/*
* 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: Window to a list of objects
*
*/
#include "glxlistwindow.h"
#include "glxpanic.h"
#include "glxlistutils.h" //for GlxListUtils
#include <glxtracer.h> //For logging
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// CGlxDataWindow
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
//
class CGlxDataWindow : public CBase
{
friend class TGlxWindowIterator;
public:
/** Destructor*/
~CGlxDataWindow()
{
iObjects.Close();
}
/** Destroy contents of the window */
void Destroy()
{
iObjects.ResetAndDestroy();
}
/** Reserve max window size */
inline void ReserveL( TInt aMaxCount )
{
iObjects.ReserveL( aMaxCount );
}
/** Preparet the window to accept items */
void InitializeL( const CGlxListWindow::TRange& aRange, TInt aTotalSize )
{
__TEST_INVARIANT;
iTotalSize = aTotalSize;
// use GlxListUtils::NormalizedIndex instead of Normalize to avoid
// execution-order dependency to the setting of iTotalSize
iWindowStartIndex = GlxListUtils::NormalizedIndex( aRange.iStartIndex, iTotalSize );
// all existing pointers in the array are NULL, as they have been
// set so by PopulateExistingAndUnuseOld
// add sufficient number of new null pointers
for ( TInt i = iObjects.Count(); i < aRange.iLength; i++ )
{
// Append cannot fail since reservation has been made
( void ) iObjects.AppendL( NULL );
}
// remove unnecessary pointers
for ( TInt i = iObjects.Count() - 1; i >= aRange.iLength; i-- )
{
iObjects.Remove( i );
}
__TEST_INVARIANT;
}
/** @return an iterator that can iterate throught the items in window */
inline TGlxWindowIterator Iterator() const
{
return TGlxWindowIterator( *this );
}
/** @return whether the list index is within range */
inline TBool InRange( TInt aListIndex ) const
{
return KErrNotFound != WindowIndex( aListIndex );
}
inline CBase*& operator[] ( TInt aListIndex )
{
return iObjects[ WindowIndex( aListIndex ) ];
}
/** @return the length of the window */
inline TInt Size() const
{
return iObjects.Count();
}
/** @return the total length of the list */
inline TInt TotalSize() const
{
return iTotalSize;
}
private:
/** convert a window index to list index */
TInt ListIndex( TInt aWindowIndex ) const
{
__ASSERT_DEBUG( aWindowIndex >= 0 && aWindowIndex < Size(), Panic( EGlxPanicIllegalArgument ) );
return Normalize( aWindowIndex + iWindowStartIndex );
}
/** convert a list index to window index */
/// @todo Make this private
TInt WindowIndex( TInt aListIndex ) const
{
if ( KErrNotFound == aListIndex )
{
return KErrNotFound;
}
__ASSERT_DEBUG( aListIndex >= 0 && aListIndex < iTotalSize, Panic( EGlxPanicIllegalArgument ) );
// Convert the list index to a window index
TInt windowIndex = Normalize( aListIndex - iWindowStartIndex );
if ( windowIndex >= Size() )
{
return KErrNotFound; // Does not fit to the window
}
return windowIndex;
}
/** Normalise index to list length */
inline TInt Normalize( TInt aIndex ) const
{
return GlxListUtils::NormalizedIndex( aIndex, iTotalSize );
}
/** Test state */
void __DbgTestInvariant() const
{
__ASSERT_DEBUG(iTotalSize >= 0 && iTotalSize < 50000, Panic(EGlxPanicIllegalState)); // Sanity check
__ASSERT_DEBUG(iObjects.Count() <= iTotalSize, Panic(EGlxPanicIllegalState));
}
private:
/// Full size of the list
TInt iTotalSize;
/// Index of the first object in iWindow in the list,
/// i.e., the list index from which the window starts from
TInt iWindowStartIndex;
/// List of objects in the window, starting from iWindowStartIndex
RPointerArray< CBase > iObjects;
};
