How to show alert for iOS?

This is how you can show an alert box in iPhone or iPad app.


In your code include the following:

UIAlertView *alert = [[UIAlertView alloc] init];
[alert setTitle:@"Confirm"];
[alert setMessage:@"Buy This?"];
[alert setDelegate:self];
[alert addButtonWithTitle:@"Yes"];
[alert addButtonWithTitle:@"No"];
[alert show];
[alert release];

Then implement this in the delegate, in this case, the controller which calls UIAlertView.

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 0)
{
// Yes, do something
NSLog(@"Yes!");
}
else if (buttonIndex == 1)
{
// No
NSLog(@"No!");
}
}

how to list files in iOS

This is how you can list files in your iPhone apps.

NSFileManager *manager = [NSFileManager defaultManager];
NSArray *fileList = [manager directoryContentsAtPath:documentsDirectory];
for (NSString *s in fileList){
NSLog(s);
}

How to test if file exist in iPhone iOS

BOOL fileExists = [[NSFileManager defaultManager] fileExistsAtPath:somePath];

How to get Application Name with code

Below is how you can get the name of your application with code.

[[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleName"]

How to enable SQL debugging for Core Data in XCode

Right click on the project executable and click “Get Info.” Navigate to the Arguments tab and add the following argument: “-com.apple.CoreData.SQLDebug 1″.

When the project is running, you should see the sql used in the console.

Thanks to http://www.raywenderlich.com/934/core-data-tutorial-getting-started