diff -r 000000000000 -r 4e91876724a2 photosgallery/viewframework/medialists/src/glxattributecontext.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/photosgallery/viewframework/medialists/src/glxattributecontext.cpp	Thu Dec 17 08:45:44 2009 +0200
@@ -0,0 +1,374 @@
+/*
+* Copyright (c) 2008-2009 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:    Generic fetch context to retrieve attributes
+*
+*/
+
+#include <AknUtils.h>
+
+#include "glxattributecontext.h"
+#include "mglxmedialist.h"
+#include "glxerrormanager.h"
+#include "glxtracer.h"
+#include "glxlog.h"
+#include "glxlistutils.h"
+
+// Default granularity of items to request for
+const TUint KGlxAttributeContextDefaultGranularity = 200;
+
+const TInt KVisibleItemsCorrectionValue = 1;
+const TInt KVisibleItemsModFactor = 2;
+
+// -----------------------------------------------------------------------------
+// Constructor
+// -----------------------------------------------------------------------------
+//
+EXPORT_C CGlxAttributeContext::CGlxAttributeContext(MGlxMediaListIterator* aIterator) :
+        iIterator(aIterator),
+        iGranularity(KGlxAttributeContextDefaultGranularity)
+    {
+    TRACER("CGlxAttributeContext::Default Constructor");
+    
+    __ASSERT_DEBUG(aIterator, Panic(EGlxPanicNullPointer));
+    }
+
+// -----------------------------------------------------------------------------
+// Destructor
+// -----------------------------------------------------------------------------
+//
+EXPORT_C CGlxAttributeContext::~CGlxAttributeContext()
+    {
+    TRACER("CGlxAttributeContext:: Destructor");
+    
+    iAttributes.Close();
+    }
+
+// -----------------------------------------------------------------------------
+// Adds an attribute to be retrieved for all items
+// -----------------------------------------------------------------------------
+//
+EXPORT_C void CGlxAttributeContext::AddAttributeL(const TMPXAttribute& aAttribute)
+    {
+    TRACER("CGlxAttributeContext::AddAttributeL");
+    
+    // Check that the attribute is not added twice
+    TIdentityRelation<TMPXAttribute> match (&TMPXAttribute::Match);
+    TInt index = iAttributes.Find(aAttribute, match);
+
+    // Add the attribute
+    if (KErrNotFound == index) 
+        {
+        iAttributes.AppendL(aAttribute);
+        }
+    }
+
+// -----------------------------------------------------------------------------
+// Removes an attribute from the "retrieval instructions"
+// -----------------------------------------------------------------------------
+//
+EXPORT_C void CGlxAttributeContext::RemoveAttribute(const TMPXAttribute& aAttribute)
+    {
+    TRACER("CGlxAttributeContext::RemoveAttribute");
+    
+    // Check that the attribute to be removed exists
+    TIdentityRelation<TMPXAttribute> match (&TMPXAttribute::Match);
+    TInt index = iAttributes.Find(aAttribute, match);
+
+    // Remove the attribute
+    if (KErrNotFound != index) 
+        {
+        iAttributes.Remove(index);
+        }
+    }
+
+// -----------------------------------------------------------------------------
+// CGlxDefaultAttributeContext::AttributeCount
+// -----------------------------------------------------------------------------
+//	
+EXPORT_C TInt CGlxAttributeContext::AttributeCount()
+	{
+	TRACER("CGlxAttributeContext::AttributeCount");
+	
+	return iAttributes.Count();
+	}
+
+// -----------------------------------------------------------------------------
+// Sets granularity of the item index array returned from AttributeRequestL
+// -----------------------------------------------------------------------------
+EXPORT_C void CGlxAttributeContext::SetGranularity(TUint aGranularity)
+    {
+    TRACER("CGlxAttributeContext::SetGranularity");
+    
+    iGranularity = aGranularity;
+    }
+
+// -----------------------------------------------------------------------------
+// Get attributes request for an item
+// From MGlxFetchContext
+// -----------------------------------------------------------------------------
+//
+TInt CGlxAttributeContext::AttributeRequestL(const MGlxMediaList* aList, 
+        RArray<TInt>& aItemIndices, RArray<TMPXAttribute>& aAttributes, 
+        CMPXAttributeSpecs*& /*aDetailedSpecs*/) const
+    {
+    TRACER("CGlxAttributeContext::AttributeRequestL");
+    
+    TInt itemCount = aList->Count();
+    if (0 == itemCount || !iIterator) 
+        {
+        return 0;
+        }
+