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// Constructor
// -----------------------------------------------------------------------------
TGlxWindowIterator::TGlxWindowIterator( const CGlxDataWindow& aWindow )
{
TRACER("TGlxWindowIterator::TGlxWindowIterator");
iWindow = &aWindow;
iWindowIndex = 0;
}
// -----------------------------------------------------------------------------
// Constructor
// -----------------------------------------------------------------------------
EXPORT_C TGlxWindowIterator::TGlxWindowIterator( const TGlxWindowIterator& aIterator )
{
TRACER("TGlxWindowIterator::TGlxWindowIterator");
iWindow = aIterator.iWindow;
iWindowIndex = aIterator.iWindowIndex;
}
// -----------------------------------------------------------------------------
// ++
// -----------------------------------------------------------------------------
EXPORT_C TInt TGlxWindowIterator::operator++( TInt )
{
TRACER("TGlxWindowIterator::operator++");
if ( iWindowIndex == iWindow->iObjects.Count() )
{
return KErrNotFound;
}
return iWindow->ListIndex( iWindowIndex++ );
}
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// TChange
// -----------------------------------------------------------------------------
//
CGlxListWindow::TChange::TChange( TInt aNewFocusIndex, TInt aNewTotalSize, TChangeType aChangeType,
TInt aFirstChangedIndex, TInt aLastChangedIndex )
{
TRACER("TChange::Default Constructor");
iNewFocusIndex = aNewFocusIndex;
iNewTotalSize = aNewTotalSize;
iChangeType = aChangeType;
iFirstChangedIndex = aFirstChangedIndex;
iLastChangedIndex = aLastChangedIndex;
}
// -----------------------------------------------------------------------------
// Constructor
// -----------------------------------------------------------------------------
//
EXPORT_C CGlxListWindow::CGlxListWindow( MGlxWindowObjectFactory& aObjectFactory )
: iObjectFactory( aObjectFactory )
{
TRACER("CGlxListWindow::Default Constructor");
iFocusIndex = KErrNotFound; // No items, hence no focus
}
// -----------------------------------------------------------------------------
// ConstructL
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::ConstructL()
{
TRACER("CGlxListWindow::ConstructL");
iWorkingWindow = new (ELeave) CGlxDataWindow;
iWindow = new (ELeave) CGlxDataWindow;
// default range offsets are 0, 0, which means that only the focused item
// in in the window by default. Create an object for the focus. This
// makes it optional to call SetRangeOffsetsL if range remains 0,0
iUnusedObjects.AppendL( iObjectFactory.CreateObjectL() );
}
// -----------------------------------------------------------------------------
// Destructor
// -----------------------------------------------------------------------------
//
EXPORT_C CGlxListWindow::~CGlxListWindow()
{
TRACER("CGlxListWindow::Destructor");
// objects may exist in either iWindow or object pool (iUnusedObjects)
if ( iWindow )
{
// this call could be removed, if could call Cleanup here
// currently deriving classes implement CleanupObject, so calling it
// here is not possible => requires a different object as factory
iWindow->Destroy();
delete iWindow;
}
iUnusedObjects.ResetAndDestroy();
// the working window does not own anything
delete iWorkingWindow;
}
// -----------------------------------------------------------------------------
// Cleans up remaining objects in the window
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::CleanupL()
{
TRACER("CGlxListWindow::CleanupL");
// make the window empty. this will clean up all remaining objects.
