Unity UGUI 之实现按钮 Button 长按和双击的功能效果

一、简单介绍

二、实现原理

三、注意事项

四、效果预览

五、实现步骤

六、关键代码

七、自己完全重写 Button (面板有 onClick, onLongPress, onDoubleClick 事件添加)

一、简单介绍

UGUI，是Unity自带的 GUI 系统，有别于 NGUI；使用 UGUI 也能制作出比较酷炫的效果。

本节简单介绍实现 UGUI 按钮的长按功能，以及Double Click 的功能。

二、实现原理

1、继承原有的UGUI 的 Button，组件

2、在 Button 的上面实现长按和双击事件

三、注意事项

1、长按和双击事件实现和原有的单击事件方法类似（目前不能显示的面板中，估计还有注意什么，知道的朋友可以留言啊（可能是继承 Button 子类已经有 UnityEvent (还是奇怪)），后面脚本有完全重写的Button 中面板有 onClick, onLongPress, onDoubleClick 事件）

2、触发双击的时候，可能总是会触发一次单击事件，顺序是先触发单击事件，之后双击事件触发（尝试了一些方法暂时没有方法在取消双击前的单击，知道的朋友留言哈）

四、效果预览

五、实现步骤

1、打开Unity，新建空工程

2、在场景中，简单布局场景，方便测试

3、新建脚本 MuButton，继承 Button，代码实现长按和双击效果的逻辑，并添加一个测试脚本，测试 MyButton 效果

4、移除Button 上的Button组件，添加 MyButton

5、添加测试脚本 TestMyButton

6、运行场景，测试效果如上

六、关键代码

1、MyButton.cs

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;/// <summary>
/// 我的自定义Button，继承 Button
/// </summary>
public class MyButton : Button
{// 构造函数protected MyButton(){my_onDoubleClick = new ButtonClickedEvent();my_onLongPress = new ButtonClickedEvent();}// 长按public ButtonClickedEvent my_onLongPress;public ButtonClickedEvent OnLongPress{get { return my_onLongPress; }set { my_onLongPress = value; }}// 双击public ButtonClickedEvent my_onDoubleClick;public ButtonClickedEvent OnDoubleClick{get { return my_onDoubleClick; }set { my_onDoubleClick = value; }}// 长按需要的变量参数private bool my_isStartPress = false;private float my_curPointDownTime = 0f;private float my_longPressTime = 0.6f;private bool my_longPressTrigger = false;void Update(){CheckIsLongPress();}#region 长按/// <summary>/// 处理长按/// </summary>void CheckIsLongPress() {if (my_isStartPress && !my_longPressTrigger){if (Time.time > my_curPointDownTime + my_longPressTime){my_longPressTrigger = true;my_isStartPress = false;if (my_onLongPress != null){my_onLongPress.Invoke();}}}}public override void OnPointerDown(PointerEventData eventData){// 按下刷新當前時間base.OnPointerDown(eventData);my_curPointDownTime = Time.time;my_isStartPress = true;my_longPressTrigger = false;}public override void OnPointerUp(PointerEventData eventData){// 指針擡起，結束開始長按base.OnPointerUp(eventData);my_isStartPress = false;}public override void OnPointerExit(PointerEventData eventData){// 指針移出，結束開始長按，計時長按標志base.OnPointerExit(eventData);my_isStartPress = false;}#endregion#region 双击（单击）public override void OnPointerClick(PointerEventData eventData){//(避免已經點擊進入長按后，擡起的情況)if (!my_longPressTrigger){// 正常單擊 if (eventData.clickCount == 2 ){if (my_onDoubleClick != null){my_onDoubleClick.Invoke();}}// 雙擊else if (eventData.clickCount == 1){onClick.Invoke();}}}#endregion}

