I always get stuck with managing rotation on iOS application, there must be some kind of efficient way to do it but apparently I haven't heard of it yet. My interface is too complex to be parametrized in InterfaceBuilder so I tried doing all these different things:
Build two interfaces, one for portrait and one for landscape, but I found it awfully tiresome to devise some methods that enable one view controller to keep up with the other, so when the device is rotated the second view controller knows where to pick up the story.
Change my views' frames manually inside willRotateToInterfaceOrientation:, but in this scenario my whole interface turns into a bloody mess quite randomly (while sometimes it does the job alright...)
What do you think best practices are? Where might have I gone wrong? What did I miss? Thx!
I always go for the second option and it has never let me down. If you do it right, you will have always the expected result. What I think it's happening to your application (and you call it bloody mess quite randomly) its because your UIView's will probably still have some autoresize definitions on the Interface Builder. Besides removing all the autoresizes I also uncheck the "Autoresize subviews" checkmark from the parent UIViews.
Just playing devils advocate to JackyBoy's comment, I think it depends on the complexity of your view. In lots of cases I have found it simpler to just use a landscape UI. The benefit for me is the ease of visualization. You know (more or less) what you are going to get without as much trial and error and it's easy enough to pass whatever data is needed along (i find that easier then dealing with moving UI components around programmatically). That said, I don't know if there is really a best practice. It's a do what feels best to you kind of thing, I think. Though if I had to guess Apple's definition of what the best practice would be then it might be to use the two views.
Oh, I should also add that you can leverage the 'springs' and such for components in a nib that can sometimes be enough to handle the rotation as well
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Been trying to find some tips on suggested approach for this and not having much luck.
All I'm looking for is to know what is the best approach to handle custom layouts for portrait/landscape modes.
I've seen some posts say in the storyboard add 2 views to the same ViewController and show/hide based on orientation change while some people suggest to use a totally separate ViewController for each orientation.
Which of this is the preferred method. I'm just starting my application, So I'd rather go for the widely accepted method than have to deal with complications later on.
Apple documentation still keeps talking about nib files and not storyboards in this aspect, so not being of much help.
My main focus is performance (I'm fine with having to code stuff instead of depend on the graphical interface for it). separate ViewControllers seem to keep the code in a clean way however if that involves populating views / clearing them every time orientation changes, seems kind of expensive(not sure if it is relevant).
Also if each scene in the application has 2 layouts then managing them I'm not sure how much of a pain it's going to be when the application grows big.
Please point me in a suitable approach for my case,
am not concerned about backwards compatibility. Just worried about the latest Xcode and ios6 if it matters for the decision
Thanks
I would say this really depends on the level of customization of the UI in portrait vs landscape. A large number of implementations I have done can be handled by either autoresizing/autolayout when switching orientation, or simply moving the elements yourself when the UI is rotated and the callbacks are fired. Moving the elements around should not be an expensive operation at all as it is a very common occurrence (again this depends on the complexity of your UI though).
I want to decide if it is better to use XIBs or to designs my views completely using code.
So far I have read that when you design your views on interface builder they are pre-built, so even if they use more memory the user feels everything is faster.
People say doing everything using code is harder but I find it to be just as easy, so I want to know if anyone has experienced some real speed gains when using nibs.
What have been your experiences, advice, etc?
Thanks!
You should be able to do both -- there are times when building a view programmatically is better/easier, and times when using a .xib is better/easier. Even if you only ever do things one way, you'll run into code that does it the other, and you'll need to be able to deal with that.
If you don't know how to use IB, then building your views in code is certainly easier. That is why you should learn to use IB. Once you understand IB, it's way, way faster to put together most of the view-based UI your app will likely need. IB helps you line things up, center objects, align base lines, connect controls to their targets and actions, etc. I think it's safe to say that everyone who uses IB effectively experiences "real speed gains when using nibs."
You should know how to use both. Performance differences between the two are negligible and should not be the reason that you choose one or the other.
Many people who are new to iOS development have the misconception that nibs (.xib files) are inferior to programmatically creating your UI and that if you use IB you're not a good iOS developer. That view is 100% wrong. IB is created by Apple and in use by Apple's developers to create their own Mac OS X and iOS apps. If IB (as a tool) is good enough to be used by some of the best developers in the world, it's probably good enough for most of us.
In practice I have found that a combination of the two usually fits the bill.
In my own apps I find that .xibs are great for laying out the basics of your views quickly and they allow you to iterate very quickly while giving you a preview of what your view will look like. It's also much easier to use auto layout in a .xib file.
