Merge pull request #1733 from CitiesSkylinesMods/improvement/customiz…

…able-scroll-behavior-closed-dropdown

Custom Dropdown - prevent unwanted option change on mouse wheel scrool

TLM/TLM/State/OptionsTabs/GeneralTab_LocalisationGroup.cs

@@ -10,6 +10,7 @@ namespace TrafficManager.State {
     using TrafficManager.UI;
     using TrafficManager.UI.Helpers;
     using TrafficManager.UI.Textures;
+    using TrafficManager.Util.Extensions;
 
     /// <summary>
     /// Adds localisation options to General options tab.
@@ -64,7 +65,7 @@ public static class GeneralTab_LocalisationGroup {
                 }
             }
 
-            group.AddDropdown(
+            group.AddCustomDropDown(
                 text: T("General.Dropdown:Select language") + ":",
                 options: languageLabels,
                 defaultSelection: languageIndex,
@@ -84,7 +85,7 @@ public static class GeneralTab_LocalisationGroup {
             int selectedThemeIndex = themeNames.FindIndex(x => x == mainConfig.RoadSignTheme);
             int defaultSignsThemeIndex = RoadSignThemeManager.Instance.FindDefaultThemeIndex(mainConfig.DisplaySpeedLimitsMph);
 
-            _roadSignsThemeDropdown = group.AddDropdown(
+            _roadSignsThemeDropdown = group.AddCustomDropDown(
                 text: TSpeedLimits("General.Dropdown:Road signs theme") + ":",
                 options: themeOptions,
                 defaultSelection: selectedThemeIndex >= 0 ? selectedThemeIndex : defaultSignsThemeIndex,

TLM/TLM/TLM.csproj

@@ -184,6 +184,7 @@
     <Compile Include="TrafficLight\Impl\ITrafficLightContainer.cs" />
     <Compile Include="TrafficLight\Impl\TrafficLightSimulation.cs" />
     <Compile Include="UI\AllowDespawn\AllowDespawnPanel.cs" />
+    <Compile Include="UI\Helpers\CustomDownDown.cs" />
     <Compile Include="UI\Helpers\DebugOverlay.cs" />
     <Compile Include="UI\DebugSwitches\DebugSwitchPanel.cs" />
     <Compile Include="UI\DebugSwitches\DebugSwitchCheckboxOption.cs" />

TLM/TLM/UI/Helpers/CustomDownDown.cs

@@ -0,0 +1,36 @@
+namespace TrafficManager.UI.Helpers;
+
+using ColossalFramework.UI;
+using UnityEngine;
+
+/// <summary>
+/// Custom version of vanilla dropdown with customizable mouse wheel behavior on hover closed dropdown control
+/// </summary>
+public class CustomDownDown : UIDropDown {
+    public static GameObject ScrollTemplate;
+
+    /// <summary>
+    /// Use mouse wheel when dropdown is closed to change selection
+    /// Unlike in vanilla, default is False
+    /// </summary>
+    public bool MouseWheelSelectItem { get; set; } = false;
+
+    public override void OnDestroy() {
+        if (ScrollTemplate) {
+            Destroy(ScrollTemplate);
+            ScrollTemplate = null;
+        }
+
+        base.OnDestroy();
+    }
+
+    protected override void OnMouseWheel(UIMouseEventParameter p) {
+        if (MouseWheelSelectItem) {
+            // do default action
+            base.OnMouseWheel(p);
+        } else {
+            // mark as used to prevent scrolling page or selecting different items in the dropdown!
+            p.Use();
+        }
+    }
+}

TLM/TLM/UI/Helpers/DropDownOption.cs

@@ -1,12 +1,12 @@
 namespace TrafficManager.UI.Helpers {
     using ICities;
     using ColossalFramework.UI;
-    using TrafficManager.State;
     using CSUtil.Commons;
     using System;
     using System.Linq;
     using TrafficManager.API.Traffic.Enums;
     using TrafficManager.Util;
+    using TrafficManager.Util.Extensions;
 
     public class DropDownOption<TEnum> : SerializableUIOptionBase<TEnum, UIDropDown, DropDownOption<TEnum>>
         where TEnum : struct, Enum, IConvertible {
@@ -71,7 +71,7 @@ public DropDownOption(string fieldName, Scope scope = Scope.Savegame)
         }
 
         public override DropDownOption<TEnum> AddUI(UIHelperBase container) {
-            _ui = container.AddDropdown(
+            _ui = container.AddCustomDropDown(
                 text: Translate(Label) + ":",
                 options: GetTranslatedItems(),
                 defaultSelection: IndexOf(Value),

