I have designed a ViewController in my Storyboard and I have adjusted all of its constraints respectively.
Now, I would like to animate most of these constraints.
So :
I should define them again using Swift codes
and write some codes to do the animations.
But it is very annoying to define the constraints again in Swift code while I already have them in Storyboard.
So, I was hoping someone could introduce me an easy way to achieve this automatically.
No, there are no built-in ways to render the IB constraints into Swift code. You could iterate through them and grab all their properties and do something like that, but that will get messy. There are too many different ways to create constraints programmatically, and even if some automated tool existed, I bet the code wouldn’t be very elegant. (As a general rule, tools that generate code programmatically don’t result in very good code.)
I wonder about the whole concept. We often animate constraints generated by IB without going through all of this. The typical approach is to give these IB constraints #IBOutlet references and then you can programmatically change their constant values and then put the call to layoutIfNeeded in the animation closure. Or, if you must, you can deactivate them (again, using the outlets) and then do whatever animation you want and, if appropriate, re-activate those constraints later, if needed.
But we can’t advise on to how to best achieve your animation in an IB view with constraints without more details about the nature of the animation.
But this is an example of how you can animate change the position of a view that has constraints defined in IB: https://stackoverflow.com/a/28329399/1271826
Related
The output of this tableview not appearing correctly.what is the reason to come like that
So the tableView that you just drag into a view will have default properties associated with it. When you run it on a phone/sim it doesn't actually have the 'Table View' heading (that's just there to make it easier to design the storyboard), it'll have a white background with no rows and will look like there's nothing on the screen. Furthermore it may not even be at the location you placed it at depending on how the constraints default when rendering the scene.
It seems like you have a little to learn about how this works. When creating a new storyboard, generally speaking you associate a ViewController class to it. Assuming you have dynamic data to display on the table, you connect references to the tableView to the class, then you need to assign a delegate to the table and then implement the protocols. Then if you have custom cells, it adds a little more to do. Theres several great tutorials from Apple itself on how to do all this in swift.
If you just want to see how the table would look; in the storyboard itself you can create prototype cells in the table and design it out that way.
Either way, make sure you read about constraints and how to make it look right when rendering on a phone. Just dragging things onto the story board does not mean that when you finally run it, it will look exactly as you designed it. You need to specify how components align relative to each other, which is essentially what constraints do.
I have a custom subclass of UIButton that I want to re-use in multiple projects, some of which use interface builder and storyboards, and some of which may not. It involves setting the button's frame in several places.
If I add
self.translatesAutoresizingMaskIntoConstraints = YES;
in the initialization, everything looks and works right, however, I get:
Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints)
Will attempt to recover by breaking constraint…etc
logged to the console. However, if I set
self.translatesAutoresizingMaskIntoConstraints = NO;
none of the button sizing works and the button is completely broken.
Is there a way I can suppress the error since it seems to degrade to the right thing or can I somehow manually remove the offending constraint?
I've tried dumping the constrains after the button is initialized, however, it does not seem to contain the constraint AutoLayout ends up breaking.
Edited: Below are links to a sample project and then my button code. It works great when auto layout is turned off in the storyboard, however, when auto layout is turned on, the buttons seem to position at the origin (seems to be because when initWithCoder is called, the buttons don't have superviews or any position information).
http://www.kudit.com/dump/KFB.zip
http://www.kudit.com/dump/KuditConfirmButton.zip
Your guess is correct, in that when the buttons are initialized from the storyboard (using initWithCoder:) the frame is zero - this is expected for views using autolayout - frames don't get assigned until later on.
I have your sample project mostly working under autolayout by creating a boolean ivar called hasSetup, which get set to YES inside the setup method. The setup method doesn't run if the frame is zero. I also call it again from layoutSubviews. This gets around the not-working-when-using-autolayout in storyboard problem.
The various layers still aren't the correct size though. You may want to look into resizing them from layoutSubviews.
You also can't use setFrame under autolayout - you need to make sure any constraints on your view (like the sizing constraints from the storyboard) are adjusted instead. It's going to get quite messy dealing with both possibilities.
They look really good though - hope to see them on GitHub when you've sorted these problems.
I have made a pretty little UI on storyboard but I'm quite new to XCode and Objective C (coming over from Java) and I'm having some trouble adding functionality. I know that I should make a subclass of UITableViewController (storeTableViewController) and set the class of the storyboard controller to that. The problem is that when I do that all my hard work in the storyboard is erased, and I can see where the code is conflicting with the showing of my UI (for instance, the tableView:numberOfRowsInSection returns 0 always), and I think that with enough time and patience I could program the UI, but is there any way that I can use all this work that I've done on the storyboard and still be able to add functionality? I want to set a text box at the top to be the first responder as well as be able to change an image and labels on command programmatically.
