UICollectionView VS UITableview - ios

I have an app which will show over a 1000 items, all of those item details are local ( saved via coredaata) and will ship with the app.
In researching the UI mechanisms to show those items, I am in between choosing uicollectionview or tableviewcontroller with a customized cell.
My question is : Which choice would be more efficient and provide a smoother UI in terms of
dragging?
which one can I customize to load out the 1000 entries I have only enough the provide a smooth scroll, and load more cells as needed?
Thanks.

Both approachs will handle 1000 entries easily if you follow the good practices of view/cell reusing. Additionally both APIs are very similar, so jumping from one to the other is not that hard.
The main difference between the two is how you want to display those 1000 items. UITableView has a couple of styles of cells stacked one over the other. You should not try to bend it to do any other kind of things too much complex than that kind of layout. UICollectionView is a much more powerful set of classes that allow to modify almost every aspect of how your data will appear in screen, specially its layout, but also other things. You can see UITableViews in almost every iOS application (for example Contacts or iPod), while UICollectionViews are more difficult to see (the grid in Photos, but also the coverflow in iPod).
So, if you need something standard like most table views in iOS I will choose the UITableView, but if you need more control over your layout, go with UICollectionView.

It's slightly unclear what you're asking, so I have summerized the advantages of both.
UITableView
UITableView is the base mechanism for displaying sets of data on iOS. It's a simple list, which displays single-dimensional rows of data. It's smooth because of cell reuse and other magic.
UICollectionView
UICollectionView is the model for displaying multidimensional data - it was introduced just a year or two ago with iOS 6, I believe.
It's also smooth because of the same tactics used in UITableView - cell reuse, etc.

Related

UITableView vs UICollectionView for list display

I need to display a simple list where each cell has a title and subtitle and an accessory view. Height of a cell may be variable depending on subtitle length. This was easy to display using UITableView. But I saw a more modern way is to display such a list is UICollectionView with list configuration. There are a number of videos on list configuration & diffable data source and number of tutorials as well on the same but what I am trying to understand is if Apple is telling developers to move to UICollectionView from UITableView (which some experts surmise is going to be deprecated given the new APIs). So my question is whether one should abandon UITableView to display such a list mentioned above, and if UICollectionView is really a replacement for UITableView?
Apple started killing UITableViews years ago, likely 5 or so. They're still here and still going strong. UITableViews will still work and there's absolutely no reason for you to drop them and replace them with UICollectionViews.

How are complex iOS screens made?

I'm trying my first steps in iOS development, and so far my app is going well. However, I've reached the point where simple UITableViews are just not cutting it.
For starters, I have a table view with two sections. I've implemented the method providing each section's title. But when I compare it to, for example, iOS's Settings screen, Apple's style (which I've seen implemented in other apps) looks much better, with better styling in the "section titles" and complex controls in the "table cells":
Now in my app, in some screens I would like to implement something similar to WhatsApp's settings screen. In this case, each "cell" does not have anything very noteworthy layout-wise, but I like the spacing between the different sections:
My last question is: when I am composing a cell, it is very clear to me how to implement a layout, its constraints, etc. Now imagine that I want to show a Table View showing a list of teams, and for each team I want to show the team players underneath, one player by line. It is not yet clear to me how I define layout contraints with an arbitrary number of elements. How would I approach doing this? Grid inside cell?
To sum it all up, my question is: are these screens TableViews with fancy styles and cells and more complex implementations? Or a different View that I am not aware of? Or even an empty canvas that they then compose "by hand"?
For context, I am developing with XCode 9, Swift, on a project with storyboards.
They are custom UITableViewCell cells (like the volume and profile avatar) or standard cell prototypes (WhatsApp settings are UITableViewCellStyleDefault with cell.imageView.image set.

When to use UICollectionView instead of UITableView?