Then when you need to do more advanced things like add fancy animations or move views around that is what IBOutlets are for. Anything that you put into a nib can be referenced through an IBOutlet. This allows you do then programmatically make your view come to life.
Lastly, you should fully understand what a nib (.xib) is doing automagically for you. You should understand what happens when a .xib's objects are unfrozen. There are many resources on the internet to understand .xib files better.
Also, learn how to use .xibs in an encapsulated way. For example, .xibs are crazy useful for things like prototype cells and they allow you to keep your code base modular (much more so than storyboards). Also, you will require less UI code in your view controllers.
Lastly, I always say that people should think of IB/.xibs like jQuery. It's going to save you a lot of time but the best developers still know how to do everything in javascript if they have to.
Good luck and have fun!
TL;DR version
Performance is not a consideration when deciding to use .xibs or not.
Use .xibs because they give you a preview of the view you are creating and they allow you to quickly iterate
In practice most apps will use a combination of both. You will programmatically add animations or move views around but the .xibs will be a starting point
Understand fully what happens when the objects in a .xib are unfrozen
You'll be more productive but be sure you fully understand what is happening behind the scenes.
I would always use XIB files unless there was a reason not to. This allows your views to be maintained easily in the future.
Some reasons for creating the views programmatically might be:
A control needs to be resized,
repositioned or otherwise altered
depending on something else
Controls
need to be added or removed
dynamically
There may be more reasons but there are not too many.
If you programmatically create views when there is no need you make it a lot more difficult for other developers to try to figure out what the view will look like and to change it.
If you build your views programmatically, you have control over the loading of elements. e.g. you could use lazy loading, and load secondary buttons, subviews, etc. a fraction of a second after the more important elements, allowing the key parts of the UI to come up faster. You could even animate some elements into position.
If you use IB, you get guides as to proper element spacings and positioning, but you could always copy the coordinates from IB into code if you aren't changing the design that often.
For simple UI elements, you will end up with more lines of code to maintain if you create them programatically.
IB and NIBs do a lot to optimise loading/unloading of views, but it is largely oriented to minimising memory usage vs. perceived speed for the user. For example, lazy loading if anything might make the app UI slightly slower, but it should make memory usage lower. This in turn could make overall app performance better on a large application, and is very much encouraged, but it's difficult to define "performance" in a narrow way. It's also difficult to say when you should or should not use IB - there will be some times you're much better off doing it in code.
One often overlooked element to the IB or not debate is development speed, especially if you have multiple developers. On a larger team/project you'll probably have some developer(s) who specialise more in the infrastructure, business logic etc. of the app and some developer(s) who specialise more in the UI. In this case, use of IB will make it easier for them to work independently, which should make overall development more efficient.
I view IB as a core part of the development platform for iOS development. It's not the right solution in every situation but not knowing how to use IB will be a real limiting factor.
Are there any good reasons why I should not use XIB / NIB files with an highly customized UI and extensive animations and super low memory footprint needs?
As a beginner I started with XIB. Then I figured out I couldn't do just about everything in them. It started to get really hard to customize things the way I wanted them to be. So at the end, I threw all my XIBs away and did it all programmatically.
So when someone asks me if XIB is good, I generally say: Yeah, if you want to make crappy boring interfaces and don't care too much about performance, go ahead. But what else could be a reason not to use XIB?
Am I the only iPhone developer who prefers doing everything programmatically for this reasons?
I think that Interface Builder is one of the biggest assets of Mac (and by extension, iPhone) software development. GUIs are visual; why not create them using a visual interface? IB is flexible enough that you can lay out an interface using its "generic" components, and then subclass them where necessary. Sure, if you have a unique interface you're going to have to subclass a view class and perform custom drawing, but you can also lay out your interface in IB and then easily use the inspector to switch the class to your custom subclass.
Honestly I think it's a spectrum of convenience. If you are comfortable writing everything in code then go for it. If you design your project well then it should be about the same amount of work creating new windows, etc. But I know that a lot of people aren't as comfortable with the GUI world so nib/xibs work well there.
I honestly find myself using XIBs as a base quite often and editing them with code to get the specific look I want. Personal preference.
For a specific con on that point, views can be difficult to configure after loading them from a xib. When you have conflicting settings between IB and code that can be nasty to troubleshoot.
Here's a question for the list. What is the performance hit to using a xib? I thought they were a plus because they don't get loaded into memory until you need them. That said, that load time is longer which will slow your program down. Thoughts?
One thing I found better about code is for the event connections on controls, when you search for uses of a method (message) you find them if they are coded and you don't find them if they were set in IB.
On the other hand laying out objects on a view is much easier in IB where you can see their size and positions. When you do that in code you have to guess at the size and origin settings and then run it and make adjustments, then run it again to see what it looks like.