You should probably use IBOutlets. Connect the StoryBoard UI Object to IBOutlets and you can modify the properties of the UI objects from the code
You can declare IBOutlet link this
IBOutlet type variableName
Check this tutorial video which will help you a lot.
Video Link
I use the storyboard as a canvas. I plug in the outlets that I want and all the little details and then I go around and built the classes. That being said, you need to declare a urtext field outlet (depending to what you want it to do) then add the delegates necessary and allow it to perform on selector. Then you can declare the function. Linking it in storyboard is easy by control and drag.as far the image you can use an uiimage and declare its function and how it changes depending to what the changes are the code varies. My suggestion is to take screen shot of your storyboard and post it with your question so I/ we can help you with the code. But as far as your question goes I hope this answer satisfies you. Happy coding.:)
With the introduction of storyboard, I wouldn't select to create a .xib/.nib when I create a subclass of UIViewController, because I can just drag out a viewcontroller in interface builder and assign it to the new class.
So, with storyboard, when would i need to use the .xib/.nib file?
Thank you.
Storyboards don't completely remove the need for NIB files. One common example is when creating subviews to go inside a UIScrollView. You can't create the subviews separately in a storyboard; instead you have to create separate NIB(s) for the subviews and attach them to the scroll view programatically.
In fact, on almost any occasion where you have a need for subviews which change at runtime you'll want to use separate NIBs.
Storyboards are great for certain kinds of apps, but for anything even remotely complicated the old way works very well still. An additional benefit is that they co-exist nicely. You can put placeholder views in your storyboard and fill them programatically with NIB-defined views later on.
I guess, storyboard contains the .xib/.nib files for all your views. It present relationships between them and helps you to avoid confusion if you have a LOT of views. Also it saves your time and nerves when writing code.
I have tried out storyboarding lately and I do have mixed feelings about its use:
Pro's
Convenience: You might have to write much less code. So you can for example show a static view without having to write any code.
Overview: You can quickly see how the ViewControllers relate to each other
Efficiency: For the simple use cases I find the Storyboarding much more efficient than "the old way".
Example 1: Editor > Embed In > Navigation Controller and voilà, no more instantiating and configuring is required.
Example 2: You can make "Prototype Cells" for TableView which speeds up the creation of static table views dramatically. AFAIK this is not possible with nib files
It's cool :-)
Con's
I find that the re-usability somehow suffers with storyboards. Although I can segue to a given ViewController from multiple points, it is still limited since in one case I might use the VC as a Popover and in another as a Master-ViewController.
Assuming that you are working in a big team and different people are changing different parts of your application, having one monolithic storyboard which you then have to merge might pose a big problem team-work-wise.
I really would like to have some mechanism to include or reference existing nib files into the storyboard which is currently not possible.
So considering these points I still find storyboarding very appealing but it makes sense to combine both approaches which is not really a big deal. Additionally, this technology it is still quite new so it might improve in the (near) future.
If you use storyboards, you generally won't need to create separate .xib files. You can still use a .xib file if you want to -- it might be useful e.g. if you have a particularly complex view that you'd like to configure by itself. Most of the time, though, there won't be a need to do that.
Is it possible?
I have a UINavigationBar that I'd like to have an 'edit' button next to the 'back' button. From what I've read you can only have one or the other, which makes no sense as they are separate properties of the navigationItem object(backBarButtonItem and leftBarButtonItem).
I'm assuming you have to somehow insert a custom UIView into the UINavigationBar. I'm looking into this option and if no better solution is given then I'll outline this method.
The short answer is:
Yes, you have to add your own UIButton views (or other UIControl subclasses) to the navigation controller, yourself. So, ignore the custom *ButtonItem properties and roll it yourself.
A little more involved answer is:
Apple makes it very easy to follow their HIG guidelines, but you're on your own if you want to break them or customize. In this case, only one button is allowed, because the actual hit region is bigger than the size of the displayed button--much easier to hit from a usability standpoint.
Extraneous:
btw, there is a subtle distinction between left/rightBarButtonItem and backBarButtonItem. left/right is specified on the current UIViewController. However back is specified by the previous UIViewController.
Using a custom view is indeed your only option here. The UINavigationBar is not terribly flexible. What you will need to do is create a UIView that contains UIButtons. Be sure you realize that if you use a custom view, you gain none of the automatic behaviors of the backBarButtonItem; you have to create your own IBActions, and the graphics for the buttons as well.
On a related note, I'm not sure this is the best idea. It's usually wise to stick to Apple's UI guidelines; is there no where else you can put the edit button? The right side of the bar, for example?
While #Kelvin's answer works for pre iOS 5, if you're using iOS 5+ there is now a leftBarButtonItems array property. Note that you also must set leftItemsSupplementBackButton to true.