TLM/TLM/Util/Extensions/UIHelperExtensions.cs

@@ -1,6 +1,8 @@
 namespace TrafficManager.Util.Extensions {
     using ColossalFramework.UI;
     using ICities;
+    using TrafficManager.Lifecycle;
+    using TrafficManager.UI.Helpers;
     using UnityEngine;
 
     internal static class UIHelperExtensions {
@@ -11,5 +13,99 @@ public static T AddComponent<T>(this UIHelperBase container)
 
         public static T AddUIComponent<T>(this UIHelperBase container)
             where T : UIComponent => container.GetSelf().AddUIComponent<T>();
+
+        public static CustomDownDown AddCustomDropDown(this UIHelperBase container,
+                                                       string text,
+                                                       string[] options,
+                                                       int defaultSelection,
+                                                       OnDropdownSelectionChanged eventCallback
+            ) {
+            if (eventCallback != null && !string.IsNullOrEmpty(text)) {
+                UIComponent root = container.GetSelf();
+                UIPanel uipanel = root.AddUIComponent<UIPanel>();
+                uipanel.area = new Vector4(14, 0, 232, 72);
+                uipanel.autoLayoutDirection = LayoutDirection.Vertical;
+                uipanel.autoLayoutPadding = new RectOffset(1, 0, 2, 0);
+                uipanel.autoLayout = true;
+
+                var label = uipanel.AddUIComponent<UILabel>();
+                label.text = text;
+                label.name = "Label";
+
+                var dropdown = uipanel.AddUIComponent<CustomDownDown>();
+                dropdown.name = "Dropdown";
+                dropdown.area = new Vector4(0, 24, 225, 38);
+                dropdown.items = options;
+                dropdown.selectedIndex = defaultSelection;
+                dropdown.triggerButton = dropdown;
+                dropdown.relativePosition = new Vector3(0, 24, 0);
+                dropdown.itemPadding = new RectOffset(14, 14, 0, 0);
+                dropdown.listPadding = new RectOffset(4, 4, 4, 4);
+                dropdown.textFieldPadding = new RectOffset(14, 40, 7, 4);
+                dropdown.itemHeight = 24;
+                dropdown.listHeight = 200;
+                dropdown.textScale = 1.25f;
+                dropdown.itemHover = "ListItemHover";
+                dropdown.itemHighlight = "ListItemHighlight";
+                dropdown.focusedFgSprite = "OptionsDropboxFocused";
+                dropdown.focusedBgSprite = "OptionsDropboxHovered";
+                dropdown.hoveredBgSprite = "OptionsDropboxHovered";
+                dropdown.normalBgSprite = "OptionsDropbox";
+                dropdown.listBackground = "OptionsDropboxListbox";
+                dropdown.popupColor = Color.white;
+                dropdown.popupTextColor = new Color32(170, 170, 170, 255);
+                dropdown.eventSelectedIndexChanged += delegate(UIComponent c, int sel) {
+                    eventCallback(sel);
+                };
+
+                if (CustomDownDown.ScrollTemplate) {
+                    // reuse gameObject template
+                    dropdown.listScrollbar = CustomDownDown.ScrollTemplate.GetComponent<UIScrollbar>();
+                } else {
+                    UIScrollbar scrollbar = CreateScrollbar();
+                    // cache gameObject for later reuse
+                    CustomDownDown.ScrollTemplate = scrollbar.gameObject;
+                    dropdown.listScrollbar = scrollbar;
+                }
+
+                return dropdown;
+            }
+            return null;
+        }
+
+        private static UIScrollbar CreateScrollbar() {
+            UIScrollbar verticalScrollbar = new GameObject("TMPE_ScrollbarV").AddComponent<UIScrollbar>();
+            // attach to lifecycle gameObject for easier search in gameObject tree
+            verticalScrollbar.gameObject.transform.SetParent(TMPELifecycle.Instance.gameObject.transform);
+
+            verticalScrollbar.name = "TMPE_ScrollbarV";
+            verticalScrollbar.width = 25;
+            verticalScrollbar.height = 200;
+            verticalScrollbar.orientation = UIOrientation.Vertical;
+            verticalScrollbar.pivot = UIPivotPoint.TopLeft;
+            verticalScrollbar.minValue = 0;
+            verticalScrollbar.maxValue = 87;
+            verticalScrollbar.value = 0;
+            verticalScrollbar.incrementAmount = 50;
+            verticalScrollbar.autoHide = true;
+
+            UISlicedSprite trackSprite = verticalScrollbar.AddUIComponent<UISlicedSprite>();
+            trackSprite.relativePosition = Vector2.zero;
+            trackSprite.autoSize = true;
+            trackSprite.size = trackSprite.parent.size;
+            trackSprite.fillDirection = UIFillDirection.Vertical;
+            trackSprite.spriteName = "ScrollbarTrack";
+            verticalScrollbar.trackObject = trackSprite;
+
+            UISlicedSprite thumbSprite = trackSprite.AddUIComponent<UISlicedSprite>();
+            thumbSprite.relativePosition = Vector2.zero;
+            thumbSprite.fillDirection = UIFillDirection.Vertical;
+            thumbSprite.autoSize = true;
+            thumbSprite.width = thumbSprite.parent.width - 6;
+            thumbSprite.spriteName = "ScrollbarThumb";
+            verticalScrollbar.thumbObject = thumbSprite;
+
+            return verticalScrollbar;
+        }
     }
 }

TLM/TLM/Util/Shortcuts.cs

@@ -146,7 +146,7 @@ internal static class Shortcuts {
         /// <exception cref="ArgumentException">
         /// Thrown if <typeparamref name="T"/> is not some kind of <see cref="Enum"/>.
         /// </exception>
-        internal static void AssertNotNone<T>(T value, string m = "") where T: IEquatable<T> {
+        internal static void AssertNotNone<T>(T value, string m = "") where T: Enum {
             if (!typeof(T).IsEnum)
                 throw new ArgumentException($"Type '{typeof(T).FullName}' is not an enum");