UpdateL( TChange( KErrNotFound, 0, EChangeObjectsRemoved, 0, iWindow->TotalSize() - 1 ) );
}
// -----------------------------------------------------------------------------
// SetRangeOffsetsL
// -----------------------------------------------------------------------------
// DEPRECATED
EXPORT_C void CGlxListWindow::SetRangeOffsetsL( TInt aFrontOffset, TInt aRearOffset )
{
TRACER("CGlxListWindow::SetRangeOffsetsL");
SetRangeOffsetsL( iFocusIndex, iWindow->TotalSize(), aFrontOffset, aRearOffset );
}
// -----------------------------------------------------------------------------
// SetRangeOffsetsL
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::SetRangeOffsetsL( TInt aFocusIndex,
TInt aTotalSize, TInt aFrontOffset, TInt aRearOffset )
{
TRACER("CGlxListWindow::SetRangeOffsetsL");
__ASSERT_DEBUG( aFrontOffset <= 0 && aRearOffset >= 0, Panic( EGlxPanicIllegalArgument ) );
__ASSERT_DEBUG( ( 0 <= aFocusIndex && aFocusIndex < aTotalSize ) ||
( KErrNotFound == aFocusIndex && 0 == aTotalSize ),
Panic( EGlxPanicIllegalArgument ) );
iFrontOffset = aFrontOffset;
iRearOffset = aRearOffset;
// only ever expand the range. there is no use case to do the otherwise,
// so don't bother optimising that case by freeing unnecessary objects.
// all or no objects may be in use at any time - reserve max count in all arrays
TInt maxObjectCount = aRearOffset - aFrontOffset + 1;
iWorkingWindow->ReserveL( maxObjectCount );
iWindow->ReserveL( maxObjectCount );
iUnusedObjects.ReserveL( maxObjectCount );
// create enough new objects into the unused objects pool
// objects are either in the main window or in the pool
for ( TInt i = iWindow->Size() + iUnusedObjects.Count(); i < maxObjectCount; i++ )
{
// cannot fail since reservation made above
( void )iUnusedObjects.AppendL( iObjectFactory.CreateObjectL() );
}
UpdateL( TChange( aFocusIndex, aTotalSize, EChangeNone, 0, 0 ) );
}
// -----------------------------------------------------------------------------
// Iterator
// -----------------------------------------------------------------------------
//
EXPORT_C TGlxWindowIterator CGlxListWindow::Iterator() const
{
TRACER("CGlxListWindow::Iterator");
return iWindow->Iterator();
}
// -----------------------------------------------------------------------------
// SetFocusIndexL
// -----------------------------------------------------------------------------
// DEPRICATED
EXPORT_C void CGlxListWindow::SetFocusIndexL( TInt aFocusIndex )
{
TRACER("CGlxListWindow::SetFocusIndexL");
SetFocusIndexL( aFocusIndex, iWindow->TotalSize() );
}
// -----------------------------------------------------------------------------
// SetFocusIndexL
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::SetFocusIndexL( TInt aFocusIndex, TInt aTotalSize )
{
TRACER("CGlxListWindow::SetFocusIndexL");
__ASSERT_DEBUG( ( 0 <= aFocusIndex && aFocusIndex < aTotalSize ) ||
( KErrNotFound == aFocusIndex && 0 == aTotalSize ),
Panic( EGlxPanicIllegalArgument ) );
__TEST_INVARIANT;
UpdateL( TChange( aFocusIndex, aTotalSize, EChangeNone, 0, 0 ) );
__TEST_INVARIANT;
}
// -----------------------------------------------------------------------------
// AddObjectsL
// -----------------------------------------------------------------------------
// DEPRICATED
EXPORT_C void CGlxListWindow::AddObjectsL( TInt aFirstNewIndex, TInt aLastNewIndex )
{
TRACER("CGlxListWindow::AddObjectsL");
TInt newItemCount = aLastNewIndex - aFirstNewIndex + 1;
TInt newTotalSize = iWindow->TotalSize() + newItemCount;
// Check if it is necessary to move focus
TInt newFocusIndex = iFocusIndex;
if ( KErrNotFound == newFocusIndex )
{
// List is empty, so set focus to the first item
__ASSERT_DEBUG(iWindow->TotalSize() == 0, Panic(EGlxPanicIllegalState)); // Must have had an empty list to have no focus
newFocusIndex = 0;
}
