I'm trying to create an app where multiple lists can be switched between using a button. Does anyone have any advice on the best way to do this, preferably using storyboard (my Swift skills leave a lot to be desired)? Right now I only have one list (a TableView) which is contained in a Container View, along with two other regular Views, one at the top and one at the bottom of the Container View, with the TableView in the middle. I want to have a button in the top regular View that switches between multiple TableViews. I want the number of TableViews to be dynamic, starting with one, but then the user can add additional tables as they need. Any advice on how to set this up would be greatly appreciated! Is it even possible to create a prototype TableView? Is that the way to go here? I've found a couple of Answers on Stack Overflow regarding multiple tables on a single screen, but these lists wouldn't be on a single screen, they would only be viewable one at a time: if you want to see the second list, you have to press the "Next List" button (in the View at the top of the Container View), and the first list disappears and is replaced with the second. Thanks everybody!
Don't change table views, change datasources. Use a single table view as you have it, and one array for each mode that the table is in (call those arrayA and arrayB). Another array-type variable -- call it theModel -- should be set to point to A or B.
The datasource methods will answer the count of theModel, and get values for the cells from theModel. When the user presses the button...
self.theModel = (self.theModel== self.arrayA)? self.arrayB : self.arrayA
self.tableView.reloadData()
// everywhere else, use theModel as the datasource
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New to Swift. I am trying to write a recipe-sharing app for fun. One of the features is to let users create a new recipe. On this page, users should be able to give an intro to the recipe to be created, upload an image THEN add a LIST of ingredients dynamically (as we have no idea how many ingredients in total beforehand).
I have created a UIViewController, which includes a UIViewTable, an image view and a "add another ingredient" button. I have created a class for the ingredient. And when the "add" button is pressed, a new "Ingredient" cell will be added to the table. However, I found that adjusting the UIViewTable height dynamically is quite hard.
I want my table to adjust its height according to the number of cells (rows). I haven't found much useful info online.
Or maybe I should've not even used this structure. Instead, just use UITableController (The entire page is a table)? But I got confused that some of the elements (image view, submit a recipe button, recipe-intro textfield etc) will be only created once. Why do I bother making them as prototype cells and add them to my view programmatically?
Thanks in advance!
First of all, welcome to Swift!
You put a few questions together, I will try to answer them one by one. Let's start with the simple stuff.
Don't try to change the height of UITableView based on the number of items. If you want to achieve similar functionality, take a look at UIStackView. Set fixed size for the tableView, ideally with constraints using auto layout.
UITableView is supposed to fill specified space and scroll items inside or show cell on top if there are not enough cells to cover all space.
UITableView is highly optimized to scroll over huge amount of cells as the cells are reused on the background. If you are new to the iOS world, take a look at this function https://developer.apple.com/documentation/uikit/uitableviewcell/1623223-prepareforreuse it can save you hours of debugging (I have been there)
UITableView vs UITableController
UITableController can save you a few lines of code, but using UITableView inside of UIViewController can give you more freedom and save you refactoring if your app is likely to change in the future. There is no specific advantage of UITableController
If you want to provide the extra elements (image view, submit button, text field etc), you can use several methods and this is where the UIViewController with your own UITableView comes in handy.
You can put some buttons, like a plus icon or "Done" button into the navigation bar, as the native Calendar app does.
You can put the static content (intro text field, image view) above the table view (visible always). Use constraints to place the static content on the viewController.view and constraint the table view under your static content. The table view will take less space on the view keeping the space for your content.
Insert your static content as a table view header (will scroll out with the content). Search "HeaderView" here on stack overflow to see how to achieve that.
Place your content over the tableView. If your button is small (rounded), you can place it over the tableView, eg. Twitter uses this for a new tween button.
Hope this answer your questions. Cheers!
I am writing a Swift app, and on my main screen I have a long scrollview with several regions of content in it (upcoming events, announcements, and then featured products, and finally some basic info). So it's this really long scroll, and you can swipe down to the bottom.
So visualize 4 boxes, if you will, stacked vertically.
The 3rd box shows featured products. This can be anywhere from 1 to 30 items, depending upon any filters the user has in their settings.
My first try was using a UITableView for region#3 inside of this parent scrollview, but the problem is it only shows the first few items/rows and then the rest you scroll inside the table (which is the default/natural behavior of a table, right?). Unfortunately, the requirement I have is that the inner table can't scroll - it needs to display everything at once and you have to scroll (in the main UIScrollView) to get to the bottom (not scroll inside the inner uitableview scroll). Also, everyone seems to say don't use UITableView inside of a scroll.
So how do I create some sort of list where I create one template (like how you would in a xib/tablecell, and then assign a data source to it, and then repeat down without scrolling? Should I use a tableview after all, and just make the height of it very high and turn scrolling off?
Do I somehow instantiate xibs in a for loop and assign them dynamically to some view?
Thanks so much!
