Utilities for reading Android Intent extras in Unity and mapping them directly onto C# data classes.

AndroidIntentExtras.cs

// ────────────────────────────────────────────────────────────────────────────────
// Description: Utilities for reading Android Intent extras in Unity and mapping
//              them directly onto C# data classes with strong typing.
// ────────────────────────────────────────────────────────────────────────────────

#nullable enable
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Reflection;
using UnityEngine;

namespace Common
{
    /// <summary>
    /// Decorates a property to indicate which <c>Intent</c> extra key supplies its
    /// value. If omitted, the property name itself is used as the key.
    /// </summary>
    [AttributeUsage(AttributeTargets.Property)]
    public sealed class IntentKeyAttribute : Attribute
    {
        public string Key { get; }
        public IntentKeyAttribute(string key) => Key = key;
    }

    /// <summary>
    /// Low-level API that talks directly to the Android <c>Intent</c>.
    /// </summary>
    public static class AndroidIntentExtras
    {
        // ────────────────────────────────────────────────────────────────────
        // PRIVATE HELPERS
        // ────────────────────────────────────────────────────────────────────

        private static AndroidJavaObject GetIntent()
        {
            var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
            var activity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity");
            return activity.Call<AndroidJavaObject>("getIntent");
        }

        private static string? JavaClassName(AndroidJavaObject obj) =>
            obj.Call<AndroidJavaObject>("getClass")?.Call<string>("getName");

        // ────────────────────────────────────────────────────────────────────
        // SNAPSHOT – Dictionary<string,object>
        // ────────────────────────────────────────────────────────────────────

        public static Dictionary<string, object> GetIntentExtras()
        {
            var dict = new Dictionary<string, object>();

#if UNITY_EDITOR
            return dict;
#endif
            using var intent = GetIntent();
            using var bundle = intent.Call<AndroidJavaObject>("getExtras");
            if (bundle == null) return dict;

            using var keySet = bundle.Call<AndroidJavaObject>("keySet");
            foreach (string key in keySet.Call<string[]>("toArray"))
            {
                using var obj = bundle.Call<AndroidJavaObject>("get", key);
                if (obj == null) continue;

                switch (JavaClassName(obj))
                {
                    case "java.lang.String":  dict[key] = obj.Call<string>("toString");   break;
                    case "java.lang.Boolean": dict[key] = obj.Call<bool>("booleanValue"); break;
                    case "java.lang.Integer": dict[key] = obj.Call<int>("intValue");      break;
                    case "java.lang.Long":    dict[key] = obj.Call<long>("longValue");    break;
                    case "java.lang.Float":   dict[key] = obj.Call<float>("floatValue");  break;
                    default:                  dict[key] = obj.Call<string>("toString");   break;
                }
            }
            return dict;
        }

        // ────────────────────────────────────────────────────────────────────
        // GENERIC TYPED GETTER - CORRECTED VERSION
        // ────────────────────────────────────────────────────────────────────

        public static bool TryGet<T>(string key, out T? value)
        {
            value = default;
#if UNITY_EDITOR
            return false;
#endif
            using var intent = GetIntent();

            if (!intent.Call<bool>("hasExtra", key)) return false;

            // Always use Bundle to get the actual type, then convert appropriately
            using var bundle = intent.Call<AndroidJavaObject>("getExtras");
            if (bundle == null) return false;

            using var obj = bundle.Call<AndroidJavaObject>("get", key);
            if (obj == null) return false;

            var javaClassName = JavaClassName(obj);
            object? raw = null;

            try
            {
                // First, get the value based on its actual Java type
                switch (javaClassName)
                {
                    case "java.lang.String":
                        raw = obj.Call<string>("toString");
                        break;
                    case "java.lang.Boolean":
                        raw = obj.Call<bool>("booleanValue");
                        break;
                    case "java.lang.Integer":
                        raw = obj.Call<int>("intValue");
                        break;
                    case "java.lang.Long":
                        raw = obj.Call<long>("longValue");
                        break;
                    case "java.lang.Float":
                        raw = obj.Call<float>("floatValue");
                        break;
                    case "java.lang.Double":
                        raw = obj.Call<double>("doubleValue");
                        break;
                    default:
                        // Unknown type - get as string
                        raw = obj.Call<string>("toString");
                        break;
                }

