introduce a TransientNavigationStore to share objects from one state to the next state

Toolkit.Avalonia/TransientNavigationStore.cs

@@ -0,0 +1,36 @@
+namespace Toolkit.Avalonia;
+
+public class TransientNavigationStore<TControl> : ITransientNavigationStore<TControl>
+    where TControl : class
+{
+    private readonly Dictionary<TControl, Dictionary<Type, object>> controlDataMap = [];
+
+    public void Set(TControl control, 
+        object parameters)
+    {
+        if (!controlDataMap.TryGetValue(control, out var typeMap))
+        {
+            typeMap = new Dictionary<Type, object>();
+            controlDataMap[control] = typeMap;
+        }
+
+        typeMap[parameters.GetType()] = parameters;
+    }
+
+    public T? Get<T>(TControl control)
+        where T : class
+    {
+        if (controlDataMap.TryGetValue(control, out var typeMap) &&
+            typeMap.TryGetValue(typeof(T), out var parameters))
+        {
+            typeMap.Remove(typeof(T));
+            return parameters as T;
+        }
+
+        return default;
+    }
+
+    public void Remove(TControl control) => controlDataMap.Remove(control);
+
+    public void Clear() => controlDataMap.Clear();
+}