What I am looking to do is have 2 sections in my tableview which I can do by specifying 2. From there I am stuck. I am performing 2 queries from Parse to gather the details I need. 1 query gather extremely urgent data and the second is data about less important events. Each query has its own array so I am thinking it should be pretty easy to accomplish.
How do I set the first section to the urgent array (self.urgent) and the second to the less important events array (self.event)? I know how to configure cells for a single section with an array but have never had to configure 2 section with different results.
Thank you in advance.
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I've been working on building a data analysis sheet, which is quite verbose at the moment and a bit more complicated than it should be as I've been trying to figure this out. Please note, I work doing student data in a school.
Basically, I have two sets of input data:
Data imported from a CSV file that includes test data and codes for Common Core Standards and the questions tied to those standards as a whole class summary
Data imported from a CSV file that includes individual scores by question
I am looking to construct 2 views:
A view that collates and displays data of individual standards per student that includes a dropdown to change the standard allowing a teacher to see class performance by standard in a broad view. The drop-down is populated dynamically from the input data (so staff could eventually dump data and go directly to reports)
A view that collates and displays data of individual students broken down by performance on each standard allowing a teachers to see the broader spectrum for each student. The student drop-down is populated from Source list 2.
I have been able to build the first view, but am struggling with the second. I've been able to separate the question codes and develop strings of cell references to the scoring data, including a dynamic reference to the row the selected student's score data appears on in the second source set from above.
I tried to pass through an indirect() formula into a sum() so as to process for a mean evaluation, and have encountered errors. I think SUM() doesn't process comma-separated cell reference lists from Indirect() [or in general] or there is something that I am missing to help parse it. Here is the formula I have tried:
=Sum(vlookup(D7,CCCodeManip!$A:$C,3,false))
CCCodeManip!C:C includes the created text (based on the dynamic standards and question codes, etc), here's an example of what would be found there:
'M-ADI'!M17, 'M-ADI'!N17, 'M-ADI'!O17, 'M-ADI'!P17, 'M-ADI'!Q17, 'M-ADI'!R17, 'M-ADI'!J17
I need these to be dynamic so that teachers can input different sets of standards, question, and student data and the sheet automatically collates and reports it in uniform ways (with an upward bound of 20 standards as I currently have it built)
Here is a link to the sheet I built, with names and ID anonymized. There's a CRAP TON of sub-tabs, and that's really just being able to split apart and re-combine data neatly without things error-ing out due to data overlapping, aside from a few different attempts and different approaches to parse the cell reference strings.
The first two tabs are the current status of the data views. I plan to hide a bunch of the functional stuff that is there to help pull data accurately.
The 3rd and 4th tab are the source data sets. 5th is a modified version of source data that allows me to reference things better, and I've tried to arrange the sheets most relevant towards the front of the set.
https://docs.google.com/spreadsheets/d/1fR_2n60lenxkvjZSzp2VDGyTUO6l-3wzwaV4P-IQ_5Y/edit?usp=sharing
Some have a different approach? I am aware that I might be as far as I cn go with this and perhaps should consider scripts - my coding experience is a bit out of date and my strength is more with the formulas, but I can dig into things with some direction, if anyone can help.
Ok so I noticed something.
It seems the failure is in the indirect reference:
=indirect(CCCodeManip!C3)
The string I am trying to parse via indirect is going to be generated into something like this, dynamic from reference to other data:
'M-ADI'!M17, 'M-ADI'!N17, 'M-ADI'!O17, 'M-ADI'!P17, 'M-ADI'!Q17, 'M-ADI'!R17, 'M-ADI'!J17
The indirect returns the error that the above string is not a cell reference with the #REF code.
Can someone give me a clue as to what is causing this? I am going to dig into the docs on Indirect() from google and will post anything that I find.
Perhaps it is that indirect() can't handle lists, but only specific references and arrays, which may require me a to build a sheet to do the SUM formula on for each question set (?)
So I think I figured it out, but i Ended up parsing the data differently, basically doing the sum based on individual cell references and a separate sum formula, bypassing the need to do it all at once, it jsut makes my sheets a lot dirtier! I am eventually going to see if code could do it better if I need to, but this is closed for now.
Basically, I did individual cell references to recall scores in a row, then used a separate SUM formula, and created references / structures to be able to pull those sum() results. Achieves the same end, but with extra crap on the sheet.
I know how to implement pagination with UITableview but my question is we always append data of next page with existing complete data array so every next page array is increasing array size.
For example - We get 50 records in first page and we request for next page and we again get 50 records and then we will append that records in existing complete array so complete array is now having 100 records. I am requesting data with around 100 pages so my array will have 5000 records as we know holding some starting page array data is not good idea as we hardly come back for starting page after visited 100 pages .
Is there any way to optimize array size? please help me on this as i searched a lot but didn't find good answer for this.
I would be very grateful for help and sorry for my bad english.
I think you can achieve that by writing the "old" data to a local storage, and retrieve and insert back into your array.
