i want to ask what is right way to use this UICollectionViewDiffableDataSource... I need to use this for live updates from api. I get add,remove,change then i have to make sections with items from this data and order the sections and items in sections by some rules...I want to ask if i should do the some logic to update the snapshot every time i get updates from api or i can just create new snapshot and apply it to the datasource. What it will do if i apply new snapshot? Is there some mechanism that compares the snapshot? Or it reloads whole collectionView? Thanks.
You should create a new snapshot after every API update and apply it to the diffable data source.
The diffable data source will compare the hash value of each item identifier in the snapshot to see if the data has changed, and will update the collection view accordingly. If the data remains the same, it will have the same hash value, so no updates will be made to the collectionview.
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I am deleting row from a sheet, On a sheet I have daily job which needs to recognize the deleted records, I need a way to recognize them using smartsheet api or sdk..
Thanks in advance..
I don't believe this scenario (identifying deleted rows) is explicitly supported by the API at this time. Seems like you could still use the API to achieve your goal though, with a bit more work (code) on your part.
Your code would have to get the sheet data (i.e., all sheet rows) at a regular interval and save that data somewhere -- then each time job runs, get the sheet data again and compare that data to the data you saved the previous time the job ran (to identify any rows that had been deleted).
Edit 9/26: Added Webhooks info
Note that with the approach I've described above, any rows that had been added AND deleted during the interval between job runs would not be detected. If it's important to identify each and every time a row is deleted, a better (and much more efficient) approach would be to use Webhooks. By using webhooks, your application subscribes to notifications for a specified sheet, and then would receive a callback (HTTP POST) from Smartsheet any time the sheet changes. Your application would need to inspect the information in each callback it receives to identify 'deleted row' events (eventType = deleted and objectType = row).
A simple way to do this is to add a column with a checkmark named "delete" or something similar, then with automation you can move the row to another sheet when the flag is detected, the row will be removed from the original sheet, but you will have a record of the deleted row in a different sheet that you can read or do what ever you need to do, this will also prevent deletions by mistake and you can even restore the row back if you need to. I don't think you need much code to implement this solution.
I have a reorderable list where i read the further information of each row on tap from a json file. Each row displays the corresponding json files name. I read these from a local folder in users device. The list shown here enables the user to reorder the items. The problem is I want to ensure persistent reodering by which I mean my app should remember the ordering user made next time the app is launched. I cannot think of anyway to go with this. Do I store a local json file keeping all the file names and the corresponding row index? What would be a best practice for this. This list is though to have row amount of 50 to 200 so I need a scalable solution.
I'm trying to build a caching system for a feed reading application. The idea is each time a new feed is successfully pulled, remove all stored entities in Core Data, and store the first twenty items of the feed (this is used as an offline cache).
The issue I'm running into is my managed object context may have hundreds of items in it when a pull to refresh is performed. I'd like to keep those items in the context while removing any stored items from Core Data and then store the twenty items returned from the refresh call.
For what it's worth, I'm using Magical Record. I've tried looking around for this solution, but either I'm using the wrong keywords or the information is hard to find.
I'm not sure what code to show exactly, but here's the handling of the feed call:
for (id dict in feedArray){
WFeedItem *item = [WFeedItem feedItemWithAttributes:[dict dictionaryByReplacingNullsWithBlanks] inManagedObjectContext:[NSManagedObjectContext defaultContext]];
[parsedArray addObject:item];
}
This gets passed back from the subclassed HTTPClient it's defined in to a view controller that has called it. Bear in mind, this all works fine, it's all a matter of deleting stored items while retaining everything I've gathered during this session in the context.
Just use a different context for importing and storing the new records. Your original object context can remain as it is.
I am implementing tableView which loads data from server. I got two scenario:
Get complete data from the server and store in the array say 500 items. Now whenever I need those data I will call my array and fetch data accordingly. In this case, loading huge data from server at first time will take place.
Get required data say 15 from the server and store in the Mutable array. And, if User has scroll down ,get data from the server again and add those in mutable array and display those in the table accordingly. In this case, whenever user will scroll up and down, we have to call server like Lazy Loading.
So, which would be appropriate way to load table from server.Any Feedback will be appreciated.
I think you should be use Lazy Loading. Pull To Refresh.... tableview is available for that. every refresh get 15 records and add into your array. i think this is the best way. because if you load 500 items at a time and any user required only 5th item, so other record are not useful..so i suggested you to use 2nd way.
I think for better solution you can have a bottom cell named "Load more items", click on that cell will load next set of items, it will help both user and programmer for avoiding unwanted items.
What I'm trying to accomplish is the following: I need to limit the amount of core data entries to 50. So if the user enters their 50th entry then the app would delete the oldest entry and add the new entry to the top of the stack. So basically, if the user never deletes entries and if there are 50 entries in core data then, when the user tries to add a new entry, the app would delete the oldest entry and add the user's new entry. Basically, I'm trying to have a history sort of thing but I don't want the user to be able to go past 50 entries however I want them to be able to add new entries when their at the 50 limit by just dropping the oldest one and adding the newest one. What would be the easiest way to do this? I'm new to core data and having a hard time understanding a lot of it. Here's the code / example app that I'm working with. LINK TO EXAMPLE APP THAT I'M USING Thanks for the help.
Let's say you have an entity called History. The easiest solution would be to add a creationDate attribute to your entities. Then use that to manage your History objects.
You will need three fetches:
The first one will fetch as faults all the existing History objects and then count them. If the count is <50, then just add the new History object and your done.
If the count>=50, then do a fetch for specific value and use the #max or #min (I forget which for dates) collections operator to find the oldest creationDate. (As luck would have it the example at the link it pretty much exactly what you need.)
Perform a fetch for the object with the creationDate returned by (2) and delete it.
Then add the new history object.
OK, that's fine. CoreData is not going to do this for you, but you can do it yourself.
You can retrieve objects from you context using an NSFetchRequest, and you can delete them using -[NSManagedObjectContext deleteObject:]. You can sort them using NSSortDescriptor objects.