Using a tabbar for controlling the tableview data in iOS without using storyboards

Question

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.

Answer 1

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.

Answer 2

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.