+    // Check through the items in the order defined by the iterator
+    iIterator->SetToFirst(aList);
+
+    // Loop until iterator does not give any more indexes or granularity reached
+    TInt index = KErrNotFound;
+    TInt error = KErrNone;
+    TBool firstItem = ETrue;
+    TInt defaultVisItems = GlxListUtils::VisibleItemsGranularityL();
+    if (defaultVisItems%KVisibleItemsModFactor == 0)
+        {
+        defaultVisItems += KVisibleItemsCorrectionValue;
+        }
+            
+    while ((KErrNotFound != (index = (*iIterator)++)) && (aItemIndices.Count() < iGranularity) && (KErrNone == error))
+        {
+        // Check if this item is lacking attributes
+        TBool attributesAdded = AddItemAttributesL(index, aList, aAttributes, error, firstItem);
+        if (attributesAdded)
+            {
+            aItemIndices.AppendL(index);
+            GLX_DEBUG3("CGlxAttributeContext::AttributeRequestL() index=%d, Media Id=%d", 
+                                                    index, aList->Item(index).Id().Value());
+            firstItem = EFalse;
+                              
+            // Fetch the visible items attrib first
+            if (aItemIndices[0] == (aList->VisibleWindowIndex()+ (defaultVisItems/2))
+                && aItemIndices.Count() == defaultVisItems)
+                {
+                GLX_DEBUG1("Break to fetch the visible items attrib first");
+                break;
+				}
+            }
+        else if ( firstItem && ( error != KErrNone ) )
+            {
+            // Continue iterating through the list
+            // if the first item had errors
+            // See EMYP-79VDHP
+            error = KErrNone;
+            }
+        }
+
+    // If an error was found, return KErrGeneral
+    if (error != KErrNone)
+        {
+        return KErrGeneral;
+        }
+
+    GLX_DEBUG2("CGlxAttributeContext::AttributeRequestL() aItemIndices.Count()=%d",
+                                      aItemIndices.Count());
+    return aItemIndices.Count();
+    }
+
+// -----------------------------------------------------------------------------
+// Get all attributes required for the item (whether the are fetched or not)
+// From MGlxFetchContext
+// -----------------------------------------------------------------------------
+//
+void CGlxAttributeContext::AllAttributesL(const MGlxMediaList* aList, TInt aListIndex, 
+        RArray<TMPXAttribute>& aAttributes) const 
+    {
+    TRACER("CGlxAttributeContext::AllAttributesL");
+    
+    // An empty request makes no sense, but won't do any harm.
+
+    // If no iterator, no request
+    if (!iIterator || !iAttributes.Count())
+        {
+        return;
+        }
+	
+    // No requests outside range
+    iIterator->SetToFirst(aList);
+    if (!iIterator->InRange(aListIndex))
+        {
+        return;
+        }
+
+    // Just list all attributes specified for this context
+    TInt count = iAttributes.Count();
+    for (TInt i = 0; i < count; i++) 
+        {
+        aAttributes.AppendL(iAttributes[i]);
+        }
+    }
+
+// -----------------------------------------------------------------------------
+// Number of current requests
+// From MGlxFetchContext
+// -----------------------------------------------------------------------------
+TInt CGlxAttributeContext::RequestCountL(const MGlxMediaList* aList) const
+    {
+    TRACER("CGlxAttributeContext::RequestCountL");
+    
+    RArray<TInt> itemIndices;
+    CleanupClosePushL(itemIndices);
+
+    RArray<TMPXAttribute> attributes;
+    CleanupClosePushL(attributes);
+
+    CMPXAttributeSpecs* attrSpecs = NULL;
+
+    TInt requestCount = AttributeRequestL(aList, itemIndices, attributes, attrSpecs);
+
+    delete attrSpecs;
+
+    CleanupStack::PopAndDestroy(&attributes);
+    CleanupStack::PopAndDestroy(&itemIndices);
+
+    return requestCount;
+    }
+
+// -----------------------------------------------------------------------------
+// Check if the item at the index requires any attributes to be added to request
+// -----------------------------------------------------------------------------
+TBool CGlxAttributeContext::AddItemAttributesL(TInt aIndexInList, 
+        const MGlxMediaList* aList, RArray<TMPXAttribute>& aAttributes,
+        TInt& aError, TBool aFirstItem) const
+    {
+    TRACER("CGlxAttributeContext::AddItemAttributesL");
+    
+    TInt attributesAdded = EFalse;
+
