feat(UI): Add dropdown language

Author: jcs090218

Assets/JCSUnity/Scripts/UI/Dropdown/JCS_DropdownLanguage.cs

@@ -0,0 +1,119 @@
+/**
+ * $File: JCS_DropdownLanguage.cs $
+ * $Date: 2025-04-15 01:14:38 $
+ * $Revision: $
+ * $Creator: Jen-Chieh Shen $
+ * $Notice: See LICENSE.txt for modification and distribution information
+ *                   Copyright © 2025 by Shen, Jen-Chieh $
+ */
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.UI;
+using TMPro;
+using MyBox;
+
+namespace JCSUnity
+{
+    /// <summary>
+    /// A dropdown menu let you choose the language.
+    /// </summary>
+    public class JCS_DropdownLanguage : JCS_DropdownObject
+    {
+        /* Variables */
+
+        [Separator("Initialize Variables (JCS_DropdownLanguage)")]
+
+        [Tooltip("List of supported languages.")]
+        [SerializeField]
+        private List<SystemLanguage> mOptions = new()
+        {
+            SystemLanguage.English,
+            SystemLanguage.ChineseTraditional,
+        };
+
+        [Tooltip("If true, remove all other options at the beginning.")]
+        [SerializeField]
+        private bool mRemoveAllOptions = true;
+
+        /* Setter & Getter */
+
+        public List<SystemLanguage> Options { get { return mOptions; } set { this.mOptions = value; } }
+        public bool RemoveAllOptions { get { return mRemoveAllOptions; } set { this.mRemoveAllOptions = value; } }
+
+        /* Functions */
+
+        private void Start()
+        {
+            Refresh();
+
+            AddListener();
+        }
+
+        private void AddListener()
+        {
+            mDropdownLegacy?.onValueChanged.AddListener(delegate
+            {
+                OnValueChanged_Legacy(mDropdownLegacy);
+            });
+
+            mDropdownTMP?.onValueChanged.AddListener(delegate
+            {
+                OnValueChanged_TMP(mDropdownTMP);
+            });
+
+            // Run once.
+            OnValueChanged_Legacy(mDropdownLegacy);
+            OnValueChanged_TMP(mDropdownTMP);
+        }
+
+        /// <summary>
+        /// Refresh all options once.
+        /// </summary>
+        public void Refresh()
+        {
+            if (mRemoveAllOptions)
+                ClearOptions();
+
+            foreach (SystemLanguage option in mOptions)
+            {
+                string text = JCS_Locale.SystemLangToString(option);
+
+                JCS_UIUtil.Dropdown_AddOption(this, text);
+            }
+
+            // Default to the current windowed mode.
+            {
+                string text = JCS_Locale.SystemLangToString(JCS_AppManager.instance.systemLanguage);
+
+                JCS_UIUtil.Dropdown_SetSelection(this, text);
+            }
+
+            JCS_UIUtil.Dropdown_RefreshSelection(this);
+        }
+
+        private void OnValueChanged_Legacy(Dropdown dropdown)
+        {
+            if (dropdown == null)
+                return;
+
+            string text = JCS_UIUtil.Dropdown_GetSelectedValue(dropdown);
+
+            OnValueChanged(text);
+        }
+        private void OnValueChanged_TMP(TMP_Dropdown dropdown)
+        {
+            if (dropdown == null)
+                return;
+
+            string text = JCS_UIUtil.Dropdown_GetSelectedValue(dropdown);
+
+            OnValueChanged(text);
+        }
+        private void OnValueChanged(string text)
+        {
+            SystemLanguage selected = JCS_Locale.StringToSystemLang(text);
+
+            JCS_AppManager.instance.systemLanguage = selected;
+        }
+    }
+}

Assets/JCSUnity/Scripts/UI/Dropdown/JCS_DropdownLanguage.cs.meta

@@ -22,7 +22,7 @@ public class JCS_DropdownWindowedMode : JCS_DropdownObject
     {
         /* Variables */
 
-        private List<string> mOptions = new List<string>()
+        private List<string> mOptions = new ()
         {
             "Full Screen",
             "Windowed",