I found that UICollectionView is like an upgraded version of UITableView introduced in iOS6, but when should I choose UICollectionView instead of UITableView?
There are still Apps using UITableView, if UICollectionView can do anything UITableView can do , why people still use UITableView? Is there a difference as far as performance is concerned?
Thanks!
That depends on the requirements. How the application flows determines which type of UI to integrate into the application.
People mainly use the UICollectionview for creating types of UIs with multiple images shown in a grid. This would have complex logic using UITableView, but with UICollectionview, it would be easy.
When using UICollectionview, you don't need to set buttons with tags or other things by getting selected items values. You can simply get -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath and in UITableViewDelegate:
`-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath`
You get the selected row instead of the item, so for creating grid or modified items, using UICollectionview is best.
For the listing details of each item, people use UITableView because it shows more info on each item.
Apple Docs:
UICollectionView Class Reference
The UICollectionView class manages an ordered collection of data items and presents them using customizable layouts. Collection views provide the same general function as table views except that a collection view is able to support more than just single-column layouts. Collection views support customizable layouts that can be used to implement multi-column grids, tiled layouts, circular layouts, and many more. You can even change the layout of a collection view dynamically if you want.
UITableView Class Reference
A table view displays a list of items in a single column. UITableView is a subclass of UIScrollView, which allows users to scroll through the table, although UITableView allows vertical scrolling only. The cells comprising the individual items of the table are UITableViewCell objects; UITableView uses these objects to draw the visible rows of the table. Cells have content—titles and images—and can have, near the right edge, accessory views. Standard accessory views are disclosure indicators or detail disclosure buttons; the former leads to the next level in a data hierarchy and the latter leads to a detailed view of a selected item. Accessory views can also be framework controls, such as switches and sliders, or can be custom views. Table views can enter an editing mode where users can insert, delete, and reorder rows of the table.
Here's my criteria:
If a UITableView can do it, use it
If a UITableView needs lots of code to do it or can't do it at all, use UICollectionView.
You have to consider the restrictions on UITableView before making a decision: It's a single column. And you can only customize the cells, but not section backgrounds and such. So if you have a straight-up list of things with no extra frills - that looks like a bog standard iOS view, basically - then use UITableview. If you have custom insets, or a border around each section, use UICollectionView.
I'm actually considering UICollectionView for all things simply because it's very expensive when you start developing your view as a table view, then later find out it can't do that one thing that you need it to do. 1st hand experience ;)
Edit after even more experience with the two: Disregard that last paragraph. UICollectionView requires a lot of boilerplate code to make it work like a UITableView. Use UICollectionView only when really needed. ;)
For simple lists and forwards/backwards navigtaion, use UITableView.
If you need a high degree of customisability, use UICollectionView.
Generally speaking, in software development, it's best to choose the approach which represents "The Simplest Possible Thing".
EDIT: As of iOS 14, UICollectionView can now do lists as well and is now the recommended approach. See this session from WWDC20 for more information and implementation details: https://developer.apple.com/videos/play/wwdc2020/10026/
According to my point of view main difference between collectionView and tableView is that
TABLEVIEW --> show list of items in only one column.
COLLECTION-VIEW -->show list of items in multiple column.
Hope it will help you.
If you choose UITableView for iPhone, make sure you have considered your iPad strategy first. If you want an iPad-specific layout, you may want that single-column layout to become a grid.
Although it's not required, I always use a collectionview. That way I can easily adapt how my collections are presented for differing resolutions. A plus is that it's ready to quickly add new types of cells when refactoring in the future.
I see no point of tableviews. It's very simple to use a collection view to represent a table. IMO.
From my personal experience the two elements should only be compared loosly.
TableView
A TableView is a UI element designed for showing data in a list format. There is certain functionality that comes as standard with a UITableView, such as:
Accessory View
Cell Selection Style
Editting Style (Delete and edit buttons).
The above elements enhance the usability of data when displaying and interacting in a list format. Such as viewing emails.
