Test URL connection

ConnectionTestAppDelegate.h

//
//  ConnectionTestAppDelegate.h
//  ConnectionTest
//
//  Created by Hank Wang on 2011/2/9.
//

#import <UIKit/UIKit.h>

@interface ConnectionTestAppDelegate : NSObject <UIApplicationDelegate, UIAlertViewDelegate> {
    UIWindow *window;
    NSURLConnection *urlConnection;
}

- (void)startConnection;

@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) NSURLConnection *urlConnection;

@end

ConnectionTestAppDelegate.m

//
//  ConnectionTestAppDelegate.m
//  ConnectionTest
//
//  Created by Hank Wang on 2011/2/9.
//

#import "ConnectionTestAppDelegate.h"

@implementation ConnectionTestAppDelegate

@synthesize window, urlConnection;


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    [self.window makeKeyAndVisible];
    [self startConnection];
    return YES;
}

- (void)startConnection {
    // Connection Request
    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.google.com"]];

    self.urlConnection = [[[NSURLConnection alloc] initWithRequest:request delegate:self] autorelease];

    [UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
}

// -------------
//	handleError:error
// -------------
- (void)handleError:(NSError *)error
{
    NSString *errorMessage = [error localizedDescription];
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Connect Test"
                                                        message:errorMessage
                                                       delegate:self
                                              cancelButtonTitle:@"Cancel"
                                              otherButtonTitles:@"Retry", nil];
    [alertView show];
    [alertView release];
}


// -------------
//	connection:didReceiveResponse:response
// -------------
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    NSLog(@"%@", @"didReceiveResponse");
}


// -------------
//	connection:didReceiveData:data
// -------------
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    NSLog(@"%@", @"didReceiveData");
}


// -------------
//	connection:didFailWithError:error
// -------------
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    NSLog(@"%@", @"didFailWithError");
	
    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
    
    if ([error code] == kCFURLErrorNotConnectedToInternet) {
        // if we can identify the error, we can present a more precise message to the user.
        NSDictionary *userInfo = [NSDictionary dictionaryWithObject:@"Connection Failed"
                                                             forKey:NSLocalizedDescriptionKey];
		
        NSError *noConnectionError = [NSError errorWithDomain:NSCocoaErrorDomain
                                                         code:kCFURLErrorNotConnectedToInternet
                                                     userInfo:userInfo];
        [self handleError:noConnectionError];

    } else {

        // otherwise handle the error generically
        [self handleError:error];

    }
    
    self.urlConnection = nil;   // release connection
}


// -------------
//	connectionDidFinishLoading:connection
// -------------
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    self.urlConnection = nil;   // release connection
    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
	
	// show successful
	UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Connect Test"
                                                            message:@"Connection Successful"
                                                           delegate:nil
                                                  cancelButtonTitle:@"OK"
                                                  otherButtonTitles:nil];
    [alertView show];
    [alertView release];
	
    NSLog(@"%@", @"connectionDidFinishLoading");
}


// -----
// alertView:alertView clickedButtonAtIndex:buttonIndex
// -----
- (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
	switch (buttonIndex) {
		case 0:
			NSLog(@"Button Cancel Pressed");
			break;
		case 1:
			NSLog(@"Button Retry Pressed");
			[self startConnection];
			break;
			
		default:
			break;
	}
}


- (void)dealloc {
	[self.urlConnection release];
    [window release];
    [super dealloc];
}

@end