1 /*

     2 * Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  layoutpreferences implementation class for flowlayoutmanager

    15 *

    16 */

    17 

    18 

    19 #ifndef ALFFLOWLAYOUTPREFERENCESIMPL_H

    20 #define ALFFLOWLAYOUTPREFERENCESIMPL_H

    21 

    22 #include <osn/osndefines.h>

    23 #include <alf/ialflayoutpreferences.h>

    24 

    25 using namespace Alf;

    26 

    27 namespace Alf

    28     {

    29 class AlfFlowLayoutManager;

    30 

    31 /**

    32  * layout preferences implementation for flowlayoutmanager.

    33  *

    34  * @lib alfwidgetmodel.lib

    35  * @since S60 ?S60_version

    36  */

    37 class AlfFlowLayoutPreferencesImpl : public IAlfLayoutPreferences

    38     {

    39 public:

    40     AlfFlowLayoutPreferencesImpl(AlfFlowLayoutManager& aFlowLayoutManager);

    41 public:

    42 // from base class IAlfLayoutPreferences

    43 

    44 	/**

    45 	 * Returns the minimum size of the layout by combining the minimum sizes of the

    46 	 * layed out visuals.

    47 	 * 

    48 	 * @param aMinSize The minimum size that the object would like to be laid out to

    49 	 * @return false iff none of the layed out UI elements do not care about minimum size

    50 	 */

    51 	virtual bool getMinimumSize( TAlfXYMetric& aMinSize ) const;

    52 	

    53 	/**

    54 	 * Returns the maximum size of the layout by combining the maximum sizes of the

    55 	 * layed out visuals.

    56 	 *  

    57 	 * @param aMaxSize The maximum size that the object would like to be laid out to

    58 	 * @return false iff none of the layed out UI elements do not care about maximum size

    59 	 */

    60 	virtual bool getMaximumSize( TAlfXYMetric& aMaxSize ) const;

    61 	

    62     /**

    63      * Returns the size combined by all preferred sizes of child UI elements in this layout 

    64      * when they are being layed out according to the layout manager rules.

    65      * 

    66      * @param aPreferredSize Filled with the referred area occupied by child elements when

    67      * 						 layed out by layouting rules in this layout manager.

    68      * @return False if none of the child components report their preferred size. True

    69      * 		   otherwise.

    70      */

    71     virtual bool getPreferredSize(TAlfXYMetric& aPreferredSize) const;

    72 	 

    73 	/**

    74 	 * Set the preferred size into a presentation object.

    75 	 * 

    76 	 * This is not supported on the layout manager. Users should set preferred sizes of the

    77 	 * contained UI elements.

    78 	 */

    79 	virtual void setPreferredSize( const TAlfXYMetric& aPreferredSize );

    80 // from base class IAlfInterfaceBase

    81     

    82     /**

    83      * Interface getter. 

    84      * @see IAlfInterfaceBase::makeInterface

    85      *

    86      * @since S60 ?S60_version

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

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

    89      *         supported or available.

    90      */    

    91     virtual IAlfInterfaceBase* makeInterface( const IfId& aType );

    92 protected:

    93 

    94     /** size type to calculate @see calculateChildSizes */

    95     enum sizeType

    96         {

    97         ESizePreferred,

    98         ESizeMin,

    99         ESizeMax

   100         };

   101         

   102 	/**

   103 	 * calculate the min-, preferred-, or max- sizes from the children. 

   104 	 * 

   105 	 * @param aSize on return, contains the calculated size.

   106 	 * @param aFlowDirection direction of flow.

   107 	 * @param aSizeType specifies, whether the min-, preferred- or max-size of the

   108 	 *        IAlfLayoutPreferences is used for calculation.

   109 	 */

   110     bool calculateChildSizes(TAlfXYMetric& aSize,  

   111         enum IAlfFlowLayoutPolicy::flowDirection aFlowDirection, 

   112         enum sizeType aSizeType) const;

   113         

   114 	/**

   115 	 * fetches the size from the IAlfLayoutPreferences-interface of the aControl.

   116 	 * 

   117 	 * @param aControl control, which preferences-interface to query.

   118 	 * @param aSize on return, contains the size.

   119 	 * @param aSizeType specifies, whether the min-, preferred- or max-size of the

   120 	 *        IAlfLayoutPreferences is returned.

   121 	 */

   122     bool getSize(CAlfWidgetControl* aControl, 

   123         TAlfXYMetric& aSize,

   124         enum sizeType aSizeType) const;

   125         

   126     /**

   127      * @return the flow layout policy-instance of the layoutmanager.

   128      *

   129      */

   130     const IAlfFlowLayoutPolicy& flowLayoutPolicy() const;

   131 

   132 	/**

   133 	 * converts size in metrics to size in pixels. Implementation missing.

   134 	 * 

   135 	 * @param aSize size to convert

   136 	 * @return size in pixels.

   137 	 */

   138     static TAlfRealSize sizeInPixels(const TAlfXYMetric& aSize);

   139     

   140 private:

   141     AlfFlowLayoutManager &mFlowLayoutManager;

   142     TAlfXYMetric mPreferredSize;

   143     };

   144 

   145     } // namespace Alf

   146 

   147 #endif // ALFFLOWLAYOUTPREFERENCESIMPL_H