isEqualToString: gives out of bound exception

Question

Today I received a random crash on the isEqualToString method used with text property of UISearchBar. The crash was reported on Crashlytics.

Following is the code snippet.

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
    if( [searchBar.text isEqualToString:@" "] )
    {
        [searchBar setText:@""];
    }
    if ( searchBar.text.length >= 2 )
    {
        [self performSelectorInBackground:@selector(searchForKeyword:) withObject:searchBar.text];
    }
}

-(void)searchForKeyword:(NSString *)keyword
{
    if ([keyword isEqualToString:searchBar.text])
    {
        //Search for keyword
    }
}

The crash says

Fatal Exception: `NSRangeException`
*** -[NSBigMutableString _newBigSubstringWithRange:wantsMutable:zone:]: Range {0, 4} out of bounds; string length 3

I have tried debugging line of code that is causing the crash but with no success. It is just randomly crashing. Thanks in advance

What is `keyword` can you put the whole code before the `if condition`? — iphonic, Jul 04 '16 at 07:33
Use `performSelector` instead of `performSelectorInBackground` and check. — iphonic, Jul 04 '16 at 08:53
@Proton: No. It's a random crash. It was reported on Crashlytics only once. — Anoop Nyati, Jul 04 '16 at 09:09
@iphonic: Ok, will give it try. But do you think it would resolve the issue? Crash log says something "out of bound substringWithRange" error — Anoop Nyati, Jul 04 '16 at 09:10

score 1 · Accepted Answer · answered Jul 04 '16 at 09:35

The error is caused by that:You set the search bar text in

- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText

You should use the method below instead of what you use.

- (BOOL)searchBar:(UISearchBar *)searchBar shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text NS_AVAILABLE_IOS(3_0); // called before text changes

isEqualToString: gives out of bound exception

1 Answers1