* CachingFileStorage: Added more callbacks to provide user with more information what's going on

* Changed TestCacheSupervisor for easier use of the many callbacks
* Adapted tests for new callbacks

* GroupBaseActivity: Added sync menu command
* Preferences: Added option to enable/disable offline caching
* App: don't lock database when user wants to reload. This is done in PasswordActivity and should be done there after the password was filled into the pw field
* CheckDatabaseForChanges.cs: used when syncing a non-cached database

src/Kp2aUnitTests/TestCacheSupervisor.cs

@@ -1,29 +1,78 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using KeePassLib.Serialization;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
 using keepass2android.Io;
 
 namespace Kp2aUnitTests
 {
 	class TestCacheSupervisor: ICacheSupervisor
 	{
-		public bool CouldntOpenFromRemoteCalled { get; set; }
-		public bool CouldntSaveToRemoteCalled { get; set; }
-		public bool NotifyOpenFromLocalDueToConflictCalled { get; set; }
+		public const string CouldntOpenFromRemoteId = "CouldntOpenFromRemote";
+		public const string CouldntSaveToRemoteId = "CouldntSaveToRemote";
+		public const string NotifyOpenFromLocalDueToConflictId = "CouldntSaveToRemote";
+		public const string UpdatedCachedFileOnLoadId = "UpdatedCachedFileOnLoad";
+		public const string LoadedFromRemoteInSyncId = "LoadedFromRemoteInSync";
+		public const string UpdatedRemoteFileOnLoadId = "UpdatedRemoteFileOnLoad";
 
+		private HashSet<string> _callsMade = new HashSet<string>();
+		
+		public void Reset()
+		{
+			_callsMade.Clear();
+		}
+
+		public void AssertNoCall()
+		{
+			string allCalls = _callsMade.Aggregate("", (current, s) => current + s + ",");
+			Assert.AreEqual("", allCalls);
+		}
+
+		public void AssertSingleCall(string id)
+		{
+			if ((_callsMade.Count == 1)
+			    && _callsMade.Single() == id)
+			{
+				Reset();
+				return;
+			}
+				
+
+			Assert.Fail("expected only "+id+", but received: "+_callsMade.Aggregate("", (current, s) => current + s + ","));
+
+		}
 
 		public void CouldntSaveToRemote(IOConnectionInfo ioc, Exception e)
 		{
-			CouldntSaveToRemoteCalled = true;
+			_callsMade.Add(CouldntSaveToRemoteId);
 		}
 
 		public void CouldntOpenFromRemote(IOConnectionInfo ioc, Exception ex)
 		{
-			CouldntOpenFromRemoteCalled = true;
+			_callsMade.Add(CouldntOpenFromRemoteId);
+		}
+
+		public void UpdatedCachedFileOnLoad(IOConnectionInfo ioc)
+		{
+			_callsMade.Add(UpdatedCachedFileOnLoadId);
+		}
+
+		public void UpdatedRemoteFileOnLoad(IOConnectionInfo ioc)
+		{
+			_callsMade.Add(UpdatedRemoteFileOnLoadId);
 		}
 
 		public void NotifyOpenFromLocalDueToConflict(IOConnectionInfo ioc)
 		{
-			NotifyOpenFromLocalDueToConflictCalled = true;
+			_callsMade.Add(NotifyOpenFromLocalDueToConflictId);
 		}
+
+		public void LoadedFromRemoteInSync(IOConnectionInfo ioc)
+		{
+			_callsMade.Add(LoadedFromRemoteInSyncId);
+		}
+
+		
 	}
 }