More project base

src/Core/FileTime.Core.Abstraction/FileTime.Core.Abstraction.csproj

@@ -10,4 +10,8 @@
     <PackageReference Include="System.Reactive" Version="5.0.0" />
   </ItemGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\..\Library\InitableService\InitableService.csproj" />
+  </ItemGroup>
+
 </Project>

src/Core/FileTime.Core.Abstraction/Models/Constants.cs

@@ -3,5 +3,6 @@ namespace FileTime.Core.Models
     public static class Constants
     {
         public const char SeparatorChar = '/';
+        public const int MaximumObservableMergeOperations = 4;
     }
 }

src/Core/FileTime.Core.Abstraction/Services/ITab.cs

@@ -1,7 +1,14 @@
+using FileTime.Core.Models;
+using InitableService;
+
 namespace FileTime.Core.Services
 {
-    public interface ITab
+    public interface ITab : IInitable<IContainer>
     {
-        
+        IObservable<IContainer?> CurrentLocation { get; }
+        IObservable<IAbsolutePath?> CurrentSelectedItem { get; }
+        IObservable<IEnumerable<IItem>> CurrentItems { get; }
+
+        void ChangeLocation(IContainer newLocation);
     }
 }