2、TestMyButton.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class TestMyButton : MonoBehaviour
{public MyButton myButton;// Start is called before the first frame updatevoid Start(){myButton.onClick.AddListener(()=> {Debug.Log(" myButton.onClick");});myButton.OnDoubleClick.AddListener(() => {Debug.Log(" myButton.OnDoubleClick");});myButton.OnLongPress.AddListener(() => {Debug.Log(" myButton.OnLongPress");});}// Update is called once per framevoid Update(){}
}

七、自己完全重写 Button (面板有 onClick, onLongPress, onDoubleClick 事件添加)

（注意：使用方法原有的Button一样）

1、样式

2、代码

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine.EventSystems;
using UnityEngine.Events;
using UnityEngine.UI;
using UnityEngine.Serialization;
using UnityEngine;namespace XANTools
{/// <summary>/// 自己重写的 Button 按钮/// 1、单击/// 2、双击/// 3、长按/// </summary>    public class MyButtonXAN : Selectable, IPointerClickHandler, ISubmitHandler{[Serializable]/// <summary>/// Function definition for a button click event./// </summary>public class ButtonClickedEvent : UnityEvent { }// Event delegates triggered on click.[FormerlySerializedAs("onClick")][SerializeField]private ButtonClickedEvent m_OnClick = new ButtonClickedEvent();protected MyButtonXAN(){ }public ButtonClickedEvent onClick{get { return m_OnClick; }set { m_OnClick = value; }}private void Press(){if (!IsActive() || !IsInteractable())return;UISystemProfilerApi.AddMarker("Button.onClick", this);m_OnClick.Invoke();}[Serializable]/// <summary>/// Function definition for a button click event./// </summary>public class ButtonLongPressEvent : UnityEvent { }[FormerlySerializedAs("onLongPress")][SerializeField]private ButtonLongPressEvent m_onLongPress = new ButtonLongPressEvent();public ButtonLongPressEvent onLongPress{get { return m_onLongPress; }set { m_onLongPress = value; }}[FormerlySerializedAs("OnDoubleClick")]public ButtonClickedEvent m_onDoubleClick = new ButtonClickedEvent();public ButtonClickedEvent OnDoubleClick{get { return m_onDoubleClick; }set { m_onDoubleClick = value; }}private bool my_isStartPress = false;private float my_curPointDownTime = 0f;private float my_longPressTime = 0.6f;private bool my_longPressTrigger = false;void Update(){CheckIsLongPress();}void CheckIsLongPress(){if (my_isStartPress && !my_longPressTrigger){if (Time.time > my_curPointDownTime + my_longPressTime){my_longPressTrigger = true;my_isStartPress = false;if (m_onLongPress != null){m_onLongPress.Invoke();}}}}public virtual void OnPointerClick(PointerEventData eventData){//(避免已經點擊進入長按后，擡起的情況)if (!my_longPressTrigger){// 正常單擊 if (eventData.clickCount == 2){if (m_onDoubleClick != null){m_onDoubleClick.Invoke();}}// 雙擊else if (eventData.clickCount == 1){onClick.Invoke();}}}public virtual void OnSubmit(BaseEventData eventData){Press();// if we get set disabled during the press// don't run the coroutine.if (!IsActive() || !IsInteractable())return;DoStateTransition(SelectionState.Pressed, false);StartCoroutine(OnFinishSubmit());}private IEnumerator OnFinishSubmit(){var fadeTime = colors.fadeDuration;var elapsedTime = 0f;while (elapsedTime < fadeTime){elapsedTime += Time.unscaledDeltaTime;yield return null;}DoStateTransition(currentSelectionState, false);}public override void OnPointerDown(PointerEventData eventData){// 按下刷新當前時間base.OnPointerDown(eventData);my_curPointDownTime = Time.time;my_isStartPress = true;my_longPressTrigger = false;}public override void OnPointerUp(PointerEventData eventData){// 指針擡起，結束開始長按base.OnPointerUp(eventData);my_isStartPress = false;}public override void OnPointerExit(PointerEventData eventData){// 指針移出，結束開始長按，計時長按標志base.OnPointerExit(eventData);my_isStartPress = false;}}
}