CollectionView
A CollectionView is a UI element designed for showing content using a custom layout (usually anything that isn't a list). CollectionViews improve functionality of displaying data in completely bespoke layout styles and also dynamically changing layouts on the fly. Some examples are:
Horizonal Lists
Photo Galleries
Thumbnail views
Carousels
Dials
Laying out elements on a map
etc.
CollectionViews also allow for multiple selections.
Conclusion
As you can see from the above, both have completely different use cases and are designed for enhancing the development and usability of their own specific data sets.
If you are looking at displaying anything in a list style with the followin interactions:
- Adding
- Deleting
- Re-ordering
Then a UITableView will simplify this process by providing the support straight out of the box.
Anything else, you should leverage the benefits of CollectionView as you have more flexibility.
Its totally dependent on how your data to be shown.
As mentioned by many above, if you require only single set of data and that too not complex, go for UITableView else use UICollectionView.
UICollectionView is customization friendly.
If you are dealing with multiple cell heights or so, then go for UICollectionView.
Both are depends on the requirements. Table Views also have support for a variety of editing scenarios. This support has not been implemented in the Collection View classes.
If you are converting from a Table View that relies on these methods, expect to do a little extra heavy lifting in the Collection View.
Collection View section headers can be placed anywhere within the view.
and UITableView don't need to set buttons with tags or other things by getting selected items values.
In practice, everyone uses UICollectionView that I've come across, when they only need a UITableView. "It's one-dimensional. It goes up and down. Why are you adding unnecessary delegate methods for layout AND data?". I once spent an extra 2 hours helping a startup find out why their UICollectionViewCell got squished because the owner, who didn't read the Animations manual, nor HIG, nor the UICollectionView guide, decided to use it and add variable heights and anims. Needless to say, he gave himself a headache and much lost time on a non-business-critical issue he could have avoided by simply using a table cell, since there's no extra layout delegate + Nib.
Let me get this straight, I am all for UICollectionView's when your data and display need it. They're very powerful. But in practice, most people I've seen have been using them on lists.
This brings up another flaw. They're also used on short, constant lists that won't change, ever. In this case, just make a Xib. Or write a custom view that stacks them. Why? Because you don't need the memory management for 5 sets of labels with a button or switch. If they might change, then yes, use a list. If you want physics, then UICollectionView works well with a some cool effects. But do you really need to add 5 delegate methods and a layout system for 5 labels that will never move?
Also, I'm not forgetting that iOS has a native stacking view now too. I can never get it to deform how I want, even though I'm quite adept at the 2D and animation systems, so I never use the built-in one.
All I'm saying is, define your requirements. Maybe you don't need either of these, if your UI isn't adding/removing items and refreshing itself. Or maybe you want to write a Card Game and throw them out virtually on a table, then use UICollectionView with a physics system for its layout guide.
Personally I think the UICollectionView can do most of the work which UITableview can do. well, at the same time, it's more complex to use.
I suggest you use UICollectionView as TableView just in case your manager change requirements in the future.
Based on our need we are choosing TableView or CollectionView.
Example:
For phone contacts tableView is best option.
For photo gallery, collection view will be best option.
I had this issue in my current project. Which to use. In my case it was simple really. I needed both. I needed my view to look like UITableView and also to change its change / layout. So, UICollectionView was used. I also use UITableView everywhere I don't need any extra customisation. Since UiTableView comes with a default layout that includes images and text - I use it for simplicity.
Based on our requirement we choose UITableView or UICollection view.
If we want to display images or items in grid type or if we need more customisability we use UICollectionview.
For listing each item with details and subdetails we use UITableView.
UICollectionView:
The UICollectionView class manages an ordered collection of data items and presents them using customizable layouts. Collection views provide the same general function as table views except that a collection view is able to support more than just single-column layouts.
UITableView: A table view displays a list of items in a single column. UITableView is a subclass of UIScrollView, which allows users to scroll through the table, although UITableView allows vertical scrolling only.
As per my view for Grid View display use UI Collection View.All other list view use UITable View

