Notes of a Developer » iPad

Эксперемент

Vladimir Boychentsov — Sun, 13 Jun 2010 18:54:48 +0000

Написал простенькую программку ради эксперимента. С помощью программы можно ходит по корневому разделу системы, без Jailbreak. Если кто-то имеет опыт как создать фаил в директории не принадлежащей программе, без взлома устройства, и поделится! Буду очень признателен!

И собственно сам код

UIImage and Memory

Vladimir Boychentsov — Thu, 10 Jun 2010 11:43:22 +0000

+[UIImage imageNamed:]
• Reads the ﬁle, uncompresses it, caches result
• Cached copy of data is kept even if the UIImage is deallocated
• Low memory condition causes cache to be purged.
• No direct control over when cache is purged.
• Use for small frequently drawn images.

+[UIImage imageWithContentsOfFile:]
• Just reads enough of ﬁle to determine if it can open the ﬁle.
• Reads and uncompresses the ﬁle each time it draws. Uses uncompressed size worth of memory only temporarily.
• Assigning a UIImage created this way to a UIImageView or as the contents of a CALayer also causes it to read and uncompress the ﬁle. The UIImageView or CALayer keep the expanded version.

Memory Usage (in MB) 8.6 MB image used with UIImageView

	imageNamed	imageWithContentsofFile
Initial	2.46	2.46
Load UIImage	11.12	2.51
Assign to UIImageView	11.09	11.09
Remove from UIImageView	11.12	2.51

Memory Usage (in MB) 8.6 MB image used with UIView subclass (stored in instance variable and drawn with drawinRect: )

	imageNamed	imageWithContentsofFile
Initial	2.73	2.73
Load UIImage	11.38	2.78
Assign to UIImageView	11.81	3.20
Remove from UIImageView	11.84	3.04

Спасибо за некоторые пояснения Андрею Копаневу :)

И вот этому документу – Robert Clair

iPhone 3D Samples from “iPhone 3D Programming” book

Vladimir Boychentsov — Wed, 09 Jun 2010 13:35:34 +0000

iPhone 3D Samples from “iPhone 3D Programming Developing Graphical Applications with OpenGL ES” book.
Thanks Frank and Doris Rideout and O’REILLY

31 iPhone 3D Samples OpenGL ES 1.1 and 2.0

All links direct to http://examples.oreilly.com/

All Samples

HelloArrow

HelloCone

TouchCone

ModelViewer.SimpleWireframe

ModelViewer.VertexLighting

ModelViewer.PixelLighting

ModelViewer.ToonLighting

ModelViewer.FancyWireframe

ModelViewer.ObjViewer

ModelViewer.Textured

TextureFilters

TextureFormats

CameraTexture

TextureAlpha

Trefoil.Stencil

Trefoil.FakeStencil

Trefoil.Antialiasing

Trefoil.Jitter

AaLines

Holodeck.Clouds

Holodeck.Camera

Klein.Fps

Haiku

DistanceField

SpriteSheet

SpringyStars

Klein.Bumpy

Klein.Cubemap

CrudeBloom

GaussianBloom

VertexSkinning

Good book!

Vladimir Boychentsov — Tue, 08 Jun 2010 21:04:05 +0000

Do you have a great idea for a graphics-intensive iPhone or iPad application, but don’t know how to bring it to life? This book offers the perfect solution: a crash course on the OpenGL graphics library with an overview of iPhone 3D development. Whether you’re an experienced OpenGL developer looking to build iPhone apps for the first time, or an iPhone developer wanting to learn sophisticated graphics, iPhone 3D Programming addresses both in one concise, easy-to-use guide.

What does it take to build an iPhone app with stunning 3D graphics? This book will show you how to apply OpenGL graphics programming techniques to any device running the iPhone OS — including the iPad and iPod Touch — with no iPhone development or 3D graphics experience required. iPhone 3D Programming provides clear step-by-step instructions, as well as lots of practical advice, for using the iPhone SDK and OpenGL.

You’ll build several graphics programs — progressing from simple to more complex examples — that focus on lighting, textures, blending, augmented reality, optimization for performance and speed, and much more. All you need to get started is a solid understanding of C++ and a great idea for an app.

