的下拉游戏对象.

Question: Is it possible to define the functionality inside another script? E.g. I have a script attached to the master parent "Menue" where I am referencing this specific dropdown gameobject.

如何在另一个脚本中定义OnSelect?

How can I define the OnSelect inside another script?

PS:这是问这个问题的正确地方，还是我应该在游戏开发上问这个问题?

PS: Is this the correct place to ask this question, or should I ask it on gamedevelopement instead?

答

使用事件和委托.如果您是新手，可以在此处中找到简化的教程.

Use event and delegate. You can find a simplified tutorial for that here if this is new to you.

应该是这样的:

public delegate void SelectAction(GameObject target);
public static event SelectAction OnSelectedEvent;

将其添加到您的LanguageDropdown脚本中，您应该得到以下信息:

Add that to your LanguageDropdown script and you should get this:

public class LanguageDropdown : MonoBehaviour, ISelectHandler// required interface when using the OnSelect method.
{
    public delegate void SelectAction(GameObject target);
    public static event SelectAction OnSelectedEvent;

    //Do this when the selectable UI object is selected.
    public void OnSelect(BaseEventData eventData)
    {
        Debug.Log(this.gameObject.name + " was selected");

        //Invoke Event
        if (OnSelectedEvent != null)
        {
            OnSelectedEvent(this.gameObject);
        }
    }
}

现在，您可以分别从另一个脚本的OnEnable和OnDisable函数脚本中订阅和取消订阅该事件:

Now, you can subscribe and un-subscribe to the event in the OnEnable and OnDisable functions respectively script from another script:

void OnEnable()
{
    //subscribe to event
    LanguageDropdown.OnSelectedEvent += SelectAction;
}

void OnDisable()
{
    //Un-subscribe to event
    LanguageDropdown.OnSelectedEvent -= SelectAction;
}

//This will be called when invoked
void SelectAction(GameObject target)
{
    Debug.Log(target.name + " was selected");
}

基本上我想知道是否被迫附加了脚本 LanguageDropdown到游戏对象，或者如果不需要，我可以通过未附加到该脚本的另一个脚本来设置所有内容具体下拉菜单.

Basically I wanted to know if I am forced to attach the script LanguageDropdown to the gameobject, or If this is not required and I can setup everything from another script which is not attached to that specific dropdown.

否，您可以使用EventTrigger类注册如下所示的事件，而不必将其附加到每个对象上:

No, you can use the EventTrigger class to register the events like below and you won't have to attach it to each object:

EventTrigger.Entry entry = new EventTrigger.Entry();
entry.eventID = EventTriggerType.Select;
entry.callback.AddListener((eventData) => { SelectAction(); });

请不要使用它.速度很慢，我也已从多人处验证了这一点.

Please, do not use that. It is slow and I have verified this from multiple people too.

Unity3d-在另一个脚本中定义事件

相关推荐