/*

* Copyright (c) 2007 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:  flow layout policy.

*

*/

#ifndef I_ALFFLOWLAYOUTPOLICY

#define I_ALFFLOWLAYOUTPOLICY

#include <alf/ialfinterfacebase.h>

#include <alf/alftypes.h>

namespace Alf

    {

namespace ialfflowlayoutpolicy

    {

     static const IfId Ident =

        {

        0, "flowlayoutpolicy"

        };

    }

/**

 * interface for flow layout policy. The policy-interface can be queried

 * from the layoutmanager using the makeInterface- call. 

 * @see IAlfLayoutManager

 *

 * @lib alfwidgetmodel.lib

 * @since S60 ?S60_version

 * @status Draft

 */

class IAlfFlowLayoutPolicy : public IAlfInterfaceBase

    {

public:

    /** Flow directions. */

    enum flowDirection

        {

        /**

         * Flow horizontally. System wide layout mirroring is considered

         * to determine whether visuals are layed from left to right

         * or from right to left.

         */

        EFlowHorizontal,

        /** Flow vertically. */

        EFlowVertical

        };

    /** Mode flags that specify how the flow is laid out. */

    enum flowModeFlags

        {

        /** Center the children perpendicular to the flow direction.

            For example, if the flow direction is horizontal (left->right)

            this flag will center the children vertically along the flow. */

        EFlowModeCenterPerpendicular = 0x1,

        /** Fit the children perpendicular to the flow direction.

            For example, if the flow direction is horizontal, the children

            will be vertically resized to fit the layout's rectangle. */

        EFlowModeFitPerpendicular = 0x2

        };

public:

    static inline const IfId& type()

        {

        return ialfflowlayoutpolicy::Ident;

        }

    virtual inline ~IAlfFlowLayoutPolicy() {}

    /**

     * Sets the direction of the flow.

     *

     * @param aDirection  Flow direction.

     */    

    virtual void setFlowDirection(enum flowDirection aDirection) = 0;

    /**

     * returns the flow direction

     *

     * @param aDirection  Flow direction.

     */    

    virtual enum flowDirection flowDirection() const = 0;

    /**

     * Sets the mode of the flow. The mode flags determine how the flow layout

     * behaves.

     *

     * @param aMode  Mode flags (OR'd together).

     *

     * @see IAlfFlowLayoutPolicy::flowModeFlags

     */

    virtual void setMode(int aMode) = 0;

    /**

     * Returns the mode flags of the flow.

     *

     * @see IAlfFlowLayoutPolicy::flowModeFlags

     *

     * @return  Returns the current mode flags.

     */

    virtual int mode() const = 0;

public:

// from base class IAlfInterfaceBase

    /**

     * Interface getter. 

     * @see IAlfInterfaceBase::MakeInterface

     *

     * @since S60 ?S60_version

     * @param aType The type id of the queried interface.

     * @return The queried interface, or NULL if the interface is not

     *         supported or available.

     */    

    virtual IAlfInterfaceBase* makeInterface( const IfId& aType ) = 0;

    };

    } // namespace Alf

#endif // I_ALFFLOWLAYOUTPOLICY