com.unity.uiextensions/Runtime/Scripts/Controls/ComboBox/DropDownList.cs

444 lines
14 KiB
C#

///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
{
/// <summary>
/// Extension to the UI class which creates a dropdown list
/// </summary>
[RequireComponent(typeof(RectTransform))]
[AddComponentMenu("UI/Extensions/ComboBox/Dropdown List")]
public class DropDownList : MonoBehaviour
{
public Color disabledTextColor;
public DropDownListItem SelectedItem { get; private set; } //outside world gets to get this, not set it
[Header("Dropdown List Items")]
public List<DropDownListItem> Items;
[Header("Properties")]
[SerializeField]
private bool isActive = true;
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<DropDownListButton> _panelItems = new List<DropDownListButton>();
private GameObject _itemTemplate;
private bool _initialized;
[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 = -1;
[SerializeField]
private int _itemsToDisplay;
public int ItemsToDisplay
{
get { return _itemsToDisplay; }
set
{
_itemsToDisplay = value;
RedrawPanel();
}
}
[SerializeField]
private float dropdownOffset;
[SerializeField]
private bool _displayPanelAbove = false;
public bool SelectFirstItemOnStart = false;
[SerializeField]
private int selectItemIndexOnStart = 0;
private bool shouldSelectItemOnStart => SelectFirstItemOnStart || selectItemIndexOnStart > 0;
[System.Serializable]
public class SelectionChangedEvent : Events.UnityEvent<int> { }
// fires when item is changed;
[Header("Events")]
public SelectionChangedEvent OnSelectionChanged;
[System.Serializable]
public class ControlDisabledEvent : Events.UnityEvent<bool> { }
// fires when item is changed;
public ControlDisabledEvent OnControlDisabled;
public void Start()
{
Initialize();
if (shouldSelectItemOnStart && Items.Count > 0)
{
SelectItemIndex(SelectFirstItemOnStart ? 0 : selectItemIndexOnStart);
}
RedrawPanel();
}
private bool Initialize()
{
if (_initialized) return true;
bool success = true;
try
{
_rectTransform = GetComponent<RectTransform>();
_mainButton = new DropDownListButton(_rectTransform.Find("MainButton").gameObject);
_overlayRT = _rectTransform.Find("Overlay").GetComponent<RectTransform>();
_overlayRT.gameObject.SetActive(false);
_scrollPanelRT = _overlayRT.Find("ScrollPanel").GetComponent<RectTransform>();
_scrollBarRT = _scrollPanelRT.Find("Scrollbar").GetComponent<RectTransform>();
_slidingAreaRT = _scrollBarRT.Find("SlidingArea").GetComponent<RectTransform>();
_scrollHandleRT = _slidingAreaRT.Find("Handle").GetComponent<RectTransform>();
_itemsPanelRT = _scrollPanelRT.Find("Items").GetComponent<RectTransform>();
//itemPanelLayout = itemsPanelRT.gameObject.GetComponent<LayoutGroup>();
_canvas = GetComponentInParent<Canvas>();
_canvasRT = _canvas.GetComponent<RectTransform>();
_scrollRect = _scrollPanelRT.GetComponent<ScrollRect>();
_scrollRect.scrollSensitivity = _rectTransform.sizeDelta.y / 2;
_scrollRect.movementType = ScrollRect.MovementType.Clamped;
_scrollRect.content = _itemsPanelRT;
_itemTemplate = _rectTransform.Find("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;
}
_initialized = true;
RebuildPanel();
RedrawPanel();
return success;
}
/// <summary>
/// Update the drop down selection to a specific index
/// </summary>
/// <param name="index"></param>
public void SelectItemIndex(int index)
{
ToggleDropdownPanel(false);
OnItemClicked(index);
}
// currently just using items in the list instead of being able to add to it.
/// <summary>
/// Rebuilds the list from a new collection.