Sounds like you want a Table View with Grouped style. That would make it fairly easy to keep your "4 boxes" segregated, and your "3rd box" would simply be 1 to 30 rows in that section.
On note: you don't want to have a "very tall" table view - or any other type of view, for that matter. You want to allow iOS to manage memory for you, and to load and display only those parts of your content that is visible at any one time.
In other words, use a table view like its designed to be used :)
This question maybe already asked in stackoverflow. But, I did not get any clear idea to my scenario.
I have a viewcontroller (Say, MyViewController).
I have a scrollview(Say, MyScrollView) and I have N number of views (Say MyView1, MyView2, ...) in it.
Those views can be scrolled horizontally. Refer the below image for more clarification.
This image was taken from here.
So, the red area is the scroll view that holds multiple views which are yellow color.
Scenario:
I want to call API's for each view, when the API calling and parsing data occurs, I need to show some loading activity indicator in the views. After successful parsing, I need to update corresponding view with UITableView.
Questions:
In my case, the number of views may vary from 3 to 6. Should I maintain 6 separate UITableViews and UIActivityIndicator's?
I tried with three pointers like left, middle & right to hold reference of tableview and activity indicator. But the problem is, before the first three pages are loading, if the user goes to the fourth view, this system will collapse with so many conditions.
Suggestions needed. Confused!!
I think you have to use UIPageViewController with UITableView. it will solve your problem.
Dont know how else to explain this but basically im using a uitableview to load data(core data) and have basically limitless lists and items. for instance list1 is food contains candy, starches, meat, and meat may contain beef, chicken, etc. if i click through the tableviews and get to chicken, how do i use the back button to go back to previous. I am just using "reload data" instead of multiple tableviews in storyboard. is there a better way to do this???
I started to set 3 values prevparentlist, subparentlist, and parentlist. but end up losing prevparentlist when you go to deep and it will only back up one level....didnt think this through.....please help
You just don't easily "reuse" tableViews.
If the storyboard gets too messy in your opinion the best way is creating a custom viewController (including XIB), set the original NSManagedObjectContext to it (as property) and also provide a NSPredicate which meets your criteria.
Then you'll push that viewController into your navigation stack.
ARC will take care of releasing the viewController and corresponding view if you setup the properties correctly.
I think this could be easily solved , you have to keep and int value and that keeps on increasing with table view did select and which will decrease on pressing back button. Depending on the int value you can load the table view data.
I am building an app which mainly shows a tableview. In this tableview I have some custom table rows. The table rows are filled with data received from the server. I receive multiple kinds of data from the server. I will store it in arrays.
For example, I've got three kinds of arrays. Each is filled with different kinds of data received from the server. See below:
(NSArray*)carList_
(NSArray*)motorcycleList_
(NSArray*)bicycleList_
The actual program that I've got now, only shows the carList in the tableview. Foreach car in carList, there is a table row.
The thing that I've in mind to do is a little bit tricky. I want to add a tabbar at the bottom of the screen with three buttons. When I press the first button, I want the table to be filled with the carList. When I press the second button, I want to fill the table with the motorcycleList. And when I press the third button, I want to fill the table with the bicycleList.
As you can see, I will use the same tableview. I will only refill it with the data I want to see. Is this allowed in iOS? Cause I read something about that the tabbar is for multiple views, and I only want to use it for changing the data in my table. Only the fourth button I've planned for future development will open a new view. If it is not allowed, what is a good alternative do do it? Buttons maybe? I searched the web for what I want to do, but it seems that my idea has never been used before, I think my idea is not allowed in iOS.
At this moment I've a initialViewController (with almost no code cause it is used only to initialize some things of the server. It acts like a splash screen) and I've got a rootViewController which does the works. In the rootViewController I've got my Table with Table rows and it has the different arrays of data which are retrieved by a method that is called when the rootViewController is loaded.
I am programming without Storyboards, because I'd like coding and I want to understand how it works 'underground'. What is a good way to implement the tabbar if it is allowed what I want to do with it? I don't think a standard tab controller will work, because I am working with only one view.
Of course you can use the UITabBar solution. However this might be not very useful and this is not the idea behind the UITabBar. You can instantiate the same TableViewController vor each tab. In this case you can use the same class but you have up to the instances of this class when the user cycles through the tabs. This will be obvisously a waste of memory.
Your descriptions sounds like a UIToolBar with a UISegmetenControl in it might fit your needs better. You can also place it at the bottom of the screen and you will need just one TableViewController for your data.
UISegmentedControl is designed for switching between different data representations. It is also commonly used for switching between table datasources. But it often appears at the top of a view. Take a look at Top Charts tab of App Store app.
Tab bar is designed to present different views for each tab. Here are progress steps to achieve your result:
Use different instances of table view controller for each tab
Configure each instance for displaying one particular array, depending on tab position
Keep arrays in external (outside table view controller) storage, instances should have an access to it
It's better to preload data, while user is examining an active tab. Hence, load data outside of table view controllers, possibly in AppDelegate. Use notifications to update table view when data are available.