NSPredicates, scopes and SearchDisplayController
Building a search with some custom objects and three scopes: All, Active, and Former. Got it working with the below code:
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString *)scope {
[[self filteredArtists] removeAllObjects];
for (HPArtist *artist in [self artistList]) {
if ([scope isEqualToString:@"All"] || [[artist status] isEqualToString:scope]) {
NSComparisonResult result = [[artist di开发者_Go百科splayName] compare:searchText options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch) range:NSMakeRange(0, [searchText length])];
if (result == NSOrderedSame) {
[[self filteredArtists] addObject:artist];
}
}
}
}
This works fine and takes scope
into account. Since I wanted to search four fields at at time, this question helped me come up with the below code:
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString *)scope {
[[self filteredArtists] removeAllObjects];
NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:@"familyName CONTAINS[cd] %@ OR familyKanji CONTAINS[cd] %@ OR givenName CONTAINS[cd] %@ OR givenKanji CONTAINS[cd] %@", searchText, searchText, searchText, searchText];
[[self filteredArtists] addObjectsFromArray:[[self artistList] filteredArrayUsingPredicate:resultPredicate]];
}
However it no longer takes scope into account.
I have been playing around with if
statements, adding AND scope == 'Active'
, etc. to the end of the statement and using NSCompoundPredicates
to no avail. Whenever I activate a scope, I'm not getting any matches for it.
Just a note that I've seen approaches like this one that take scope into account, however they only search inside one property.
Here's about how I would do it:
NSPredicate * template = [NSPredicate predicateWithFormat:@"familyName CONTAINS[cd] $SEARCH "
@"OR familyKanji CONTAINS[cd] $SEARCH "
@"OR givenName CONTAINS[cd] $SEARCH "
@"OR givenKanji CONTAINS[cd] $SEARCH"];
- (void)filterContentForSearchText:(NSString *)search scope:(NSString *)scope {
NSPredicate * actual = [template predicateWithSubstitutionVariables:[NSDictionary dictionaryWithObject:search forKey:@"SEARCH"]];
if ([scope isEqual:@"All"] == NO) {
NSPredicate * scopePredicate = [NSPredicate predicateWithFormat:@"scope == %@", scope];
actual = [NSCompoundPredicate andPredicateWithSubpredicates:[NSArray arrayWithObjects:actual, scopePredicate, nil]];
}
[[self filteredArtists] setArray:[[self artistList] filteredArrayUsingPredicate:actual]];
}
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