What I’ve learned when developing BlockAlertViews

What I’ve learned when developing

BlockAlertViews

Gustavo Ambrozio360iDev 2012

Tuesday, September 11, 12

http://www.thedevelopersconference.com.br/#descricao61






About me• Developing professionally since age of 15



• For iOS since the official SDK came out




• Did some apps and contracts as an independent developer in Brazil





• Writter for raywenderlich.com






• Hired by PocketGems to code games in SF






• Hired by PocketGems to code games in SF

• Hate engligh prepositions


What’s BlockAlertView






My love and hate story with UIAlertView

• (apparently) Easy to use • Delegates

• Switches

• Tags

• Constants


@interface MyViewController : UIViewController <UIAlertViewDelegate>

#define kRemoveConfirmAlertView 1#define kSendAlertView 2#define kLogoutConfirmAlertView 3

- (IBAction)sendItem:(id)sender{ UIAlertView *view = [[UIAlertView alloc] initWithTitle:@”Send to” message:@”Send message using:” delegate:self cancelButtonTitle:@”Cancel” otherButtonTitles:@”Twitter”, @”Facebook”, @”Email”, nil]; view.tag = kSendAlertView; [view show]; [view release];}














- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {

switch (alertView.tag){

case kRemoveConfirmAlertView:if (buttonIndex == 1)

[self removeItem];break;

case kSendAlertView:{

switch (buttonIndex){

case 0: // Cancelbreak;

case 1: // Twitter[self sendWith:kTwitter];break;

case 2: // Facebook[self sendWith:kFacebook];break;

case 3: // emailMFMailComposeViewController *view = [[MFMailComposeViewController alloc] init];view.mailComposeDelegate = self;[self.navigationController presentModalViewController:view animated:YES];break;

}}break;

}}












}}break;

}}












}}break;

}}












}}break;

}}












}}break;

}}












}}break;

}}


How blocks ended my hatred

• PSFoundation (https://github.com/steipete/PSFoundation/tree/master/Utils)

• Peter Steinberger


https://github.com/steipete/PSFoundation/tree/master/Utils




https://github.com/steipete











• PSAlertView e PSActionSheet

















• PSAlertView e PSActionSheet

• Renamed to BlockAlertView and BlockActionSheet
















- (IBAction)sendItem:(id)sender{ BlockAlertView *view = [BlocAlertView alertWithTitle:@”Send to” message:@”Send message using:”]; [view setCancelButtonWithTitle:@”Cancel” block:nil]; [view addButtonWithTitle:@”Twitter”, block:^{ [self sendWith:kTwitter]; }]; [view addButtonWithTitle:@”Facebook”, block:^{ [self sendWith:kFacebook]; }]; [view addButtonWithTitle:@”Email”, block:^{ MFMailComposeViewController *view = [[MFMailComposeViewController alloc] init];

view.mailComposeDelegate = self;[self.navigationController presentModalViewController:view animated:YES];

}]; view .tag = kSendAlertView; [view show];}




















- (IBAction)sendItem:(id)sender{ BlockAlertView *view = [BlockAlertView alertWithTitle:@”Send to” message:@”Send message using:”];

[view setCancelButtonWithTitle:@”Cancel” block:nil];

[view addButtonWithTitle:@”Twitter”, block:^{ [self sendWith:kTwitter]; }];

[view addButtonWithTitle:@”Facebook”, block:^{ [self sendWith:kFacebook]; }];

[view addButtonWithTitle:@”Email”, block:^{ MFMailComposeViewController *view = [[MFMailComposeViewController alloc] init];


}];

[view show];}






[view addButtonWithTitle:@”Email”, block:^{ MFMailComposeViewController *view = [[MFMailComposeViewController alloc] init];


}];

[view show];}


Lesson number 1

1. Use blocks instead of delegates (almost) all the time


Lesson number 1

1. Use blocks instead of delegates (almost) all the time

• Exception: When the block can retain something that can be deallocated before que block call gets made (NSURLConnections for example)


How to do it

1. Subclass the original class and have it conform with it’s delegate.

2. Create typedefs for all blocks

3. Create @property for all blocks with (copy)

4. Implement all init methods and set self as delegate.

5. Implement all delegates, create ivars for all and call them if not nil.


ARC compatibility

• Simple:

#if ! __has_feature(objc_arc)

#error This file must be compiled with ARC. Please add -fobjc-arc to the compiler flags of this file.

