UISearchBar clearButton

When the searchBar:textDidChange: method of the UISearchBarDelegate gets called because of the user tapping the 'clear' button, the searchBar hasn't become the first responder yet, so we can take advantage of that in order to detect when the user in fact intended to clear the search and not bring focus to the searchBar and/or do something else.

To keep track of that, we need to declare a BOOL ivar in our viewController that is also the searchBar delegate (let's call it shouldBeginEditing) and set it with an initial value of YES (supposing our viewController class is called SearchViewController):

@interface SearchViewController : UIViewController <UISearchBarDelegate> {
    // all of our ivar declarations go here...
    BOOL shouldBeginEditing;
    ....
}

...
@end

@implementation SearchViewController
...
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if ((self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil])) {
        ...
        shouldBeginEditing = YES;
    }
}
...
@end

Later on, in the UISearchBarDelegate, we implement the searchBar:textDidChange: andsearchBarShouldBeginEditing: methods:

- (void)searchBar:(UISearchBar *)bar textDidChange:(NSString *)searchText {
    NSLog(@"searchBar:textDidChange: isFirstResponder: %i", [self.searchBar isFirstResponder]);
    if(![searchBar isFirstResponder]) {
        // user tapped the 'clear' button
        shouldBeginEditing = NO;
        // do whatever I want to happen when the user clears the search...
    }
}

- (BOOL)searchBarShouldBeginEditing:(UISearchBar *)bar {
    // reset the shouldBeginEditing BOOL ivar to YES, but first take its value and use it to return it from the method call
    BOOL boolToReturn = shouldBeginEditing;
    shouldBeginEditing = YES;
    return boolToReturn;
}

http://stackoverflow.com/questions/1092246/uisearchbar-clearbutton-forces-the-keyboard-to-appear/3852509#3852509