else if (newFocusIndex >= aFirstNewIndex)
{
// Move focus, so that the focus stays on the same item that was
// focused before items were added
newFocusIndex += newItemCount;
}
AddObjectsL( newFocusIndex, newTotalSize, aFirstNewIndex, aLastNewIndex );
}
// -----------------------------------------------------------------------------
// AddObjectsL
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::AddObjectsL( TInt aFocusIndex,
TInt aTotalSize, TInt aFirstNewIndex, TInt aLastNewIndex )
{
TRACER("CGlxListWindow::AddObjectsL");
__ASSERT_DEBUG( 0 <= aFirstNewIndex && aFirstNewIndex <= aLastNewIndex &&
aLastNewIndex < aTotalSize &&
0 <= aFocusIndex && aFocusIndex < aTotalSize,
Panic( EGlxPanicIllegalArgument ) );
__TEST_INVARIANT;
UpdateL( TChange( aFocusIndex, aTotalSize, EChangeObjectsAdded,
aFirstNewIndex, aLastNewIndex ) );
__TEST_INVARIANT;
}
// -----------------------------------------------------------------------------
// RemoveObjectsL
// -----------------------------------------------------------------------------
// DEPRICATED
EXPORT_C void CGlxListWindow::RemoveObjectsL( TInt aFirstRemovedIndex, TInt aLastRemovedIndex )
{
TRACER("CGlxListWindow::RemoveObjectsL");
TInt itemsRemovedCount = aLastRemovedIndex - aFirstRemovedIndex + 1;
TInt newTotalSize = iWindow->TotalSize() - itemsRemovedCount;
TInt newFocusIndex = iFocusIndex;
// check number of items left
if (newTotalSize == 0)
{
// all items have been removed
newFocusIndex = KErrNotFound;
}
else // still some items in the list
{
// Focus should stay on the same item if possible. If not, it should
// go to the first previous item still existing. If none, it should go to
// first (=first next) item.
// @todo: Do not maintain focus index in this class, This is broken
// Update focus if the removal point was before the focus
if (aFirstRemovedIndex <= newFocusIndex)
{
TInt firstToFocusCount = newFocusIndex - aFirstRemovedIndex + 1;
newFocusIndex -= Min(itemsRemovedCount, firstToFocusCount);
if (newFocusIndex < 0)
{
newFocusIndex = 0;
}
}
}
RemoveObjectsL( newFocusIndex, newTotalSize, aFirstRemovedIndex, aLastRemovedIndex );
}
// -----------------------------------------------------------------------------
// RemoveObjectsL
// -----------------------------------------------------------------------------
//
EXPORT_C void CGlxListWindow::RemoveObjectsL( TInt aFocusIndex,
TInt aTotalSize, TInt aFirstRemovedIndex, TInt aLastRemovedIndex )
{
TRACER("CGlxListWindow::RemoveObjectsL");
__ASSERT_DEBUG( 0 <= aFirstRemovedIndex && aFirstRemovedIndex <= aLastRemovedIndex &&
( ( 0 <= aFocusIndex && aFocusIndex < aTotalSize ) ||
( KErrNotFound == aFocusIndex && aTotalSize == 0 ) ),
Panic( EGlxPanicIllegalArgument ) );
__TEST_INVARIANT;
UpdateL( TChange( aFocusIndex, aTotalSize, EChangeObjectsRemoved,
aFirstRemovedIndex, aLastRemovedIndex ) );
__TEST_INVARIANT;
}
// -----------------------------------------------------------------------------
// UpdateL
// -----------------------------------------------------------------------------
//
void CGlxListWindow::UpdateL( const TChange& aChange )
{
TRACER("CGlxListWindow::UpdateL");
// (in a list of: |abcdefghijklm|
// iWindow: |----efghi----|
// iWorkingWindow: undefined state
// iUnusedObjects: XXX (3 objects, in reality only contains objects if list
// is shorter than max window length)
// Prepare the working window to accept objects
iWorkingWindow->InitializeL( Range( aChange ), aChange.iNewTotalSize );
// iWindow: |----efghi----|
// iWorkingWindow: |------00000--|
// iUnusedObjects: XXX
// move unused objects to pool, and reusable objects to working window
PopulateExistingAndUnuseOldL( aChange );
// iWindow: |----efghi----|
// iWorkingWindow: |------ghi00--|
// iUnusedObjects: XXXXX (2 objects added, used to be e and f)
// set the current window to working window and vice versa.
