layoutAttributesForSupplementaryItemInSection called too often

[allright]

Have to optimize
JNWCollectionViewFramework:layoutIdentifiersForSupplementaryViewsInRect:(CGRect)rect{
}
to call layoutAttributesForSupplementaryItemInSection only for visible sections
Test case: a table with 1000 sections - may be not smooth.

I will try to fix...

[jwilling]

Ah yes, I perform a linear search and get the layout attributes for each supplementary item to see if it intersects the visible rect. This should probably be deferred to the layout as well, as it does for the cells already.

[allright]

Also I've just figured out that:
recursive call of
JNWCollectionViewLayoutAttributes *nextHeaderAttributes = [self layoutAttributesForSupplementaryItemInSection:sectionIdx + 1 kind:kind];
cause too big call stack.

[allright]

NSOrderedSet

• (NSUInteger)indexOfObject:(id)object inSortedRange:(NSRange)range options:(NSBinarySearchingOptions)opts usingComparator:(NSComparator)cmp; // binary search

can replace linear search by binary

[jwilling]

@allright I can't assume the layout is going to be linear (in which case a binary search would be fine), so I have to fallback to a linear search. That's why I suggested it be deferred to the layout class, as it's already done in for the cells. I use a binary search already for the cells in the list view.

Do the lag issues go away when you switch off sticky headers? I didn't test the sticky header code with a large number of sections, and that code would be badly optimized in that case. If you have any better ideas for implementation I'm all ears.

[allright]

I have to dig into the code a little deeper to generate idea...

[jwilling]

Closing this issue in favor of #108.