/// </summary>
/// <remarks>
/// NOTE, this will clear all existing items
/// </remarks>
/// <param name="list"></param>
public void RefreshItems(params object[] list)
{
Items.Clear();
List<DropDownListItem> ddItems = new List<DropDownListItem>();
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);
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Adds an additional item to the drop down list (recommended)
/// </summary>
/// <param name="item">Item of type DropDownListItem</param>
public void AddItem(DropDownListItem item)
{
Items.Add(item);
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Adds an additional drop down list item using a string name
/// </summary>
/// <param name="item">Item of type String</param>
public void AddItem(string item)
{
Items.Add(new DropDownListItem(caption: (string)item));
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Adds an additional drop down list item using a sprite image
/// </summary>
/// <param name="item">Item of type UI Sprite</param>
public void AddItem(Sprite item)
{
Items.Add(new DropDownListItem(image: (Sprite)item));
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Removes an item from the drop down list (recommended)
/// </summary>
/// <param name="item">Item of type DropDownListItem</param>
public void RemoveItem(DropDownListItem item)
{
Items.Remove(item);
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Removes an item from the drop down list item using a string name
/// </summary>
/// <param name="item">Item of type String</param>
public void RemoveItem(string item)
{
Items.Remove(new DropDownListItem(caption: (string)item));
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Removes an item from the drop down list item using a sprite image
/// </summary>
/// <param name="item">Item of type UI Sprite</param>
public void RemoveItem(Sprite item)
{
Items.Remove(new DropDownListItem(image: (Sprite)item));
RebuildPanel();
RedrawPanel();
}
public void ResetItems()
{
Items.Clear();
RebuildPanel();
RedrawPanel();
}
/// <summary>
/// Rebuilds the contents of the panel in response to items being added.
/// </summary>
private void RebuildPanel()
{
if (Items.Count == 0) return;
if (!_initialized)
{
Start();
}
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
}
}
private void OnItemClicked(int indx)
{
//Debug.Log("item " + indx + " clicked");
if (indx != _selectedIndex && OnSelectionChanged != null) OnSelectionChanged.Invoke(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;
}
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 = _panelItems.Count > ItemsToDisplay ? _scrollBarWidth : 0f;//hide the scrollbar if there's not enough items
_scrollBarRT.gameObject.SetActive(_panelItems.Count > ItemsToDisplay);
float dropdownHeight = _itemsToDisplay > 0 ? _rectTransform.sizeDelta.y * Mathf.Min(_itemsToDisplay, _panelItems.Count) : _rectTransform.sizeDelta.y * _panelItems.Count;
dropdownHeight += dropdownOffset;
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);
var itemsRemaining = _panelItems.Count - ItemsToDisplay;
itemsRemaining = itemsRemaining < 0 ? 0 : itemsRemaining;
_scrollPanelRT.SetParent(transform, true);
_scrollPanelRT.anchoredPosition = _displayPanelAbove ?
new Vector2(0, dropdownOffset + dropdownHeight) :
new Vector2(0, -(dropdownOffset + _rectTransform.sizeDelta.y));
//make the overlay fill the screen
_overlayRT.SetParent(_canvas.transform, false);
_overlayRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, _canvasRT.sizeDelta.x);
_overlayRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, _canvasRT.sizeDelta.y);
_overlayRT.SetParent(transform, true);
_scrollPanelRT.SetParent(_overlayRT, true);
}
if (_panelItems.Count < 1) return;
_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);
if (scrollbarWidth == 0) _scrollHandleRT.gameObject.SetActive(false); else _scrollHandleRT.gameObject.SetActive(true);
_slidingAreaRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Horizontal, 0);
_slidingAreaRT.SetSizeWithCurrentAnchors(RectTransform.Axis.Vertical, dropdownHeight - _scrollBarRT.sizeDelta.x);
}
/// <summary>
/// Toggle the drop down list
/// </summary>
/// <param name="directClick"> whether an item was directly clicked on</param>
public void ToggleDropdownPanel(bool directClick)
{
if (!isActive) return;
_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);
}
}
/// <summary>
/// Updates the control and sets its active status, determines whether the dropdown will open ot not
/// </summary>
/// <param name="status"></param>
public void SetActive(bool status)
{
if (status != isActive)
{
OnControlDisabled?.Invoke(status);
}
isActive = status;
}
}
}