iOS无法在View Controller中删除IBOutlet

Question

First, I want to apologize if my question isn't asked properly or if the answer is obvious, but I'm learning iOS development and I have some difficulties with specific terms because I'm French.

My application has a table view controller containing table view cells, and all of those contain a label and a switch. It's made for my home automation: when I tap on a switch, it should switch on/off my lights or TV by sending an SSH command to a Raspberry Pi.

So here is my problem: I followed a tutorial on Treehouse to add an action to my switch, but when I an action from storyboard to the view controller, then drop in between @interface and @end , nothing is generated, and I would like to know why.

PS: Can someone tell me where all my objects contained in my view are declared, because when I right-click on my storyboard and then open as source code, it's an XML file. Why they are not in Obj-C?

Thanks.

Answer 1

Objective-C is a fully reflective language: from the string name of a class and the string name of a method you can, at runtime, create an instance of that class and call that method.

The interface builder is a design tool. You lay out views and give them properties. It's essentially a drawing tool so just like Photoshop or whatever its documents are pure data . It happens to store those in XML.

The data is parsed and converted into objects in the same way that a PNG file might be parsed and turned into pixels. So no code is generated . This is not like Visual C++ or one of those that sort of hacks on a design tool by automatically generating code. There is no code. You can't see it because it never exists, anywhere.

As it happens the interface files are currently a particular format of XML. They've been other forms in the past. It's undocumented and not to be relied on directly. Just use UINib to read them, or rely on that happening automatically through the main interface file you've possibly specified in your Info.plist.

As to the tutorial, it's difficult to answer without seeing the project. Is the view controller you're dragging to definitely the type named in the interface file?

Answer 2

If your table view is set to be dynamic using prototype cells, I don't think you can drag a component from the prototype cell onto your ViewController. Instead, you want to create a custom table view cell class. Then you would assign your prototype cell with the switch to use your custom class. Finally, you should be able to control-drag the switch onto your custom cell class and create an outlet property. This will give you a reference to the switch for each cell. In your view controller, you can then obtain the cell object and then get the switch property. The same goes for adding an action, you can control drag the action to your custom cell class.