objective-c – Imthiaz Blog

RSSReader Version 2.0 with UITabBarController

July 4, 2011
Imthiaz
Programming

Couple of months back I released an open source RSS Reader app for iPhone on GitHub. Most of the people who downloaded the source requested for an updated version using UITabBarController.

Today I am releasing version 2.0 with the following changes

Updated the views to use UITabBarController
Loads rss subscription from plist file
More fun to learn 😉

Download RSSReader Version 2.0 with complete source for iPhone. To see complete list of changes visit RSSReader on Github

Note: This source code does not have any license nor warranty. Please feel free to use this in any of your projects and don’t have to email me.

Enjoy, Happy Coding 😉

UIScreen Notifications for connecting external display in iOS

April 29, 2011
Imthiaz
Programming

UIScreen class has three main notifications which gets triggered when a new screen (external display) is attached to the device.

UIScreenDidConnectNotification

This notification is posted when a new screen is connected to the device. The object of the notification is the UIScreen object representing the new screen. There is no userInfo dictionary. Connection notifications are not sent for screens that are already present when the application is launched. The application can instead use the screens method to get the current set of screens at launch time.

UIScreenDidDisconnectNotification

This notification is posted when a screen is disconnected from the device. The object of the notification is the UIScreen object that represented the now disconnected screen. There is no userInfo dictionary.

UIScreenModeDidChangeNotification

This notification is posted when the current mode of a screen changes. The object of the notification is the UIScreen object whose currentMode property changed. There is no userInfo dictionary. Clients can use this notification to detect changes in the screen resolution.

Simple code to listen to the notification

- (void)awakeFromNib{
    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
    [center addObserver:self selector:@selector(screenDidConnect:) name:UIScreenDidConnectNotification object:nil]; 
    [center addObserver:self selector:@selector(screenDidDisconnect:) name:UIScreenDidDisconnectNotification object:nil]; 
    [center addObserver:self selector:@selector(screenModeDidChange:) name:UIScreenModeDidChangeNotification object:nil]; 
}

- (void) screenDidConnect:(NSNotification *)aNotification{
    NSLog(@"A new screen got connected: %@", [aNotification object]);
}

- (void) screenDidDisconnect:(NSNotification *)aNotification{
    NSLog(@"A screen got disconnected: %@", [aNotification object]);
}

- (void) screenModeDidChange:(NSNotification *)aNotification{
    UIScreen *someScreen = [aNotification object];
    NSLog(@"The screen mode for a screen did change: %@", [someScreen currentMode]);

}

- (void)dealloc{
    NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
    [center removeObserver:self name:UIScreenDidConnectNotification object:nil];
    [center removeObserver:self name:UIScreenDidDisconnectNotification object:nil];
    [center removeObserver:self name:UIScreenModeDidChangeNotification object:nil];
	//....
	[super dealloc];
}

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- (void)awakeFromNib{

NSNotificationCenter *center = [NSNotificationCenter defaultCenter];

[center addObserver:self selector:@selector(screenDidConnect:) name:UIScreenDidConnectNotification object:nil];

[center addObserver:self selector:@selector(screenDidDisconnect:) name:UIScreenDidDisconnectNotification object:nil];

[center addObserver:self selector:@selector(screenModeDidChange:) name:UIScreenModeDidChangeNotification object:nil];

}

- (void) screenDidConnect:(NSNotification *)aNotification{

NSLog(@"A new screen got connected: %@", [aNotification object]);

}

- (void) screenDidDisconnect:(NSNotification *)aNotification{

NSLog(@"A screen got disconnected: %@", [aNotification object]);

}

- (void) screenModeDidChange:(NSNotification *)aNotification{

UIScreen *someScreen = [aNotification object];

NSLog(@"The screen mode for a screen did change: %@", [someScreen currentMode]);

}

- (void)dealloc{

NSNotificationCenter *center = [NSNotificationCenter defaultCenter];

[center removeObserver:self name:UIScreenDidConnectNotification object:nil];

[center removeObserver:self name:UIScreenDidDisconnectNotification object:nil];

[center removeObserver:self name:UIScreenModeDidChangeNotification object:nil];

//....

[super dealloc];

}

If anyone is interested in screen mirroring in iPhone / iPad check this UIScreen Additions.

iPhone RSS Reader with source code

April 3, 2011
Imthiaz
Programming

Last week I had prepared simple RSSReader application for demoing at Arabnet Shift Digital Summit. Since there was not much time to really explain I had to cut short my presentation with a very basic application demo. I promised to few programmers at Arabnet that I will release the source code for this application on my blog.

Unlike my previous version of RSSReader this version is much cleaner and simple to understand. Removed lots of unwanted methods and made it as simple as possible to understand. When I released the last RSSReader code I received lots of emails asking for updates and some people wanted to fix and update few things to it. To enable all this I am releasing this source code at gitHub.

https://github.com/hmimthiaz/RSSReader

This source code does not have any license nor warranty. Please feel free to use this in any of your projects and don’t have to email me.

Enjoy, Happy Coding 😉

iPhone SDK base64 encode / decode

August 16, 2010
Imthiaz
Programming

I found this useful class for base64 encoding / decoding. It is written by Kiichi Takeuchi

Base64.h

@interface Base64 : NSObject {
}

+ (void) initialize;
+ (NSString*) encode:(const uint8_t*) input length:(NSInteger) length;
+ (NSString*) encode:(NSData*) rawBytes;
+ (NSData*) decode:(const char*) string length:(NSInteger) inputLength;
+ (NSData*) decode:(NSString*) string;

@end

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@interface Base64 : NSObject {

}

+ (void) initialize;

+ (NSString*) encode:(const uint8_t*) input length:(NSInteger) length;

+ (NSString*) encode:(NSData*) rawBytes;

+ (NSData*) decode:(const char*) string length:(NSInteger) inputLength;

+ (NSData*) decode:(NSString*) string;

@end

Sample Usage

[Base64 initialize];
NSData * data = [Base64 decode:@"SGVsbG8gV29ybGQ="];
NSString * actualString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"%@",actualString);
[actualString release];

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[Base64 initialize];

NSData * data = [Base64 decode:@"SGVsbG8gV29ybGQ="];

NSString * actualString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

NSLog(@"%@",actualString);

[actualString release];

Download base64 encode / decode class

iPhone SDK generate MD5 Hash of a string

August 16, 2010
Imthiaz
Programming

This function will help you generate MD5 hash of a given string

Class.h

+ (NSString *)getMD5FromString:(NSString *)source;

1	+ (NSString )getMD5FromString:(NSString )source;

Class.m

+ (NSString *)getMD5FromString:(NSString *)source{
	const char *src = [source UTF8String];
	unsigned char result[CC_MD5_DIGEST_LENGTH];
	CC_MD5(src, strlen(src), result);
    NSString *ret = [[[NSString alloc] initWithFormat:@"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X", 
					  result[0], result[1], result[2], result[3],
					  result[4], result[5], result[6], result[7],
					  result[8], result[9], result[10], result[11],
					  result[12], result[13], result[14], result[15]
					  ] autorelease];
    return [ret lowercaseString];
}

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+ (NSString *)getMD5FromString:(NSString *)source{

const char *src = [source UTF8String];

unsigned char result[CC_MD5_DIGEST_LENGTH];

CC_MD5(src, strlen(src), result);

NSString *ret = [[[NSString alloc] initWithFormat:@"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",

result[0], result[1], result[2], result[3],

result[4], result[5], result[6], result[7],

result[8], result[9], result[10], result[11],

result[12], result[13], result[14], result[15]

] autorelease];

return [ret lowercaseString];

}