PaperFoldGallery displays multiple views in a paginated UIScrollView, but uses PaperFold library to animate to the next view.

PaperFoldGallery is used in the Walkthrough pages of Dispatch: Action-Based Email App.

The first level is a paginated UIScrollView that displays views in each page. The second level contains 2 PaperFold views that are folded/unfolded/hidden depending on the scroll view offset. These views show a folded screenshot of the views below it, and are hidden once the UIScrollView snaps to page.

The subviews can be any UIView subclasses, so it can be static view, or other views like UITableView.

The library takes a screenshot often to get the state of the view below it. If you are using static views, you can improve the unfolding performance by providing screenshots.

Initialize the gallery view

- (id)initWithFrame:(CGRect)frame folds:(int)folds

This value specifies the size of the frame

This value specifies number of folds

Reloads content in the gallery view

- (void)reloadData

Bounces the view to the left slightly to show the next fold on the right

- (void)bouncesToHintNextPage

Changes the current page

• (void)setPageNumber:(int)pageNumber animated:(BOOL)animated

This value specifies the page number to change to

This value specifies whether the page change should be animated

- (void)setPageNumber:(int)pageNumber animated:(BOOL)animated completed:(void(^)())block

This value specifies the page number to change to

This value specifies whether the page change should be animated

This block is called when the animation is complete

A non-optional method. Ask the delegate for cells at each page.

- (HCPaperFoldGalleryCellView*)paperFoldGalleryView:(HCPaperFoldGalleryView*)galleryView viewAtPageNumber:(int)pageNumber

The gallery view that requests for cell views

The page number requested

Notifies the delegate when page changes

- (void)paperFoldGalleryView:(HCPaperFoldGalleryView *)galleryView didScrollToPageNumber:(int)pageNumber;

The gallery view where the page change happens

The page number of the new page after scrolling

Requests dataSource for number if items to be displayed in the galleyView

- (NSInteger)numbeOfItemsInPaperFoldGalleryView:(HCPaperFoldGalleryView*)galleryView

The gallery view that will display the views

An optional method. Requests dataSource for UIImage to be displayed in the views' folds. If nil is returned, the library will take a screenshot automatically each time before folding. If a UIImage is returned, the library will use the image without taking screenshots (for better performance).

- (UIImage*)paperFoldGalleryView:(HCPaperFoldGalleryView*)galleryView imageAtPageNumber:(int)pageNumber

The gallery view that will display the views

The page number of the requested UIImage

This project uses ARC. If you are not using ARC in your project, add '-fobjc-arc' as a compiler flag for all the files in this project. XCode 4.4 is required for auto-synthesis.

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