                // If we have a type mismatch, try to convert
                if (raw != null && raw.GetType() != typeof(T))
                {
                    // Special handling for bool conversions from string
                    if (typeof(T) == typeof(bool) && raw is string str)
                    {
                        if (bool.TryParse(str, out var b))
                            raw = b;
                        else if (str is "1" or "yes" or "YES" or "true" or "TRUE")
                            raw = true;
                        else if (str is "0" or "no" or "NO" or "false" or "FALSE")
                            raw = false;
                        else if (string.IsNullOrEmpty(str))
                            raw = true; // presence flag
                        else
                            return false; // Can't convert
                    }
                    // Special handling for numeric conversions
                    else if (raw is string strNum)
                    {
                        if (typeof(T) == typeof(int) && int.TryParse(strNum, NumberStyles.Any, CultureInfo.InvariantCulture, out var i))
                            raw = i;
                        else if (typeof(T) == typeof(long) && long.TryParse(strNum, NumberStyles.Any, CultureInfo.InvariantCulture, out var l))
                            raw = l;
                        else if (typeof(T) == typeof(float) && float.TryParse(strNum, NumberStyles.Any, CultureInfo.InvariantCulture, out var f))
                            raw = f;
                        else if (typeof(T) == typeof(double) && double.TryParse(strNum, NumberStyles.Any, CultureInfo.InvariantCulture, out var d))
                            raw = d;
                        else
                        {
                            // Generic conversion attempt
                            try
                            {
                                raw = Convert.ChangeType(strNum, typeof(T), CultureInfo.InvariantCulture);
                            }
                            catch
                            {
                                return false;
                            }
                        }
                    }
                    else
                    {
                        // Try generic conversion
                        try
                        {
                            raw = Convert.ChangeType(raw, typeof(T), CultureInfo.InvariantCulture);
                        }
                        catch
                        {
                            return false;
                        }
                    }
                }

                if (raw is T cast)
                {
                    value = cast;
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.LogError($"Failed to get extra '{key}' as {typeof(T).Name}: {ex.Message}");
            }

            return false;
        }

        // ────────────────────────────────────────────────────────────────────
        // PRESENCE-ONLY FLAG
        // ────────────────────────────────────────────────────────────────────

        public static bool HasExtra(string key)
        {
#if UNITY_EDITOR
            return false;
#endif
            using var intent = GetIntent();
            return intent.Call<bool>("hasExtra", key);
        }

        // ────────────────────────────────────────────────────────────────────
        // BACK-COMPAT WRAPPERS
        // ────────────────────────────────────────────────────────────────────

        public static bool TryGetString(string key, out string value) =>
            TryGet<string>(key, out value);

        public static bool HasIntent(string key) => HasExtra(key);

        // ────────────────────────────────────────────────────────────────────
        // "WERE WE LAUNCHED WITH *ANY* ARGUMENTS?"
        // ────────────────────────────────────────────────────────────────────

        public static bool HasAnyExtras()
        {
#if UNITY_EDITOR
            return false;
#endif
            using var intent = GetIntent();
            using var bundle = intent.Call<AndroidJavaObject>("getExtras");
            if (bundle == null) return false;

            int count = bundle.Call<int>("size");
            return count > 0;
        }
    }

    // ════════════════════════════════════════════════════════════════════════════
    // High-level reflection mapper
    // ════════════════════════════════════════════════════════════════════════════

    public static class AndroidIntentMapper
    {
        public static T FromIntentExtras<T>() where T : new()
        {
            T instance = new T();
            var props = typeof(T).GetProperties(
                            BindingFlags.Instance |
                            BindingFlags.Public |
                            BindingFlags.NonPublic);

            foreach (PropertyInfo p in props)
            {
                if (!p.CanWrite) continue;

                // ── 1. Resolve key ──────────────────────────────────────────
                var attr = p.GetCustomAttribute<IntentKeyAttribute>();
                string key = attr?.Key ?? p.Name;

                // ── 2. Try to get the value (the improved TryGet handles all cases)
                if (TryGetExact(p.PropertyType, key, out object? exact))
                {
                    p.SetValue(instance, exact);
                }
            }
            return instance;
        }

        // ────────────────────────────────────────────────────────────────────
        // REFLECTION HELPER – dynamic generic call
        // ────────────────────────────────────────────────────────────────────

        private static bool TryGetExact(Type t, string key, out object? val)
        {
            var m = typeof(AndroidIntentExtras)
                        .GetMethod(nameof(AndroidIntentExtras.TryGet))!
                        .MakeGenericMethod(t);

            object[] args = { key, null! };
            bool ok = (bool)m.Invoke(null, args)!;
            val = args[1];
            return ok;
        }
    }
}

C# Property Type	Read Path in AndroidIntentMapper	Recommended ADB Flag(s)¹	Example am start Snippet
string	getStringExtra → or ToString() fallback	-e / --es	--es username "alice"
bool	getBooleanExtra → smart-parse ("true", "1", empty)	--ez	--ez isPremiumUser true —or— --ez isPremiumUser
int	getIntExtra → int.Parse fallback	--ei	--ei age 42
long	getLongExtra → long.Parse fallback	--el	--el score 9876543210
float	getFloatExtra → float.Parse fallback	--ef	--ef ratio 3.14
double	via string parse (double.Parse)	--es	--es price "99.95"
enum (any)	string parse → Enum.TryParse (case-insensitive)	--es	--es role "Admin"
DateTime	string/long parse → ISO-8601 or epoch seconds	--es / --el	--es expires "2025-12-31T23:59:59Z" --el expires 1767225599
any other convertible type	Convert.ChangeType fallback	--es	--es misc "value"

¹ Short form flags (-e) are valid only for strings; all others require the long form.