// do this before populating new items, since when the deriving class
// is asked to set up the items, it is better to allow it to access the
// objects from the window (only objects from main window can be accessed
// externally)
SwapWindows();
iFocusIndex = aChange.iNewFocusIndex;
// iWindow: |------ghi00--|
// iWorkingWindow: |----xxxxx----| = undefined
// iUnusedObjects: XXXXX
// populate objects in working window that did not exist in current window
PopulateNew();
// iWindow: |------ghijk--|
// iWorkingWindow: |----xxxxx----| = undefined
// iUnusedObjects: XXX (2 objects moved to iWindow)
}
// -----------------------------------------------------------------------------
// PopulateExistingAndUnuseOldL
// -----------------------------------------------------------------------------
//
void CGlxListWindow::PopulateExistingAndUnuseOldL( const TChange& aChange )
{
TRACER("CGlxListWindow::PopulateExistingAndUnuseOldL");
// move objects that are needed after the change into the working window,
// and objects that are not needed into the object pool
TGlxWindowIterator currentWindowIterator = iWindow->Iterator();
TInt index = 0;
while ( KErrNotFound != ( index = currentWindowIterator++ ) )
{
// translate to what the list index would be after the change.
TInt indexAfterChange = IndexAfterChange( index, aChange );
// item is needed in the new window if it is in the range of the new window
if ( iWorkingWindow->InRange( indexAfterChange ) )
{
// move the object from the current window to the working window
( *iWorkingWindow )[ indexAfterChange ] = ( *iWindow )[ index ];
}
else
{
// ask deriving class to clean up the object (free resources, etc).
// do this first, so that the deriving class can access the window
// by index, if needed
iObjectFactory.CleanupObject( index, *( *iWindow )[ index ] );
// add the object to the unused objects pool
// cannot fail since reservation made
( void )iUnusedObjects.AppendL( ( *iWindow )[ index ] );
}
// clear the pointer in the existing window. it is not strictly necessary
// to do here, but saves a loop from doing it in CGlxDataWindow::InitializeL
( *iWindow )[ index ] = NULL;
}
}
// -----------------------------------------------------------------------------
// Populate objects that were not reused
// -----------------------------------------------------------------------------
//
void CGlxListWindow::PopulateNew()
{
TRACER("CGlxListWindow::PopulateNew");
// iWindow is now partially constructed
// populate all pointers that are null
TGlxWindowIterator newWindowIterator = iWindow->Iterator();
TInt index = 0;
while ( KErrNotFound != ( index = newWindowIterator++ ) )
{
if ( NULL == ( *iWindow )[ index ] )
{
CBase* object = UnusedObject();
( *iWindow )[ index ] = object;
// configure the object
iObjectFactory.SetupObject( index, *object );
}
}
}
// -----------------------------------------------------------------------------
// Reuse
// -----------------------------------------------------------------------------
//
void CGlxListWindow::SwapWindows()
{
TRACER("CGlxListWindow::SwapWindows");
CGlxDataWindow* temp = iWorkingWindow;
iWorkingWindow = iWindow;
iWindow = temp;
}
// -----------------------------------------------------------------------------
// Return an object from the pool, and remove it from the pool
// -----------------------------------------------------------------------------
//
CBase* CGlxListWindow::UnusedObject()
{
TRACER("CGlxListWindow::UnusedObject");
TInt lastObjectIndex = iUnusedObjects.Count() - 1;
CBase* object = iUnusedObjects[ lastObjectIndex ];
iUnusedObjects.Remove( lastObjectIndex );
return object;
}
// -----------------------------------------------------------------------------