IOS: choice a UIScrollView or a UITableView

In my app I should create a view with a loto of informations;
these informations are divided in 4 section, every section can contain text, images lists ecc...
this is a brutal example...
Now I'm dubious to what type of solution to adopt.
In a my fast opinion a big scrollview is difficult to organize. And a big tableview with section is complicated to organize with code... What are your ideas?
UITableView is optimized for "reusable" cells, which is appropriate for scrolling in long lists.
Another benefit of using an UITableView, as others suggested, is that it only instantiate visible cells, so memory consumption is reduced.
In your case, since your content looks specific and non repetitive, I would suggest using a simple UIScrollView which is easier to use. (UITableView inherits from UIScrollView btw)
If memory/performance is an issue, then prefer UITableView or simply write your own logic to only instantiate views that are visible (by using scrollOffset for example)
EDIT:
On second thoughts, in your case, UICollectionView is surely a better candidate than UITableView.
Especially if you plan some day to do something like a 2 columns layout on iPad...
You should go with UITABLEVIEW, easy to manage easy to understand, more reusability and good memory management
If you have lots of content to scroll through, a UITableView might help you with keeping memory usage down.
When a cell scrolls out of sight, it gets removed from the view and kept around by the UITableView for later use (via -dequeueReusableCellWithIdentifier:). If you run low on memory then I believe that those invisible views (UITableViewCells) will get released. This basically means that your app will only keep views in memory that are actually visible. More will be cached, but can be purged any time if needed.
If you display a lot of data, and just add it all to a UIScrollView it will potentially use much more memory than if you used a UITableView. You might have to implement a similar mechanism to what UITableView does to remove (and potentially release) invisible views.
So, you can basically achieve the same effect, but a UITableView does a lot of that work for you already.
If you display lots of data (probably more than about two screens full) I'd lean towards using a UITableView.
This sort of thing is very easy to create in Interface Builder now with static cells; you can layout the entire interface visually and set up outlets for the cells (and/or their subviews) in order to configure the content in your view controller.

Objective C: How to implement a datagrid view (tables with multiple columns)

I am currently working on an iPad application that uses a table view to present data, I was inspired by the iTunes application in iPad that present it's data in multiple columns in a very nice and neat manner, and the most interesting thing is that during the portrait mode the itunes application displays data in 2 columns but when the user switches to landscape mode, it switches the display to 3 columns (since there are plenty of space to display data horizontally).
This is what i'm talking about:
but i found out that iOS SDK only supports single column for tableview (it would be nice to utilize the entire space provided on iPad screen to present data), i did some research and i found out that the best way to present data in multiple columns yet like spreadsheet style is to use datagridview instead, but iOS SDK did not provide any data grid view controls for iOS developers.
I found out over the internet some customized tables like:
AQGridView.
DTGridView.
and also the one from this:
http://usxue.is-programmer.com/posts/14176.html
and the one from this:
http://xebee.xebia.in/2011/04/14/building-editable-gridview-for-iphone-apps/
But sadly none of these ever met the requirements of the application i was working on.
Could you guys provide me some ideas or share some sample codes or links on how to display data in somehow-data grid view, to achieve similar effect used in iTunes application (as shown above).. Any form of help would be pretty much appreciated. Thank you guys!
The summary answer is, place multiple data "views" across in a single cell.
The more detailed answer:
Create custom views that represent the single cells you want. You can for this purpose make them resizable enough to work two across or three across (they will get loaded into 1/2 or 1/3 of the cells bounds).
Then make a custom UITableView cell, that can take two or three data items - load up an instance of the custom view previously created in the cell for each data item you have, placing them next to each other. You can have the cell do the view layout when groups of data items are added.
In the cellForRow code in the table delegate/datasource, you use your data source in groups of two or three (and report the row count accordingly) to pass along to the custom cell.
Sorry I can't share code, but I have used this technique before in other applications.
What's wrong with creating a UIView class to represent a single cell, and another that lays out an array of those cells in a grid? Put your grid view in a UIScrollView and you're about done.
UITableView is obviously a pretty complex class. Much of that is to make it very general, very reusable, and able to support a huge number of rows. Your class doesn't necessarily need to be that complicated -- if you have a fairly small number of cells, your "grid" could really just be a UIView in which you lay out cells in rows and columns. UITableView removes cells that aren't seen in order to save memory; you might need to do something similar if you have hundreds of cells, especially if they're large, but a few dozen probably won't require that.
In short, since you need a grid view for a particular use, you don't need to do all the extra work that would be required for a general, reusable solution.

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