bug fix: prepareFileUsage didn't work when file was cached but device offline

src/Kp2aBusinessLogic/Io/BuiltInFileStorage.cs

@@ -169,7 +169,7 @@ namespace keepass2android.Io
 			}
 		}
 
-		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode)
+		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode, bool alwaysReturnSuccess)
 		{
 			Intent intent = new Intent();
 			activity.IocToIntent(intent, ioc);

src/Kp2aBusinessLogic/Io/CachingFileStorage.cs

@@ -451,9 +451,10 @@ namespace keepass2android.Io
 			_cachedStorage.StartSelectFile(activity, isForSave, requestCode, protocolId);
 		}
 
-		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode)
+		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode, bool alwaysReturnSuccess)
 		{
-			_cachedStorage.PrepareFileUsage(activity, ioc, requestCode);
+			//we try to prepare the file usage by the underlying file storage but if the ioc is cached, set the flag to ignore errors 
+			_cachedStorage.PrepareFileUsage(activity, ioc, requestCode, alwaysReturnSuccess || IsCached(ioc));
 		}
 
 		public void OnCreate(IFileStorageSetupActivity activity, Bundle savedInstanceState)

src/Kp2aBusinessLogic/Io/FileStorageSetupInitiatorActivity.cs

@@ -9,7 +9,7 @@ namespace keepass2android.Io
 	public interface IFileStorageSetupInitiatorActivity
 	{
 		void StartSelectFileProcess(IOConnectionInfo ioc, bool isForSave, int requestCode);
-		void StartFileUsageProcess(IOConnectionInfo ioc, int requestCode);
+		void StartFileUsageProcess(IOConnectionInfo ioc, int requestCode, bool alwaysReturnSuccess);
 		void OnImmediateResult(int requestCode, int result, Intent intent);
 
 		Activity Activity { get;  }

src/Kp2aBusinessLogic/Io/IFileStorage.cs

@@ -21,6 +21,7 @@ namespace keepass2android.Io
 		public static String ProcessNameFileUsageSetup = "FILE_USAGE_SETUP";
 
 		public static String ExtraProcessName = "EXTRA_PROCESS_NAME";
+		public static String ExtraAlwaysReturnSuccess = "EXTRA_ALWAYS_RETURN_SUCCESS";
 		public static String ExtraPath = "PATH";
 		public static String ExtraIsForSave = "IS_FOR_SAVE";
 		public static String ExtraErrorMessage = "EXTRA_ERROR_MESSAGE";
@@ -136,8 +137,11 @@ namespace keepass2android.Io
 		/// <summary>
 		/// Initiates the process for choosing a file in the given file storage.
 		/// The file storage should either call OnImmediateResult or StartFileUsageProcess
+		/// If alwaysReturnSuccess is true, the activity should be finished with ResultCode Ok.
+		/// This can make sense if a higher-level file storage has the file cached by still wants to 
+		/// give the cached storage the chance to initialize file access.
 		/// </summary>
-		void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode);
+		void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode, bool alwaysReturnSuccess);
 
 		//Setup methods: these are called from the setup activity so the file storage can handle UI events for authorization etc.
 		void OnCreate(IFileStorageSetupActivity activity, Bundle savedInstanceState);

src/Kp2aBusinessLogic/Io/JavaFileStorage.cs

@@ -98,7 +98,7 @@ namespace keepass2android.Io
 			Kp2aLog.Log(e.Message);
 			var ex = new Exception(e.LocalizedMessage ?? 
 				e.Message ?? 
-				_app.GetResourceString(UiStringKey.ErrorOcurred)+e, e);
+				_app.GetResourceString(UiStringKey.ErrorOcurred)+e.GetType().Name, e);
 			return ex; 
 		}
 
@@ -249,9 +249,9 @@ namespace keepass2android.Io
 			_jfs.StartSelectFile((IJavaFileStorageFileStorageSetupInitiatorActivity) activity, isForSave, requestCode);
 		}
 
-		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode)
+		public void PrepareFileUsage(IFileStorageSetupInitiatorActivity activity, IOConnectionInfo ioc, int requestCode, Boolean alwaysReturnSuccess)
 		{
-			_jfs.PrepareFileUsage((IJavaFileStorageFileStorageSetupInitiatorActivity)activity, IocToPath(ioc), requestCode);
+			_jfs.PrepareFileUsage((IJavaFileStorageFileStorageSetupInitiatorActivity)activity, IocToPath(ioc), requestCode, alwaysReturnSuccess);
 		}
 
 		public void OnCreate(IFileStorageSetupActivity activity, Bundle savedInstanceState)

src/Kp2aBusinessLogic/Kp2aBusinessLogic.csproj

@@ -20,7 +20,7 @@
     <DebugType>full</DebugType>
     <Optimize>false</Optimize>
     <OutputPath>bin\Debug\</OutputPath>
-    <DefineConstants>TRACE;DEBUG;EXCLUDE_TWOFISH;INCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;EXCLUDE_FILECHOOSER;EXCLUDE_JAVAFILESTORAGE</DefineConstants>
+    <DefineConstants>TRACE;DEBUG;EXCLUDE_TWOFISH;INCLUDE_KEYBOARD;EXCLUDE_KEYTRANSFORM;INCLUDE_FILECHOOSER;INCLUDE_JAVAFILESTORAGE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>