+    const TGlxMedia& m = aList->Item(aIndexInList);
+    if (!m.IsStatic())
+    	{
+    	const CGlxMedia* media = m.Properties();
+	    TInt attributeCount = iAttributes.Count();
+	    if (!media)
+	        {
+	        // There are no attributes for this item
+	        // Add all attributes
+	        for (TInt count = 0; count < attributeCount; ++count)
+	            {
+	            AddItemAttributeL(aAttributes, iAttributes[count]);
+	            }
+	
+	        if ( attributeCount > 0 )
+	            {
+	            attributesAdded = ETrue;
+	            }
+	        }
+	    else
+	        {
+	        if ( GlxErrorManager::HasError(media) )
+	            {
+	            // Item has one or more errors on its attributes
+	            // Check if we are going to try to add an attribute that may have an error on it
+	            for (TInt count = 0; (count < attributeCount) && (KErrNone == aError); ++count)
+	                {
+	                aError = GlxErrorManager::HasAttributeErrorL(media, iAttributes[count]);
+	                }
+	            }
+	
+	        // Always allow attribute adding if it's the first item
+	        if ( KErrNone == aError || aFirstItem )
+	            {
+	            // There may be some attributes for this item
+	            // Add attributes that don't exist yet
+	            for (TInt count = 0; count < attributeCount; ++count)
+	                {
+	                const TMPXAttribute& attribute = iAttributes[count];
+	                if (!media->IsSupported(attribute))
+	                    {
+	                    if ( KErrNone == GlxErrorManager::HasAttributeErrorL(media, iAttributes[count]) )
+	                        {
+	                        AddItemAttributeL(aAttributes, attribute);
+	                        attributesAdded = ETrue;
+	                        }
+	                    }
+	                }
+	            }
+	        }
+    	}
+
+    return attributesAdded;
+    }
+
+// -----------------------------------------------------------------------------
+// Add attribute to array, no duplicates
+// -----------------------------------------------------------------------------
+void CGlxAttributeContext::AddItemAttributeL(RArray<TMPXAttribute>& aAttributes, 
+        const TMPXAttribute& aAttribute) const
+    {
+    TRACER("CGlxAttributeContext::AddItemAttributeL");
+    
+    TIdentityRelation<TMPXAttribute> match(&TMPXAttribute::Match);
+    TInt index = aAttributes.Find(aAttribute, match);
+
+    if (index == KErrNotFound)
+        {
+        aAttributes.AppendL(aAttribute);
+        }
+    }
+
+// -----------------------------------------------------------------------------
+// -----------------------------------------------------------------------------
+// CGlxDefaultAttributeContext
+// -----------------------------------------------------------------------------
+// -----------------------------------------------------------------------------
+//
+
+// NewL
+// -----------------------------------------------------------------------------
+//
+EXPORT_C CGlxDefaultAttributeContext* CGlxDefaultAttributeContext::NewL()
+    {
+    TRACER("CGlxDefaultAttributeContext::NewL");
+    
+    CGlxDefaultAttributeContext* obj = new (ELeave) CGlxDefaultAttributeContext();
+    return obj;
+    }
+	
+// -----------------------------------------------------------------------------
+// Constructor
+// Sets the iterator of base class to be TGlxFromFocusOutwardIterator
+// -----------------------------------------------------------------------------
+//
+CGlxDefaultAttributeContext::CGlxDefaultAttributeContext() :
+        CGlxAttributeContext(&iFromFocusIterator)
+    {
+    }
+
+// -----------------------------------------------------------------------------
+// Destructor
+// -----------------------------------------------------------------------------
+//
+EXPORT_C CGlxDefaultAttributeContext::~CGlxDefaultAttributeContext()
+    {
+    TRACER("CGlxDefaultAttributeContext::Destructor");
+    
+    }
+
+// ----------------------------------------------------------------------------
+// Set range offsets
+// ----------------------------------------------------------------------------
+//
+EXPORT_C void CGlxDefaultAttributeContext::SetRangeOffsets(TInt aFrontOffset, TInt aRearOffset)
+    {
+    TRACER("CGlxDefaultAttributeContext::SetRangeOffsets");
+    
+    iFromFocusIterator.SetRangeOffsets(aRearOffset, aFrontOffset);
+    }