PaperFoldGallery
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.
How it works
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.
Usage
HCPaperFoldGalleryView
initWithFrame:folds:
Initialize the gallery view
- (id)initWithFrame:(CGRect)frame folds:(int)folds
Parameters
frame
This value specifies the size of the frame
folds
This value specifies number of folds
reloadData
Reloads content in the gallery view
- (void)reloadData
bouncesToHintNextPage
Bounces the view to the left slightly to show the next fold on the right
- (void)bouncesToHintNextPage
setPageNumber:animated:
Changes the current page
- (void)setPageNumber:(int)pageNumber animated:(BOOL)animated
Parameters
pageNumber
This value specifies the page number to change to
animated
This value specifies whether the page change should be animated
setPageNumber:animated:completed:
- (void)setPageNumber:(int)pageNumber animated:(BOOL)animated completed:(void(^)())block
Parameters
pageNumber
This value specifies the page number to change to
animated
This value specifies whether the page change should be animated
block
This block is called when the animation is complete
HCPaperFoldGalleryViewDelegate
paperFoldGalleryView:viewAtPageNumber:
A non-optional method. Ask the delegate for cells at each page.
- (HCPaperFoldGalleryCellView*)paperFoldGalleryView:(HCPaperFoldGalleryView*)galleryView viewAtPageNumber:(int)pageNumber
Parameters
galleryView
The gallery view that requests for cell views
pageNumber
The page number requested
paperFoldGalleryView:didScrollToPageNumber:
Notifies the delegate when page changes
- (void)paperFoldGalleryView:(HCPaperFoldGalleryView *)galleryView didScrollToPageNumber:(int)pageNumber;
Parameters
galleryView
The gallery view where the page change happens
pageNumber
The page number of the new page after scrolling
HCPaperFoldGalleryViewDatasource
numbeOfItemsInPaperFoldGalleryView:
Requests dataSource for number if items to be displayed in the galleyView
- (NSInteger)numbeOfItemsInPaperFoldGalleryView:(HCPaperFoldGalleryView*)galleryView
Parameters
galleryView
The gallery view that will display the views
paperFoldGalleryView:imageAtPageNumber:
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
Parameters
galleryView
The gallery view that will display the views
pageNumber
The page number of the requested UIImage
Requirements
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.