I have 3 core data entities.
MenuItems, Items, ItemLangs.
All entities has iItemId attribute. The user need to search using sItemName which can be found in the ItemLangs.
The UITableView contains array of MenuItems.
I have tried filteredArrayUsingPredicate but my predicate is not right. Do I need to loop through the array of MenuItems first before I can filter the array?
Here is my predicate:
NSPredicate *resultPredicate = [NSPredicate
predicateWithFormat:#"sItemName LIKE %#", searchText];
May I know how can I use this to filter the array of MenuItems that I have?
Thank you!
What you need is a predicate like this:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"sItemName CONTAINS[cd] %#", searchText];
[cd] stands for case insensitiveness.
Alternately, if you like "LIKE", refer to this answer.
UPDATE:
You should also look at the data item you want to fetch - sItemName in your case. Through debugger, inspect what object does your data source array return? I am referring to the array you want to apply the above predicate to. Maybe there is some keypath hierarchy involved in getting through towards sItemName, in which case you need to use dot notation, such as Items.ItemLangs.sItemName.
Refer following links, it may help you:
1) How to implement SearchBar and search display controller in tableview in xib
2) first attempt at synamic filtering a search array
3) http://www.appcoda.com/search-bar-tutorial-ios7/
4) http://www.raywenderlich.com/16873/how-to-add-search-into-a-table-view
Related
For a search bar of contacts I am using an NSPredicate to filter results. I have used the exact same code on other entities without an issue. However, when I use it on this one entity, it returns the error:
Can't use in/contains operator with collection FIRST (not a collection)
Here is the code.
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope
{
NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:#"first contains[c] %#", searchText];
searchResults = [getContacts filteredArrayUsingPredicate:resultPredicate];
}
Not all the records have first which refers to first name. Could it be that null values for first are causing the error? If so, how would I allow for null values?
Alternatively, what else could be causing this error?
It looks like FIRST is being interpreted as an aggregate operation. Try changing it to firstName. This will make it clearer for coredata and also your future self (some time in the future you may add an address with firstLine for street address which could be confusing)
Im trying to implement something that I'm sure have been implemented a million times before, a search in the core data database, displayed in a table using a fetchRequestController and the searchController.
My problem is writing the NSPredicate for the NSFetchRequest. According to the NSPredicate guide by Apple, not everything you can do in Sqlite is possible with core data.
I have been trying to find a solution for some time, but maybe one of you can use his experience to help me.
CoreData DB description:
Shops has a MANY TO MANY relationship with DiscountProgam.
My use case is as follows: I need to filter out Shops who's name/address/zip/city contains the search string. that's the easy part.
The hard part is creating the section of the database I want to filter from, because I have an array of "active" discountPrograms UID's, and I only want shops that have one of the active discount programs in their "discountPrograms" set. So in pseudo code that would be:
FROM Shops who have at least one discountProgram who's uid IN activeDiscountProgramsArray WHERE name/address/zip/city CONTAINS searchString
Is this possible? am I over reaching the limits of predicates?
If so, how could I do it differently?
Yes, NSPredicate can analyse both the direct attributes of the target entity of a fetch and the attributes of its relationships. Try:
NSArray *validUIDs = ...;
NSString *searchTerm = ...;
[NSPredicate predicateWithFormat:#"(name CONTAINS[cd] %# OR zip CONTAINS[cd] %#) AND (SUBQUERY(discountProgram, $d, $d.UID IN %#).#count > 0)", searchTerm, searchTerm, validUIDs];
I am trying to write a query that gets a row when the id is equal to 1 (at the moment).
NSPredicate *predicate = [NSPredicate predicateWithFormat:[apt[#"id"] isEqualToNumber:1]];
So where id (from another database) is equal to 1. Now this is complaining all sorts of things but its saying it needs to be a BOOL. Is NSPredicate needing a BOOL?
Not sure I understand, or is there another way I can query? Can I use T-SQL in Mobile Services SDK Azure for iOS?
The predicate with format expects a string, you are sending in a bool. [apt[#"id"] isEqualToNumber:1] returns a bool.
Use the predicate in this manner (I have little experience with formatting predicates, so this will likely not actually work for you to copy and paste in).
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"id == 1"];
This will work if your objects in the array you are filtering have a property called id.
Something I understand a littler better is predicates with blocks. This could work for you too (I'm not entirely sure of your data structure, so you are gong to have to modify to suit your needs.
NSPredicate *predicate = [NSPredicate predicateWithBlock:^BOOL(id object, NSDictionary *bindings) {
return [object[#"id"] isEqualToNumber:1]; // Return YES for each object you want in filteredArray.
}]
I'm working on an app where I have two entities, Post <-->> StreamType. When I create posts I assign StreamType:s like this:
// streamType == one of my default streamTypes
[post addStreamTypesObject:streamType];
My predicate for finding posts that have a certain StreamType looks like this:
predicate = [NSPredicate predicateWithFormat:#"ANY streamTypes.type = %#", [NSNumber numberWithInt:self.pageType]];
I'm not sure why this happens. Any ideas?
Edit
What I basically want is to fetch all Posts that have the right StreamType. Seemed after all that my fetchrequest only returns 1 item from the database. So probably nothing wrong with my tableview.
Edit 3
The problem was with my relationship, should be many-to-many, not one to many. Therefore it only returned one Post item.
First: test if the other code is ok. Simply, remove the predicate (comment the setPredicate line). You should see ALL objects in your tableview.
Right?
Second: check if self.pageType is set correctly. I don't see in your code how you set self.pageType
Test your predicate, add an NSLog like this and check if the result is ok:
NSLog(#"ANY streamTypes.type = %d", self.pageType);
Third:
As far as I understand, you have this situation:
One Post has only one stream type
One stream type has multiple posts.
The ANY keyword is used in situations where you want, for example, obtain all stream types where a particular condition is satisfied at least one time. for example (assuming you have a "content" instance variable on your post, containing the text of the post)
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"ANY post.content CONTAINS[cd] %#", #"aWord"];
In this case, you will obtain all stream types in which there are posts containing "aWord" particular word in the text.
Your case is simpler. I think that you should simply use:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"streamTypes.type = %d", self.pageType];
Try and let me know
I was just having the same issue using Core Data with Swift and just wanted to add this answer in incase anybody else is having a similar issue.
This was my NSPredicate code:
let predicate = NSPredicate(format: "routine == %#", self.selectedRoutine)
Routine holds multiple exercise objects which I was trying to return. An exercise can only have one routine but a routine can have many exercises.
Turns out I'd forgotten to select 'To Many' as the relationship type for the exercises relationship in my routine entity using the Data Model inspector. It was set as 'To One'.
I am trying to write a predicate similar to
[NSPredicate predicateWithFormat:#"ANY manyNames in %#", allNames];
but instead of 'in' I need 'like'
[NSPredicate predicateWithFormat:#"ANY manyNames like %#", allNames];
This causes an error.
So I want to get results with some objects of manyNames, which are similiar to at least one of allNames.
I solved my problem by joining the strings and making one string of them, then looking for that.