TANSTAAFL: using open source iPhone UI

codeJonathan Saggau (@jonmarimba)

Sounds Broken inc

Da book

The dude

Three20 image viewer

Apple Joe++

Three20 image viewer

Apple Joe++

Demoor... Julia Child impression

How to use three20 photo views

Static Library; pay special attention to linker flags on web site.

<TTPhotoSource> conforming object, which vends: <TTPhoto> conforming objects

Note: <TTModel, TTURLObject>

Um. What?

/** * TTModel describes the state of an object that can be loaded from a remote source. * * By implementing this protocol, you can communicate to the user the state of network * activity in an object. */@protocol TTModel <NSObject>

/** * An array of objects that conform to the TTModelDelegate protocol. */- (NSMutableArray*)delegates;

/** * Indicates that the data has been loaded. * * Default implementation returns YES. */- (BOOL)isLoaded;

/** * Indicates that the data is in the process of loading. * * Default implementation returns NO. */- (BOOL)isLoading;

/** * Indicates that the data is in the process of loading additional data. * * Default implementation returns NO. */- (BOOL)isLoadingMore;

/** * Indicates that the model is of date and should be reloaded as soon as possible. * * Default implementation returns NO. */-(BOOL)isOutdated;

/** * Loads the model. * * Default implementation does nothing. */- (void)load:(TTURLRequestCachePolicy)cachePolicy more:(BOOL)more;

/** * Cancels a load that is in progress. * * Default implementation does nothing. */- (void)cancel;

/** * Invalidates data stored in the cache or optionally erases it. * * Default implementation does nothing. */- (void)invalidate:(BOOL)erase;

@end

@protocol TTURLObject <NSObject>@optional

/** * Converts the object to a URL using TTURLMap. */@property (nonatomic, readonly) NSString* URLValue;

/** * Converts the object to a specially-named URL using TTURLMap. */- (NSString*)URLValueWithName:(NSString*)name;

@end

How it works

TTPhotoViewController and TTThumbsViewController

TTURLCache caches images to memory and / or disk

TTURLRequestQueue handles downloading images

@protocol TTPhotoSource <TTModel, TTURLObject>

/** * The title of this collection of photos. */@property (nonatomic, copy) NSString* title;

/** * The total number of photos in the source, independent of the number that have been loaded. */@property (nonatomic, readonly) NSInteger numberOfPhotos;

/** * The maximum index of photos that have already been loaded. */@property (nonatomic, readonly) NSInteger maxPhotoIndex;

/** * */- (id<TTPhoto>)photoAtIndex:(NSInteger)index;

@end

@protocol TTPhoto <NSObject, TTURLObject>

/** * The photo source that the photo belongs to. */@property (nonatomic, assign) id<TTPhotoSource> photoSource;

/** * The index of the photo within its photo source. */@property (nonatomic) CGSize size;

/** * The index of the photo within its photo source. */@property (nonatomic) NSInteger index;

/** * The caption of the photo. */@property (nonatomic, copy) NSString* caption;

/** * Gets the URL of one of the differently sized versions of the photo. */- (NSString*)URLForVersion:(TTPhotoVersion)version;

@end

can use bundle://someImageFileNameHere as URL string to load images from app bundle

can use documents://someImageFileNameHere as URL string to load images from user documents folder

Other cool stuff about three20

URL-based navigation that can persist the path taken to get to a given view controller and can push that stack of

views back on when the user re-opens your app.

Stylesheets to “skin” your app easily.

Pretty buttons and overlays.

Decent (visual) error handling for cloud-based apps

Simpler UITableView programming using TTModel*

Documentation and help

Mailing list: http://groups.google.com/group/three20

API docs: http://three20.info/

Me! jonathan@jonathansaggau.com @jonmarimba

(I’m not affiliated with three20, I just use it a lot)

Calendar view with Kal

Apple Keith

@protocol KalDataSourceCallbacks;

@protocol KalDataSource <NSObject, UITableViewDataSource>- (void)presentingDatesFrom:(NSDate *)fromDate to:(NSDate *)toDate delegate: (id<KalDataSourceCallbacks>)delegate;- (NSArray *)markedDatesFrom:(NSDate *)fromDate to:(NSDate *)toDate;- (void)loadItemsFromDate:(NSDate *)fromDate toDate:(NSDate *)toDate;- (void)removeAllItems;@end

@protocol KalDataSourceCallbacks <NSObject>- (void)loadedDataSource:(id<KalDataSource>)dataSource;@end

Coverflow view with OpenFlow

Apple Alex

Demoor... Julia Child impression

How to use it.@protocol AFOpenFlowViewDataSource <NSObject>

//Tells the data source that will need this image. //The data source should set the image as soon as it’s ready- (void)openFlowView:(AFOpenFlowView *)openFlowView requestImageForIndex:(int)index;- (UIImage *)defaultImage;

@end

//Allows the delegate to update other parts of UI for selection@protocol AFOpenFlowViewDelegate <NSObject>@optional- (void)openFlowView:(AFOpenFlowView *)openFlowView selectionDidChange:(int)index;@end

How to use it.

