[Unity Case] Double click and long press of Button

Implementation content:

Extend Unity's own Button component to achieve double-click and long-press effects based on the original click event;

Replace the Button component and select which event is currently executed through the radio button

Detailed code explanation:

1. Click event handling:
   • Control whether to enable click events throughsingleClickEnabled switch.
   • InOnPointerClick method, execute the click event according to the activation state and interactable state of the button.
   • Use Unity's Profiler API to add markers and trigger the button's click event callback.
2. Double-click event handling:
   • Control whether to enable double-click events throughdoubleClickEnabled switch.
   • InOnPointerClick method, record the number of clicks and determine whether to trigger a double-click event based on the double-click time threshold.
   • If a double-click is detected, add a Profiler tag, trigger the double-click event callback, and reset the click count.
3. Long press event handling:
   • Control whether to enable long press events throughlongPressEnabled switch.
   • InOnPointerDown method, record the press time and mark the long press state.
   • InOnPointerUp method, reset the long press state.
   • UseUpdate method to detect long press regularly. If the long press time threshold is reached, the long press event callback is triggered.
4. Event callback:
   • Use ButtonClickedEvent type of event callback, which can be configured in the Inspector.
   • Provides event callbacks for click, double-click and long press, which can be set through the Inspector or code.

The complete code is as follows:

using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.Serialization;
using UnityEngine.UI;

public class ButtonExtension : Button
{
    #region 单机双击相关

    public bool singleClickEnabled = true;
    public bool doubleClickEnabled = false;
    public float doubleClickTime = 0.3f;
    
    private float lastClickTime = float.NegativeInfinity;
    private int clickCount = 0;
    
    [FormerlySerializedAs("onDoubleClick")]
    [SerializeField]
    private ButtonClickedEvent doubleClickEvent = new ();
    
    public ButtonClickedEvent onDoubleClick
    {
        get => doubleClickEvent;
        set => doubleClickEvent = value;
    }

    public override void OnPointerClick(PointerEventData eventData)
    {
        if(!IsActive() && !interactable) 
            return;

        if (singleClickEnabled)
        {
            UISystemProfilerApi.AddMarker("Button.onClick", this);
            onClick?.Invoke();
            Debug.LogError("单击");   
        }

        if (doubleClickEnabled)
        {
            clickCount++;
            if (clickCount >= 2)
            {
                if (Time.realtimeSinceStartup - lastClickTime < doubleClickTime)
                {
                    UISystemProfilerApi.AddMarker("Button.onDoubleClick", this);
                    onDoubleClick?.Invoke();
                    Debug.LogError("双击");
                    lastClickTime = float.NegativeInfinity;
                    clickCount = 0;   
                }
                else
                {
                    clickCount = 1;
                    lastClickTime = Time.unscaledTime;
                }
            }
            else
            {
                lastClickTime = Time.unscaledTime;
            }
        }
    }

    #endregion

    #region 长按相关

    public bool longPressEnabled = false;

    private float lastPressTime = 0;
    
    public float minPressTime = 0.5f;

    private bool isPressing = false;
    
    private bool hasInvokedLongPress = false;

    [FormerlySerializedAs("onLongPress")]
    [SerializeField]
    private ButtonClickedEvent longPressEvent = new();
    
    public ButtonClickedEvent onLongPress
    {
        get => longPressEvent;
        set => longPressEvent = value;
    }
    
    public override void OnPointerDown(PointerEventData eventData)
    {
        base.OnPointerDown(eventData);
        if (longPressEnabled)
        {
            hasInvokedLongPress = false;
            isPressing = true;
            lastPressTime = Time.unscaledTime;   
        }
    }

    public override void OnPointerUp(PointerEventData eventData)
    {
        base.OnPointerUp(eventData);
        isPressing = false;
        hasInvokedLongPress = false;
    }

    private void Update()
    {
        DealLongPress();
    }
    
    private void DealLongPress()
    {
        if(hasInvokedLongPress) return;
        if (isPressing)
        {
            if (Time.unscaledTime - lastPressTime >= minPressTime)
            {
                UISystemProfilerApi.AddMarker("Button.onLongPress", this);
                onLongPress?.Invoke();
                hasInvokedLongPress = true;
                Debug.LogError("执行长按事件");
            }
        }
    }

    #endregion
}

Add the new properties to the Inspector panel, the specific code is as follows:

using UnityEngine;

namespace UnityEditor.UI
{
    [CustomEditor(typeof(ButtonExtension), true)]
    [CanEditMultipleObjects]
    public class ButtonExInspector : SelectableEditor
    {
        private ButtonExtension buttonExtension;

        SerializedProperty onDoubleClickProperty;
        SerializedProperty onClickProperty;
        SerializedProperty onLongPressProperty;
        
        protected override void OnEnable()
        {
            base.OnEnable();
            onDoubleClickProperty = serializedObject.FindProperty("doubleClickEvent");
            onClickProperty = serializedObject.FindProperty("m_OnClick");
            onLongPressProperty = serializedObject.FindProperty("longPressEvent");
        }

        public override void OnInspectorGUI()
        {
            base.OnInspectorGUI();
            serializedObject.Update();
            buttonExtension = (ButtonExtension)target;
            EditorGUILayout.Space();

            buttonExtension.singleClickEnabled = EditorGUILayout.Toggle("启用单击", buttonExtension.singleClickEnabled);
            if (buttonExtension.singleClickEnabled)
            {
                buttonExtension.doubleClickEnabled = false;
                buttonExtension.longPressEnabled = false;
                EditorGUILayout.PropertyField(onClickProperty);  
            }
            
            buttonExtension.doubleClickEnabled = EditorGUILayout.Toggle("启用双击", buttonExtension.doubleClickEnabled);
            if (buttonExtension.doubleClickEnabled)
            {
                buttonExtension.doubleClickTime = EditorGUILayout.FloatField("双击间隔", buttonExtension.doubleClickTime);
                buttonExtension.singleClickEnabled = false;
                buttonExtension.longPressEnabled = false;
                EditorGUILayout.PropertyField(onDoubleClickProperty);
            }
            
            buttonExtension.longPressEnabled = EditorGUILayout.Toggle("启用长按", buttonExtension.longPressEnabled);
            if(buttonExtension.longPressEnabled)
            {
                buttonExtension.minPressTime = EditorGUILayout.FloatField("长按时间", buttonExtension.minPressTime);
                buttonExtension.singleClickEnabled = false;
                buttonExtension.doubleClickEnabled = false;
                EditorGUILayout.PropertyField(onLongPressProperty);
            }
            
            serializedObject.ApplyModifiedProperties();
            if(GUI.changed)
                EditorUtility.SetDirty(target);
        }
    }   
}