* Learn fundamental graphics concepts, including transformation matrices, quaternions, and more
* Get set up for iPhone development with the Xcode environment
* Become familiar with versions 1.1 and 2.0 of the OpenGL ES API, and learn to use vertex buffer objects, lighting, texturing, and shaders
* Use the iPhone’s touch screen, compass, and accelerometer to build interactivity into graphics applications
* Build iPhone graphics applications such as a 3D wireframe viewer, a simple augmented reality application, a spring system simulation, and more

This book received valuable community input through O’Reilly’s Open Feedback Publishing System (OFPS). Learn more at

Buy Book

Free for online read

купил iPad :)

Vladimir Boychentsov — Sun, 06 Jun 2010 15:26:14 +0000

Как вы уже поняли речь пойдет про iPad :) Девайс удобный и очень впечетляющий, но все же напоминает большой айпод тач. Огорчает отсутствие камеры. В целом ничего особенного, беру его в руки в основном когда нужно работать или почитать письма и посерфить немного.

На последней фотографии видно как отлично можно использовать устройство для презентаций. Этот пост я писал с iPad, не очень удобно, думаю будет удобнее если подсоединить клавиатуру.

Make gradient on iPhone/iPad

Vladimir Boychentsov — Sun, 30 May 2010 18:57:09 +0000

It’s easy! As of iPhone SDK 3.0, custom gradients can be implemented very easily, without subclassing or images, by using the new CAGradientLayer

add framework

#import < QuartzCore/QuartzCore.h>

so, example:

UIView *myTabView = [[UIView alloc] initWithFrame:frame];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = myTabView.bounds;
gradient.colors = [NSArray arrayWithObjects:
(id)[[UIColor colorWithRed:0.1 green:0.1 blue:0.1 alpha:0.8 ] CGColor]
, (id)[[UIColor colorWithRed:0.1 green:0.1 blue:0.1 alpha:0.8 ] CGColor]
, (id)[[UIColor colorWithRed:0.1 green:0.1 blue:0.1 alpha:0.8 ] CGColor]
, (id)[[UIColor blackColor] CGColor]
, (id)[[UIColor blackColor] CGColor], nil];
[myTabView.layer insertSublayer:gradient atIndex:0];
[[self.tabBarController tabBar] insertSubview:myTabView atIndex:0];
[myTabView release];

Result:

or, nice example with use Core Graphics to draw the gradient

- (void)drawRect:(CGRect)rect
{
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CGGradientRef glossGradient;
CGColorSpaceRef rgbColorspace;
size_t num_locations = 2;
CGFloat locations[2] = { 0.0, 1.0 };
CGFloat components[8] = { 1.0, 1.0, 1.0, 0.35, // Start color
1.0, 1.0, 1.0, 0.06 }; // End color
rgbColorspace = CGColorSpaceCreateDeviceRGB();
glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, components, locations, num_locations);
CGRect currentBounds = self.bounds;
CGPoint topCenter = CGPointMake(CGRectGetMidX(currentBounds), 0.0f);
CGPoint midCenter = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMidY(currentBounds));
CGContextDrawLinearGradient(currentContext, glossGradient, topCenter, midCenter, 0);
CGGradientRelease(glossGradient);
CGColorSpaceRelease(rgbColorspace);
}

Many documentations

resource

Simple XML Parser based on NSXMLParser +converter

Vladimir Boychentsov — Wed, 21 Apr 2010 11:45:16 +0000

Simple XML Parser based on NSXMLParser +converter to XML file

How To Setup:
insert next code to file “name of you project”_Prefix.pch

#import "XMLNode.h"
#import "XMLParser.h"
#import "XMLConvert.h"

Create and launching XMLParser.
You will get parsed data ( with XMLNode data type ) in callbackParser: method

NSURL *URLToFile = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"source" ofType:@"xml"]];
XMLParser *parser = [[XMLParser alloc] init];
[parser setDelegate:self withAction:@selector(callbackParser:)];
[parser parseXMLFile:URLToFile];
[parser release];

Converting results of parsing to XML file:

NSString *content = [XMLConvert convertXMLNode:root];

And additional define methods for working with XMLNode’s:
XMLaddAttribute(node, object, key), XMLgetAttribute(node, key), XMLsetParent(node, parent), XMLaddChild(parent, child), XMLgetChild(parent, child), XMLremoveChild(parent, child), XMLgetChildWithAttribute(parent, childname, object, key)

Source
Good luck!