[(AFOpenFlowView *)someView setImage:someImage forIndex:someInteger];

BTW: The sample code also has a useful image loading subclass of NSOperation.

If you want to change the image for a given index, do this:

How it works

// Set some perspective CATransform3D sublayerTransform = CATransform3DIdentity; sublayerTransform.m34 = -0.01; // 1 / -zDistance where zDistance = 100 [scrollView.layer setSublayerTransform:sublayerTransform];

CoreAnimation 2.5D++

Dequeues images much like the UITableView (and the TTPhotoview controller, too)

Draws only those images that are on screen

// the magic is here- (void)layoutCover:(AFItemView *)aCover selectedCover:(int)selectedIndex animated:(Boolean)animated

Beware The Uncanny Valley.

Wikipedia User:Smurrayinchester (Creative Commons Attribution ShareAlike 3.0)

Coverflow view with OpenFlow

Apple Alex

What needs a-changin’The animation is a little “off” for the rotation (seems like

it’s the wrong speed)

The z position of the flanking photos is not far enough away.

Feels like there is a lot of friction.

The reflection under the covers is semi-transparent. Apple’s view has the reflected images occlude those

behind as in “real life.”

How I “fixed” it.

Let a scroll view do the animating left to right and set which page is selected (and therefore rotated to face the

user) based on screen centerline.

Hacking others’ code is fun (really)

// UIScrollViewDecelerationRateNormal = 0.998// UIScrollViewDecelerationRateFast = 0.990self.decelerationRate = .992;

How I “fixed” it.scrolling a UIScrollView sets bounds constantly

and calls layoutSubviews a lot...- (void)layoutSubviews{ NSLog(@"[%@ %s]", self, _cmd); halfScreenWidth = self.bounds.size.width / 2; halfScreenHeight = self.bounds.size.height / 2; int lowerBound = MAX(-1, selectedCoverView.number - COVER_BUFFER); int upperBound = MIN(self.numberOfImages - 1, selectedCoverView.number + COVER_BUFFER); [self layoutCovers:selectedCoverView.number fromCover:lowerBound toCover:upperBound]; [self setNumberOfImages:numberOfImages]; // resets view bounds and stuff CGPoint contentOffset = [self contentOffset]; int targetCover = (int) roundf(contentOffset.x / COVER_SPACING); if (targetCover != selectedCoverView.number) { if (targetCover < 0) [self setSelectedCover:0]; else if (targetCover >= self.numberOfImages) [self setSelectedCover:self.numberOfImages - 1]; else [self setSelectedCover:targetCover]; }}

// 1 / -zDistance where zDistance = 100

- (SBNotifyingWindow *)appWindow{ id appDel = [[UIApplication sharedApplication] delegate]; if([appDel respondsToSelector:@selector(window)]) { UIWindow *window = [appDel performSelector:@selector(window)]; if([window isMemberOfClass:[SBNotifyingWindow class]]) { return (SBNotifyingWindow *)window; } } return nil;}

- (void)setUpInitialState { [[self appWindow] addObjectInterestedInTouches:self];

Hijacking touch eventsI think I stole this from Apple’s sample code

#pragma mark SBNotifyingWindowTouches

-(void)interestingEvent:(UIEvent *)event;{ //NSLog(@"%@ %s %@", self, _cmd, event); NSSet *touches = [event allTouches]; UITouch *touch = [touches anyObject]; UITouchPhase phase = [touch phase]; if (phase == UITouchPhaseBegan) { [self touchesBegan:touches withEvent:event]; } if (phase == UITouchPhaseEnded) { [self touchesEnded:touches withEvent:event]; } if (phase == UITouchPhaseCancelled) { [self touchesCancelled:touches withEvent:event]; } if (phase == UITouchPhaseMoved) { [self touchesMoved:touches withEvent:event]; }}

Coverflow view with OpenFlow

Apple Alex

Coverflow view with OpenFlow

AppleMy mods of Alex’s

awesome code (ongoing)

Demoor... Julia Child impression

To Do

The center view doesn’t quite center after you throw the view around. (UIScrollview’s friction stops where it wants to)

Would like to add flipping the front cover to another view and add the rest of the UI in Apple’s implementation.

My mods are available on github at:https://github.com/jonmarimba/OpenFlow

Other implementations

FlowCover (OpenGL ES)

Plausible Labs has one, too (Not free, but very accurate)

Look for gogoDocs Google Docs reader for iPhone and iPad. It’s in an

the app store in your pocket.

jonathan@jonathansaggau.comhttp://jonathansaggau.com/blog

twit: @jonmarimba

jonathan@jonathansaggau.comhttp://jonathansaggau.com/blog

twit: @jonmarimba

Nerds for hire // Hiring nerds

Will Code for food.Will, um, food for code.