/*

* 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:   Viewport layout definition.

*

*/

#ifndef C_ALFVIEWPORTLAYOUT_H

#define C_ALFVIEWPORTLAYOUT_H

#include <alf/alflayout.h>

/**

 *  Viewport layout

 *  Usage:

 *  @code

 *  // Aim is to zoom into one of the grids of icons using a viewport layout.

 *

 *  // Create a anchor layout and grid layout into the parent anchor layout and 

 *  // populate it with application icons.

 * 

 *  // The viewport layout sits in the middle of the screen.

 *   parent->SetRelativeAnchorRect(1, EAlfAnchorOriginHCenter, EAlfAnchorOriginVCenter, TAlfRealPoint(-0.2, -0.2),

 *                                    EAlfAnchorOriginHCenter, EAlfAnchorOriginVCenter, TAlfRealPoint(0.2, 0.2));

 *   

 *   // Create the viewport.

 *   CAlfViewportLayout* viewport = CAlfViewportLayout::AddNewL(*this, parent);

 * 

 *  // Set our virtual coordinate system to be based on the number of items in the grid (KNumGridItems).

 *   viewport->SetVirtualSize(TAlfRealSize(KNumGridItems, 1.0), 0);

 *   

 *   // Set the size and position of the viewport to look at the middle icon in the list.

 *   viewport->SetViewportSize(TAlfRealSize(2, 1.0/6.0), 0);

 *   viewport->SetViewportPos(TAlfRealPoint(TReal32(KNumGridItems/2)-1.0f, 5.0/12.0), 0);

 *   

 *   // This anchor layout will contain a strip of large icons clipped by the viewport window.

 *   CAlfAnchorLayout* zoomedParent = CAlfAnchorLayout::AddNewL(*this, viewport);     

 *   

 *  @endcode

 * 

 *  @lib alfclient.lib

 *  @since S60 v3.2

 */

class CAlfViewportLayout : public CAlfLayout

    {

public:

    /**

     * Two-phased constructor, which attach new object into the control.

     * @param aOwnerControl Control that owns this new obejct.

     * @param aParentLayout If given, the new object is set as child.

     */

    IMPORT_C static CAlfViewportLayout* AddNewL(CAlfControl& aOwnerControl,

                                            CAlfLayout* aParentLayout = 0);

    /**

     * Constructor.

     */

    IMPORT_C CAlfViewportLayout();

    /**

     * Second-phase constructor.

     */

    IMPORT_C void ConstructL(CAlfControl& aOwner);

    /**

     * Virtual destructor.

     */

    IMPORT_C ~CAlfViewportLayout();

    /** @beginAPI */

	/**

	 * Set virtual size of the viewable area.

	 *

	 * This is different from the physical size of the viewport -

	 * it defines the coordinate space that is used for scrolling.

	 * To use a normalised (u, v) coordinate mapping system, set aSize to (,1.0, 1.0).

	 *

	 * @param aSize The bottom-right corner of the child visual, in the units you wish to use for positioning the viewport.

	 * @param aTransitionTime The time it will take to complete the resizing of the virtual size.

	 */

    IMPORT_C void SetVirtualSize(const TAlfRealSize& aSize, TInt aTransitionTime);

	/**

	 * Set size of the viewport area.

	 *

	 * This is the size of the "window" we are using to look at the visual.

	 *

	 * @param aSize The size of the viewport in the units defined by SetVirtualSize().

	 * @param aTransitionTime The time it will take to complete the resizing of the viewport area.

	 * @see SetVirtualSize, SetViewportPos

	 */

    IMPORT_C void SetViewportSize(const TAlfRealSize& aSize, TInt aTransitionTime);

	/**

	 * Set position of the viewport area.

	 *

	 * This is the offset of the "window" we are using to look at the visual.

	 *

	 * @param aSize The size of the viewport in the units defined by SetVirtualSize().

	 * @param aTransitionTime The time it will take to complete moving the viewport area.

	 * @see SetVirtualSize, SetViewportSize

	 */

    IMPORT_C void SetViewportPos(const TAlfRealPoint& aPos, TInt aTransitionTime);

    /** @endAPI */

    /**

     * From CAlfVisual

     * @see CAlfVisual

     */

    IMPORT_C void RemoveAndDestroyAllD();

    IMPORT_C void UpdateChildrenLayout(TInt aTransitionTime = 0);

    IMPORT_C CAlfVisual* FindTag(const TDesC8& aTag);

    /** 

     * From CAlfLayout

     * @see CAlfLayout

     */

    IMPORT_C TAlfXYMetric BaseUnit() const; 

protected:

    /**

     * From CAlfVisual

     * @see CAlfVisual

     */

    IMPORT_C void DoRemoveAndDestroyAllD();

    IMPORT_C void PropertyOwnerExtension(const TUid& aExtensionUid, TAny** aExtensionParams);

private:

    // Private data structure. Owned.

    struct TViewportLayoutPrivateData;

    TViewportLayoutPrivateData* iViewportLayoutData;

    };

#endif // C_ALFVIEWPORTLAYOUT_H