#endif

• Better:

Use Nick Lockwood’s ARC Helper .h file:

https://gist.github.com/1563325




Improving AVAudioPlayer

#import <Foundation/Foundation.h>#import <AVFoundation/AVFoundation.h>#import "ARCHelper.h"

typedef void (ÂudioPlayerDidFinishPlayingBlock)(BOOL);typedef void (ÂudioPlayerDecodeErrorDidOccurBlock)(NSError *);typedef void (ÂudioPlayerBeginInterruptionBlock)();typedef void (ÂudioPlayerEndInterruptionBlock)(NSUInteger);

@interface BlockAudioPlayer : AVAudioPlayer <AVAudioPlayerDelegate>

@property (nonatomic, copy) AudioPlayerDidFinishPlayingBlock audioPlayerDidFinishPlayingBlock;@property (nonatomic, copy) AudioPlayerDecodeErrorDidOccurBlock audioPlayerDecodeErrorDidOccurBlock;@property (nonatomic, copy) AudioPlayerBeginInterruptionBlock audioPlayerBeginInterruptionBlock;@property (nonatomic, copy) AudioPlayerEndInterruptionBlock audioPlayerEndInterruptionBlock;

@end


Improving AVAudioPlayer- (id)initWithContentsOfURL:(NSURL *)url error:(NSError **)outError{ self = [super initWithContentsOfURL:url error:outError]; if (self) { self.delegate = self; } return self;}

#pragma mark - AVAudioPlayerDelegate

- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag{ if (audioPlayerDidFinishPlayingBlock) audioPlayerDidFinishPlayingBlock(flag);}

https://github.com/gpambrozio/BlockAudioPlayer

Zachary Waldowski’s https://github.com/zwaldowski/BlocksKit




https://github.com/zwaldowski/BlocksKit

https://github.com/zwaldowski/BlocksKit

Hate comes back with a new face






A vision on how to end this hatred








Striking hatred with code





UIWindow

UView

UILabel

UIButton



UIWindow

UView

UILabel

UIButton



UIWindow

UView

UILabel

UIButton


Lesson number 2

2. UIWindow is an unkown obscure class that’s very rarely used (and with very poor documentation) but that might solve some tricky UI problems. Use with care.


UIWindow basics

• No hierarchy. UIWindow are ordered using their windowLevel:• UIWindowLevelNormal• UIWIndowLevelAlert• UIWindowLevelStatusBar

• If on the same level, ordered by creation time, last on top.

• makeKeyAndVisible can push it to the top, but still respecting windowLevel.


Key Window

• From the docs: “...window which is currently receiving keyboard events and other non touch-related events. Whereas touch events are delivered to the window in which the touch occurred, events that do not have an associated coordinate value are delivered to the key window of your application. Only one window at a time may be key."

• When you create a UIWindow and call makeKeyWindow, don’t just call resignKeyWindow. Save the previous keyWindow and call makeKeyWindow on it when you’re done.


Destroying hate


Lessons number 3 and 4

3. Open your mind to other libraries and don’t assume you need to do it the Apple way


Lessons number 3 and 4

3. Open your mind to other libraries and don’t assume you need to do it the Apple way

4. Don’t be lazy. It’s fun to implement something from scratch.


Spreading the love• BlockAlertView and BlockActionSheets are

open source

• github.com/gpambrozio/BlockAlertsAnd-ActionSheets


https://github.com/gpambrozio/BlockAlertsAnd-ActionSheets





open source


• blog.codecropper.com/2012/01/replicating-tweetbot-alerts-and-action-sheets/







open source


• blog.codecropper.com/2012/01/replicating-tweetbot-alerts-and-action-sheets/

• Improvements to UIAlertView and UIActionSheet






Spreading the love

• Import 6 files, 3 .h and 3 .m


Spreading the love


• Copy 1 .h file with UI attributes


Spreading the love



• Copy PNG assets or create your own


Spreading the love



• Copy PNG assets or create your own

• Change UI (optional)






[view setDestructiveButtonWithTitle:@”Delete”, block:^{ [self removeItem]; }];

[view show];}







[view show];}







[view show];}







[view show];}







[view show];}







[view show];}


Spreading the love


Spreading the love


Advanced love• Background and buttons and simple PNGs


Advanced love• It’s only an UIView....

[BlockBackgroundsharedInstance]

UIView


Advanced love• BlockTextPromptAlertView


Animated love


Animated love


Animated love


Animated love


Animated love


Animated love


Animated love


Lesson number 5

5. Opening your source is good: Improves your karma, your reputation and your source code.


Gustavo Ambrozio

• @gpambrozio

• blog.codecropper.com

• github.com/gpambrozio

• linkedin.com/in/gustavoambrozio


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2 apps in top 25 grossing apps


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What I’ve learned when developing BlockAlertViews