///Credit perchik ///Sourced from - http://forum.unity3d.com/threads/receive-onclick-event-and-pass-it-on-to-lower-ui-elements.293642/ using System.Collections.Generic; namespace UnityEngine.UI.Extensions { /// /// Extension to the UI class which creates a dropdown list /// [RequireComponent(typeof(RectTransform))] [AddComponentMenu("UI/Extensions/Dropdown List")] public class DropDownList : MonoBehaviour { public Color disabledTextColor; public DropDownListItem SelectedItem { get; private set; } //outside world gets to get this, not set it public List Items; public System.Action OnSelectionChanged; // fires when selection is changed; public bool OverrideHighlighted = true; //private bool isInitialized = false; private bool _isPanelActive = false; private bool _hasDrawnOnce = false; private DropDownListButton _mainButton; private RectTransform _rectTransform; private RectTransform _overlayRT; private RectTransform _scrollPanelRT; private RectTransform _scrollBarRT; private RectTransform _slidingAreaRT; // private RectTransform scrollHandleRT; private RectTransform _itemsPanelRT; private Canvas _canvas; private RectTransform _canvasRT; private ScrollRect _scrollRect; private List _panelItems; private GameObject _itemTemplate; [SerializeField] private float _scrollBarWidth = 20.0f; public float ScrollBarWidth { get { return _scrollBarWidth; } set { _scrollBarWidth = value; RedrawPanel(); } } // private int scrollOffset; //offset of the selected item private int _selectedIndex = 0; [SerializeField] private int _itemsToDisplay; public int ItemsToDisplay { get { return _itemsToDisplay; } set { _itemsToDisplay = value; RedrawPanel(); } } public bool interactible { get { return _mainButton.btn.interactable; } private set { _mainButton.btn.interactable = value; if (!value && _isPanelActive) { ToggleDropdownPanel (false); } } } [SerializeField] //I couldn't come up with a better name private bool _technicallyInteractible = true; public bool TechnicallyInteractible { get { return _technicallyInteractible; } set { _technicallyInteractible = value; interactible = _technicallyInteractible && (Items.Count > 0 || _remainInteractableIfEmpty); } } [SerializeField] private bool _remainInteractableIfEmpty = true; public bool RemainInteractableIfEmpty { get { return _remainInteractableIfEmpty; } set { _remainInteractableIfEmpty = value; interactible = _technicallyInteractible && (Items.Count > 0 || _remainInteractableIfEmpty); } } public bool SelectFirstItemOnStart = false; public void Start() { Initialize(); if (SelectFirstItemOnStart && Items.Count > 0) { ToggleDropdownPanel (false); OnItemClicked (0); } } private bool Initialize() { bool success = true; try { _rectTransform = GetComponent(); _mainButton = new DropDownListButton(_rectTransform.FindChild("MainButton").gameObject); _overlayRT = _rectTransform.FindChild("Overlay").GetComponent(); _overlayRT.gameObject.SetActive(false); _scrollPanelRT = _overlayRT.FindChild("ScrollPanel").GetComponent(); _scrollBarRT = _scrollPanelRT.FindChild("Scrollbar").GetComponent(); _slidingAreaRT = _scrollBarRT.FindChild("SlidingArea").GetComponent(); // scrollHandleRT = slidingAreaRT.FindChild("Handle").GetComponent(); _itemsPanelRT = _scrollPanelRT.FindChild("Items").GetComponent(); //itemPanelLayout = itemsPanelRT.gameObject.GetComponent(); _canvas = GetComponentInParent(); _canvasRT = _canvas.GetComponent(); _scrollRect = _scrollPanelRT.GetComponent(); _scrollRect.scrollSensitivity = _rectTransform.sizeDelta.y / 2; _scrollRect.movementType = ScrollRect.MovementType.Clamped; _scrollRect.content = _itemsPanelRT; _itemTemplate = _rectTransform.FindChild("ItemTemplate").gameObject; _itemTemplate.SetActive(false); } catch (System.NullReferenceException ex) { Debug.LogException(ex); Debug.LogError("Something is setup incorrectly with the dropdownlist component causing a Null Reference Exception"); success = false; } _panelItems = new List(); RebuildPanel(); RedrawPanel(); return success; } /* currently just using items in the list instead of being able to add to it. public void AddItems(params object[] list) { List ddItems = new List(); foreach (var obj in list) { if (obj is DropDownListItem) { ddItems.Add((DropDownListItem)obj); } else if (obj is string) { ddItems.Add(new DropDownListItem(caption: (string)obj)); } else if (obj is Sprite) { ddItems.Add(new DropDownListItem(image: (Sprite)obj)); } else { throw new System.Exception("Only ComboBoxItems, Strings, and Sprite types are allowed"); } } Items.AddRange(ddItems); Items = Items.Distinct().ToList();//remove any duplicates RebuildPanel(); } */ /// /// Rebuilds the contents of the panel in response to items being added. /// private void RebuildPanel() { if (Items.Count == 0) return; int indx = _panelItems.Count; while (_panelItems.Count < Items.Count) { GameObject newItem = Instantiate(_itemTemplate) as GameObject; newItem.name = "Item " + indx; newItem.transform.SetParent(_itemsPanelRT, false); _panelItems.Add(new DropDownListButton(newItem)); indx++; } for (int i = 0; i < _panelItems.Count; i++) { if (i < Items.Count) { DropDownListItem item = Items[i]; _panelItems[i].txt.text = item.Caption; if (item.IsDisabled) _panelItems[i].txt.color = disabledTextColor; if (_panelItems[i].btnImg != null) _panelItems[i].btnImg.sprite = null;//hide the button image _panelItems[i].img.sprite = item.Image; _panelItems[i].img.color = (item.Image == null) ? new Color(1, 1, 1, 0) : item.IsDisabled ? new Color(1, 1, 1, .5f) : Color.white; int ii = i; //have to copy the variable for use in anonymous function _panelItems[i].btn.onClick.RemoveAllListeners(); _panelItems[i].btn.onClick.AddListener(() => { OnItemClicked(ii); if (item.OnSelect != null) item.OnSelect(); }); } _panelItems[i].gameobject.SetActive(i < Items.Count);// if we have more thanks in the panel than Items in the list hide them } interactible = _technicallyInteractible && (Items.Count > 0 || _remainInteractableIfEmpty); } private void OnItemClicked(int indx) { Debug.Log("item " + indx + " clicked"); if (indx != _selectedIndex && OnSelectionChanged != null) OnSelectionChanged(indx); _selectedIndex = indx; ToggleDropdownPanel(true); UpdateSelected(); } private void UpdateSelected() { SelectedItem = (_selectedIndex > -1 && _selectedIndex < Items.Count) ? Items[_selectedIndex] : null; if (SelectedItem == null) return; bool hasImage = SelectedItem.Image != null; if (hasImage) { _mainButton.img.sprite = SelectedItem.Image; _mainButton.img.color = Color.white; //if (Interactable) mainButton.img.color = Color.white; //else mainButton.img.color = new Color(1, 1, 1, .5f); } else { _mainButton.img.sprite = null; } _mainButton.txt.text = SelectedItem.Caption; //update selected index color if (OverrideHighlighted) { for (int i = 0; i < _itemsPanelRT.childCount; i++) { _panelItems[i].btnImg.color = (_selectedIndex == i) ? _mainButton.btn.colors.highlightedColor : new Color(0, 0, 0, 0); } } } private void RedrawPanel() { float scrollbarWidth = Items.Count > ItemsToDisplay ? _scrollBarWidth : 0f;//hide the scrollbar if there's not enough items if (!_hasDrawnOnce || _rectTransform.sizeDelta != _mainButton.rectTransform.sizeDelta) { _hasDrawnOnce = true; _mainButton.rectTransform.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, _rectTransform.sizeDelta.x); _mainButton.rectTransform.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, _rectTransform.sizeDelta.y); _mainButton.txt.rectTransform.offsetMax = new Vector2(4, 0); _scrollPanelRT.SetParent(transform, true);//break the scroll panel from the overlay _scrollPanelRT.anchoredPosition = new Vector2(0, -_rectTransform.sizeDelta.y); //anchor it to the bottom of the button //make the overlay fill the screen _overlayRT.SetParent(_canvas.transform, false); //attach it to top level object _overlayRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, _canvasRT.sizeDelta.x); _overlayRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, _canvasRT.sizeDelta.y); _overlayRT.SetParent(transform, true);//reattach to this object _scrollPanelRT.SetParent(_overlayRT, true); //reattach the scrollpanel to the overlay } if (Items.Count < 1) return; float dropdownHeight = _rectTransform.sizeDelta.y * Mathf.Min(_itemsToDisplay, Items.Count); _scrollPanelRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, dropdownHeight); _scrollPanelRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, _rectTransform.sizeDelta.x); _itemsPanelRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, _scrollPanelRT.sizeDelta.x - scrollbarWidth - 5); _itemsPanelRT.anchoredPosition = new Vector2(5, 0); _scrollBarRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, scrollbarWidth); _scrollBarRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, dropdownHeight); _slidingAreaRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, 0); _slidingAreaRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, dropdownHeight - _scrollBarRT.sizeDelta.x); } /// /// Toggle the drop down list /// /// whether an item was directly clicked on public void ToggleDropdownPanel(bool directClick) { _overlayRT.transform.localScale = new Vector3(1, 1, 1); _scrollBarRT.transform.localScale = new Vector3(1, 1, 1); _isPanelActive = !_isPanelActive; _overlayRT.gameObject.SetActive(_isPanelActive); if (_isPanelActive) { transform.SetAsLastSibling(); } else if (directClick) { // scrollOffset = Mathf.RoundToInt(itemsPanelRT.anchoredPosition.y / _rectTransform.sizeDelta.y); } } } }