I have a working UITableViewCell. Now I have a different cell I need to make which is exactly like the previous one - but has a UIWebView instead of UIImageView.
I was thinking of doing a different xib for the cell, but the thing is they have tons of code and logic in common (for the rest of the controls)
What is my best approach in this case?
You can make a parent class: put all the common code there, then make 2 subClasses of this superClass, they'll inherit the superClass code, and put there all the code and objects specific for each of them
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Are there any use cases where one would better use UIScrollView instead of one of its two subclasses UICollectionView and UITableView?
I saw one used in a piece of recent code and cannot think of any justifiable reason to use it instead of, in that case, a collection view.
I have a lot of common logic, therefore all my viewControllers inherit from BaseViewController, BaseDetailsViewController or BaseWebViewController. The last two inherit from BaseViewController which inherits from UIViewController. The problem is I cannot use tableViews with static cells because my BaseDetailsViewController is not inheriting from UITableViewController.
I'v never used and inherited UITableViewController because the same could be achieved by inheriting from UIViewController, wiring it with an added UITableView and having implemented datasource and delegate methods. Therefore for the form type screens (SignUp or other data input screens), I use my own BaseDetailsViewController which adds nice and handy methods (input validation, custom styling, scrolling keyboard, handles input field navigation and etc.)
Using UITableViewController has two real benefits: 1) keyboard scrolling (if you use text fields) and 2) easy creation of your form UI elements inside on screen. The first benefit is irrelevant for me, because I'v already have my own implementation of this stuff inside BaseDetailsViewController. Regarding the second benefit, I'm creating my form inside scrollView which gives a lot of flexibility but it's a little bit more effort (especially when need to update the screen). Therefore I heard some guys implemented their own UITableViewController and then made it to inherit from their BaseViewController. Therefore I started to dig into this approach.
So far I'v came upon these two approaches:
Recreate your own tableVC. Not clear how to make it work for static cells. Currently my demo app crashes if my ReplaceTableViewController is not implementing numberOfRows and cellForRow, and not shows static cells if I implement them with dummy content.
method-swizzling. Not clear how to change class inheritance by injecting baseViewController inheritance for UITableViewController, thought still not clear which methods are needed to be added.
Anybody tried and want to share?
UPDATE I'm not using storyboards as I promote clean MVC - every screen as component should have its own Model, View (Xib), and controller, all stored in separate files to eliminate merge conflicts of multiple devs in large app projects (30+ screens). And therefore container view with embedded segue to tableViewController is also not an option.
UPDATE2 In case anybody would like to take a look why and how I'm doing this, here's a link to my open source template based new project generator framework which I started to publish recently.
Static cells need a UITableViewController. You can't changed this right now.
But to use static cells in a UITableView outside of a UITableViewController you can use a ContainerView in your Non-Table-UIViewController, where you place a real, separate created UITableViewController working with those static cells.
To share common code between multiple view controllers, inheritance is not that best solution as you found out by yourself while subclassing UIViewController vs. UITableViewController. You can use some sort of composition for sharing code or - especially for objective-c - categories.
Categories are not allowed to have its own properties, but there are workarounds possible with objc_setAssociatedObject.
Another approach would be to not use static cells, but dynamic cells in a UITableView with DataSource-Delegate :)
As you see in my screenshot, to reuse a special TableView with static cells, i place it in other ViewControllers in a ContainerView. Since you are not using storyboards, i am pretty sure that this can also be done by code without storyboard.
I've got a static TableView that now needs to become a dynamic TableView, because other views need to be placed around the ViewController, and this can not be done using containers in my case.
The question is: how do I efficiently convert the table view from static to dynamic?
I'm aware of having to change the inheritance from UITableView to UIViewController and add the plus the delegate methods.
But how about all of the Table-Sections: I have 3 sections with 6 types of cell in the static table. Do I really need to subclass UITableViewCell for all of these cell-types and deal with everything manually, or is there a more clever way to do this?
You really can't just convert between the two. By merely implementing some of the tables delegate methods, like cellForRowAtIndexPath:, you loose your static content. That being said, the table should be dynamic the entire time. This way, you can define logic to determine whether or not it should show the content that you originally added statically, or the new dynamic content.
Additionally, you don't need a view controller to implement the delegate/datasource methods. If you already have a subclass of UITableView, that's fine. You can set it as its own delegate/datasource, and implement those methods within the subclass.
And to answer your last question, no there really isn't a better way to do that. I recommend that you create one base class that subclasses UITableViewCell that implements everything that the cells will share, and then implement the individual changes in subclasses of this base class. Using multiple cell subclasses in a table view sounds a lot worse then it is.
I have a UITableView, with 8 differents type of cell. Those custom cell have some design in commom (like a upper left icon, a title, a subtitle...). However, under those common features, each cell is different. In order to have less to maintain, my 8 cells inherits from a default abstract cell with the commons IBOutlet.
Now my question is : what is the best, most proper way to do this?
At first, I thought of using registerNib:forCellReuseIdentifier: but this means 8 different xib. In this case, if one of the common design feature change, I would need to go trought all 8 xibs to change the same thing. I thnik it's not very productive and clean.
I thought also of registerClass:forCellReuseIdentifier: but this methods does not create the cell with a nib, so I would need to do everything programmatically.
The solution could be have one common xib, different registered class in the tableview, and those will be responsible for using their own custom design. But I can't see how to achieve this with those two previous methods.
I would use a single nib file with 8 different UITableViewCell subclasses. You should be able to use registerClass:forCellReuseIdentifier: and inside the class (which subclasses UITableViewCell) you make use of the nib file. If it is not clear I'll try to provide some code.
(screenshot below helps explain what I am trying to do)
The idea behind this is that I have a UIView, with various different UI elements inside, for example, let's say I have a UIView, and inside there we have a UILabel.
Now I'm wanting to duplicate the UIView (with the label inside) BUT somehow after that I need to perhaps make a change to the label, e.g. change the text property.
The reason I need something like this is so I can structure the UIView with everything I need in it looking nice, but to actually have different data with different copies of it.
I'm not certain this is the best approach, but it's the only one I could come up with. If anyone has any ideas on how to do this, or any ideas on a better approach I'd really appreciate it. A lot!
I personally think the best answer is to create each view separately and configure it as needed. You can make a method that just configures new UIViews to look the same, and pass each view through it.
However, if you really need to copy a UIView, you can archive it, and then unarchive it:
id copyOfView =
[NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:originalView]];
UIView *myView = (UIView *)copyOfView;
[self.view addSubview:myView];
If you have a bunch of these, make sure you're using the Instruments time profiler to check your drawing efficiency.
This is a very natural and useful thing to do. What you're looking for is a container view controller. Put your reusable "cell" into its own view controller and its own nib file. Then, in your parent view controller, use addChildViewController: to add as many of these as you'd like and configure each of them. They can each have their own IBOutlets that you can use to modify the contents.
This is very similar to the pattern used by UITableView and UITableViewCell (it doesn't use "child view controllers" specifically, but it does use this pattern).
For full details, see "Creating Custom Container View Controllers" in the View Controller Programming Guide for iOS.
Note that Storyboard includes a "Container View" as an option in the object templates to make this even easier.
If you want lower-level access, you can also do this by hand using UINib to load the nib file and wire its outlets (and this is how we used to do it before iOS 5), but today I would use child view controllers.
If you have only one label inside it the obvious solution is to have a custom UIView subclass with that label added as a subview. Everytime you need a new view you make an instance of your custom subclass and set the label text. If you have multiple things to set, some of which are common to all your custom subclass views you can use the prototype design pattern, it's pretty straight forward to implement.