So, imagine that you've already fetched, lets say 200 items. So when the user scrolls down, and you fetched the next page (the next 20 items), you "cut" from your array the items from 0 to 99 and write to a file. Now your array has 120 items. Then, when the user continues scrolling and again reached 220 (array.count >= 220), repeat the same logic, and so on.
Now the most interesting part. If the user scrolls back and the index of the top visible cell is <100, you read the previously written data from the file (and remove from the file) and insert into your array at 0 position.
And of course it'd be better to clear all that kind of files on the app launch.
Of course the numbers I wrote below are magic numbers and you should play with them to find the right ones that best fit your needs.
I'm using Firebase for my iOS application and I'm having trouble implement infinite scroll and filtering data together.
What I need to do is:
Display items with order/filter on multiple property (location, category, status . . .)
Implement infinite scroll when the user scrolled to bottom of the screen.
I tried to think about some solutions:
The first, I think that I'll query the data with the necessary conditions then limit the number of records by use queryLimitedToFirst(N), and increase N when need to load the next items. But because Firebase can only filter on one property at a time and it's also a waste to reload data. So, I was thinking about the second solution.
As approaches are suggested from Frank van Puffelen (Query based on multiple where clauses in firebase):
filter most on the server, do the rest on the client
Yes, exactly like that. I'll execute queryOrderedByKey, queryStartingAtValue, queryEndingAtValue to implement infinite scroll, pull down the remaining data and filter that on client. But there is one problem that is I would not have enough items to display for the user if execute filter on the client.
For example: each time run the query, I receive 10 items. After data filtering process on the client, I just left 5 (can be 0) items meet the conditions to display to the user.
I don't want this because user may think there is a problem
Can I please get some pointers on this? If I didn't structured the data properly, can I also get some tips there?
So I have a TableView contains sections that can possibly hold a different amount of cells depending on the user input for rows for detail. I trying to learn more about saving and want make a simple app that allows the user to save recipe ingredients. For example I can have 5 different sections containing 5 different types of food like -> banana: amount-2 Calories-10 Details-Slice, Apple amount-3 Calories-20 Details-Mash <-. The User would then click done and his or her recipe name will be saved and displayed on a cell in another table view. Once the user clicks on it he/she can see what he/she put and can edit it if he/she desires. I was told that Core Data would be best for this type of saving.
How could I save all the info in a organized way. I know how to save individual cells using Core Data but what is hard about this is each section can contain a unique number of cells and then this data is all saved into one data entry. It's like an array inside of an array inside of an array. I also have a feeling that I have to use dictionaries. I can't seem to structure all of this data. Can anyone help or have any tips on how I should attack this? I'm using Swift by the way.
Picture of what one section of the TableView might look like:
There's several ways you can tackle this situation. The first solution that came to mind was storing a unique array for each section that you want to display. E.g. a fruit array, vegetable array, etc. If you did this, when you fetch from Core Data you would store the items in the appropriate arrays and do something similar to the following within your numberOfRowsForSection:
switch (section) {
case 0:
return fruit.count()
case 1:
return vegetable.count()
default:
return 0
}
That switch statement will be called according to whichever section you are in at the time. If you went with a different route like a dictionary, instead of returning the count of the different array, you could return typeDict.objectForKey("fruit") instead.
I have core data entries displayed in a collectionView, sorted from 1 2 3 ... n. New batches of entries are added as the user flips through the first n. Data is built from a JSON response obtained from a web server.
Because the first entry of the fetch request is associated to cell 0 - via the datasource delegate -, it's not possible to add a new batch at the bottom of the collection view. If it's added from cell 0, old cell contents are replaced by new ones, or in short the whole page seems to be replaced by new stuff, and the data the user was looking at is offset by the number of new entry. If the batch is large, it's simply buried. Furthermore, if the update is done from cell 0, all entries are made visible, which takes time and memory.
There are several options that I considered:
1) data-redorder, meaning instead of getting the fetch result as 1 2 3 4 ... n, I need the opposite, n ... 3 2 1 (nothing to do with a fetch using reverse order sorting) straight from the fetch request. I'm not sure it's possible? is there a CD gotcha allowing to re-order the fetch result before it is presented to the UICollectionViewDataSource delegate ?
2)Change the Index path/viewCell association in "collectionView cellForItemAtIndexPath:", Use (numberOfItemsInSection - IndexPath.Item). It creates several edges cases, as entries can be removed/updated in the view (hence numberOfItemsInSection changes). So I'd rather avoid it if I can...
3) adding new data from cell 0, ruled out for the reason I explained. There may be a solution: has anyone achieved a satisfactory result by setting a view offset? For example, if 20 new entries are added, then the content of cell 0 is moved to cell 20. So, we just need to tell the view controller to display from cell 20 onwards. Any image flipping or side effects I might expect?
4) download a big chunk of the data, and simply using the built-in core data faulting mechanism. But that's below optimal, because I'm not sure exactly how much I should download - user dependent - and the initial request (JSON+Core Data) might take too long. That's why lazy fetching is here for anyway.
Any advice someone facing the same problem could share ?
Thanks !