// Access object by index
// -----------------------------------------------------------------------------
//
EXPORT_C CBase* CGlxListWindow::At( TInt aIndex )
{
TRACER("CGlxListWindow::At");
if ( iWindow->InRange( aIndex ) )
{
return ( *iWindow )[ aIndex ];
}
return NULL;
}
// -----------------------------------------------------------------------------
// Access object by index
// -----------------------------------------------------------------------------
//
EXPORT_C const CBase* CGlxListWindow::At( TInt aIndex ) const
{
TRACER("CGlxListWindow::At");
return const_cast< CGlxListWindow* >( this )->At( aIndex );
}
// -----------------------------------------------------------------------------
// Range
// -----------------------------------------------------------------------------
//
CGlxListWindow::TRange CGlxListWindow::Range( const TChange& aChange ) const
{
TRACER("CGlxListWindow::Range");
TRange range;
range.iLength = iRearOffset - iFrontOffset + 1; // Add 1 for focus
// Start index is always zero if the whole list fits into the window
if ( range.iLength >= aChange.iNewTotalSize )
{
// All items are within range
range.iStartIndex = 0;
range.iLength = aChange.iNewTotalSize;
}
else
{
// Not all items in the list fit within the range
range.iStartIndex = GlxListUtils::NormalizedIndex(
aChange.iNewFocusIndex + iFrontOffset, aChange.iNewTotalSize );
// check that ranges don't ever meet at the other side of the loop
__ASSERT_DEBUG( range.iStartIndex != GlxListUtils::NormalizedIndex( range.iStartIndex + range.iLength, aChange.iNewTotalSize )
|| ( iFrontOffset == 0 && iRearOffset == 0 ), Panic( EGlxPanicLogicError ) );
}
return range;
}
// -----------------------------------------------------------------------------
// Convert a list index to a list index in a changed list
// -----------------------------------------------------------------------------
//
TInt CGlxListWindow::IndexAfterChange( TInt aIndex,
const TChange& aChange ) const
{
TRACER("CGlxListWindow::IndexAfterChange");
// Convert the new list index into an old list index
TInt changeCount = aChange.iLastChangedIndex - aChange.iFirstChangedIndex + 1;
TInt indexAfterChange = aIndex;
if ( aChange.iFirstChangedIndex <= aIndex )
{
if ( aChange.iChangeType == EChangeObjectsRemoved )
{
// f l (first, last)
// old: |---NNN---||||||------|
// new: |------||||||------|
// If the index is between the indexes, the change will remove it
if ( aIndex <= aChange.iLastChangedIndex )
{
// The index is one of the new items. It does not exist in the old window
indexAfterChange = KErrNotFound;
}
else
{
// The index is after the items that will be removed. Adjust the index by "removing" the items.
indexAfterChange -= changeCount;
}
}
else if ( aChange.iChangeType == EChangeObjectsAdded )
{
// Adjust the index by "adding" the items before the index
// old: |------||||||------|
// new: |---NNN---||||||------|
// f l (first, last)
indexAfterChange += changeCount;
}
// if EChangeNone, no adjustment needed
}
// else no adjustment need, since the change happened after the index
return indexAfterChange;
}
// ---------------------------------------------------------------------------
// Test invariant
// ---------------------------------------------------------------------------
EXPORT_C void CGlxListWindow::__DbgTestInvariant() const
{
TRACER("CGlxListWindow::__DbgTestInvariant");
__ASSERT_DEBUG( ( iFocusIndex >= 0 && iFocusIndex < iWindow->TotalSize() ) ||
( KErrNotFound == iFocusIndex && 0 == iWindow->TotalSize() ),
Panic( EGlxPanicIllegalState ) );
__ASSERT_DEBUG( iFrontOffset <= 0 && iRearOffset >= 0, Panic( EGlxPanicIllegalState ) );
}