--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/camerauis/cameraxui/cxengine/inc/cxestatemachine.h	Fri Apr 16 14:51:30 2010 +0300
@@ -0,0 +1,91 @@
+/*
+* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+#ifndef CXESTATEMACHINE_H
+#define CXESTATEMACHINE_H
+
+#include "cxestatemachinebase.h"
+
+class CxeState;
+
+/**
+ * CxeStateMachine extends CxeStateMachineBase functionality. All methods call base class
+ * implementation, and will panic if the base class return value indicates failure.
+ *
+ * Engine classes should derive from CxeStateMachine. CxeStateMachineBase is for situations where
+ * asserts can't be used, like unit testing.
+ *
+ * CxeStateMachine is internal to the engine and is not visible in the engine API.
+*/
+class CxeStateMachine : public CxeStateMachineBase
+{
+public:
+    /**
+    * CxeStateMachine constructor. After construction, the derived class should
+    * add all the defined states and call setInitialState().
+    *
+    * @sa addState setInitialState
+    * @param stateMachineName  Name for this state machine (used for debug prints)
+    */
+    CxeStateMachine(const char* stateMachineName);
+    virtual ~CxeStateMachine();
+
+protected:
+    /**
+     * Add a new state to the machine. Takes ownership of state. This function will
+     * panic, if new state id is incorrect.
+     *
+     * @param state A CxeState object defining a name, ID, and allowed transitions for
+     * the new state. The CxeState ID must be unique and not to contain overlapping bits
+     * with other state ids, since bitwise AND operator is used for the state ids.
+     * @return True if adding was successful, false if adding failed
+     */
+    bool addState(CxeState *state);
+
+    /**
+     * Initiate a state transition from current state to a given state ID. If the state
+     * transition is invalid, this function will panic.
+     *
+     * @param stateId State ID of the new state
+     * @param error   Optional error code to be associated with the transition
+     */
+    bool setState(int stateId, int error = 0);
+
+    /**
+     * Set the initial state of the state machine. Can be called only once.
+     * This method will panic, if initial state to be set is unknown, or initial
+     * state has already been set.
+     *
+     * @param stateId State ID for the initial state.
+     */
+    bool setInitialState(int stateId);
+
+    /**
+     * Pure virtual function to be implemented by derived classes. Called when state changes.
+     * The implementation should emit a signal informing interested parties of a state change.
+     *
+     * @param newStateId State ID for the new state
+     * @param error      An error code associated with the state transition
+     */
+    virtual void handleStateChanged(int newStateId, CxeError::Id error) = 0;
+
+private:
+
+};
+
+#endif // CXESTATEMACHINE_H
+
+