Streatch image with stretchableImageWithLeftCapWidth: topCapHeight:

Vladimir Boychentsov — Wed, 10 Mar 2010 14:43:38 +0000

Sample

+ (UIImage*)greenBubble
{
if (sGreenBubble == nil) {
UIImage *i = [UIImage imageNamed:@"Balloon_1.png"];
sGreenBubble = [[i stretchableImageWithLeftCapWidth:15 topCapHeight:13] retain];
}
return sGreenBubble;
}
+ (UIImage*)grayBubble
{
if (sGrayBubble == nil) {
UIImage *i = [UIImage imageNamed:@"Balloon_2.png"];
sGrayBubble = [[i stretchableImageWithLeftCapWidth:21 topCapHeight:13] retain];
}
return sGrayBubble;
}

Results:

or

испоьзовал 2 картинки

Universal web services suite for iPhone/iPad and Android apps

Vladimir Boychentsov — Thu, 25 Feb 2010 12:08:13 +0000

Hi there! We are a group of iPhone / Android developers who have developed a suite of web services to assist us and other developers in building great apps.

After numerous projects we have become tired of having to set up the server scripts to do all the same things for different clients. Most of the server functionality

is typical: 1) storing location data for Google Maps; 2) storing users’ high scores / ranks; 3) sending Push Notifications; 4) storing files / XML; etc.

We couldn’t use the existent solutions because in some cases they didn’t provide the required functionality and in most cases they require your users to be exposed to some social network of theirs, while our clients just want a simple functionality without users knowing of any services behind that.

So we have launched what we call Mob1serv, a universal server solution for the typical needs of iPhone / Android apps. It consists of modules which deal with most common tasks:

* High Scores – a powerful online high scores table
* PushNote – a module allowing to send immediate or delayed Push Notifications (you can build instant messengers or alarm clocks, anything with this)
* GeoPos – stores locations of Google Map objects, their statuses and ‘last seen online’ time
* OAuth contracter – allows you to implement transparent authentication and integration with Facebook, Twitter, Google etc
* More modules to come!

We have tried to make it as simple as possible for developers, so you just need to register at the back end and then you can add as many apps as you want and start using these services. From the client (app) side, you need to add a library to your project and put a corresponding ID there, that’s it.

The service is free, it’s a ‘freemium’ model. It has been built by developers for developers. Some developers and apps are already using it as it was open for alpha testing before, but now we are launching it open for the world so that we can see what you’re thinking of it and also get your feedback of how we can improve the existent modules or what modules to add next. Welcome to Mob1serv!

Custom UINavigationBar with image and back button

Vladimir Boychentsov — Tue, 09 Feb 2010 19:10:16 +0000

Many people could not find this solution! It’s really very simple solution and it does not contain any private methods and functions. It’s based on the drawRect method and the simple manipulation with the title. If the title is specified, then the text of title displays, but if not, then displays the image.

@implementation UINavigationBar (UINavigationBarCustomDraw)
- (void) drawRect:(CGRect)rect {
[self setTintColor:[UIColor colorWithRed:0.5f
green: 0.5f
blue:0
alpha:1]];
if ([self.topItem.title length] > 0 && ![self.topItem.title isEqualToString:@"Back to ..."]) {
[[UIImage imageNamed:@"Header_1px.png"] drawInRect:rect];
CGRect frame = CGRectMake(0, 0, 320, 44);
UILabel *label = [[[UILabel alloc] initWithFrame:frame] autorelease];
[label setBackgroundColor:[UIColor clearColor]];
label.font = [UIFont boldSystemFontOfSize: 20.0];
label.shadowColor = [UIColor colorWithWhite:0.0 alpha:1];
label.textAlignment = UITextAlignmentCenter;
label.textColor = [UIColor whiteColor];
label.text = self.topItem.title;
self.topItem.titleView = label;
} else {
[[UIImage imageNamed:@"Header.png"] drawInRect:rect];
self.topItem.titleView = [[[UIView alloc] init] autorelease];
}
}
@end

source