When your application has some kind of "standard" views, go with the XIB. If you need real customization, depending on external content (XML...) do it programatically.
I started using XIBs and now it's all code, I find myself more comfortable this way. I had real problems with XIBs, and now writing the interfaces all in code really saves me time.
I save tons of time when dealing with UIControllers (UITabBarControllers, UINavigationControllers etc.) in the start up phase where all the navigation stuff is hooked up.
I just build X viewControllers with a accompanying XIB, throw in the stuff needed in IB, labels, images etc. This means that for almost any sort of app you can have a proof of concept up in a few hours. This is enough to justify spending some time learning the ins and outs of IB. Especially on the iPhone where you can have a ton of good UI ideas, but they all fail when they move from the Simulator to an actual device.
The best thing, in my mind, is to balance it out, if you find yourself using a lot of time doing the "change the frame 3 px -> compile -> ahh.. needs two pixels more -> change 2 px - compile -> ahh.. 1 more px" for something that could be done in IB, you will seriously start to waste time.
I start as above, but afterwards I often throw the XIBs away for custom stuff. The trick is to not spend hours on implementing versions of custom stuff in code over and over again, but figure out how it should be and do the custom stuff once:)
The XML content of a nib file is very complicated. This makes it extremely difficult to review changes or fix merge conflicts with a version control system like Git.
Interface Builder is a nice idea, but Bret Victor, in his talk "Inventing on Principle" and his essay "Learnable Programming," implicitly challenges Apple to build an even better IDE.
One idea, based on Bret Victor's principle: What if I could select a "Move Tool" in the iOS Simulator app that let me move a button in my app and then the frame code changed in the implementation (.m) file? This would be much better.
The 'info' button in Interface Builder shows me that there are dozens of 'Illegal Geometry' warnings, each one with the issue 'This view overlaps one of it's siblings.' Is this anything to be worried about? Will it stop the app being accepted by Apple? The errors are happening because I'm layering PNGs over each other when I make the interface.
It should be fine. I have an app with the same warnings that was accepted with no problems.
The issue is that overlapping siblings are not allowed if the views are not backed by Core Animation layers (default on the desktop). On the iPhone, all UIViews are backed by CoreAnimation layers, so the overlapping is acceptable. As stated in the documentation for UIViews (2nd paragraph, last sentence): "Sibling views are able to overlap without any issues, allowing complex view placement."
Not a problem, as long as you're aware it's happening.
Of course, there are probably better ways of doing things. If your images aren't going to be moving, it might make more sense to compose them into one larger image and just use that one. If they are going to be moving, it might make more sense to just add them programmatically.
But this is your code, and you'll have a better idea of what you're expecting than I will.
If the views are not opaque, keep in mind that you will copositing them together at runtime which will incur a performance penality. If these appear on a view that needs to scroll I would want to make sure that they are opaque or not overlapping, otherwise I would not worry to much.
I have been programming with the iPhone SDK for some time now.
I have not been using Interface Builder. This scares me a little. I know that in effect I may be 'fighting the framework' but I do not see it that way.
I find it very easy to just instantiate my UITabBarController in my app delegate, instantiate a UINavigationController, then push and pop view controllers as I go.
Naturally I do not have an extensive knowledge of how to architect an app with XIB files because I have never done so, however I do know the general gist of it, having built some Mac apps in Cocoa using NIBs. So I am not completely ignorant.
My question is whether there is an increase in development time when choosing to lay out UITableViewControllers and UIViewControllers using XIBs rather than programmatically instantiating them and then setting up the ivars.
As I see it, both methods still require you to subclass the view controller for customization which will probably occur for the majority of your views. As well, there are still manual classes required for delegates, and the process of connecting outlets from within the XIB seems comparable to me from setting an ivar.
Or am I missing some other major point?
Thanks!
Code takes much longer to write to configure UIs than IB does.
Plus, you can hand off design to designers and let them tweak the UI.
In the end they both accomplish the same thing. You should use either one depending on the circumstances. Most of the time writing the code to create and position views, and especially maintaining it down the road, will take much longer than using IB. In a simple app for the iPhone though, this might not be true and you'd be just as well off creating everything in code. Basically, you should know how to do both, and pick the path that involves the clearest code and quickest development.
IB shines when you're using it to actually lay out views; even two or three views can be a real hassle to lay out and configure in code. I do tend to use it for tab bar and navigation controllers, and sometimes for subcontrollers (usually only if I think the user is very likely to use it), but that's more just because I'm already there so I find it convenient.
With this new version 3 OS they're announcing next week, I'm hoping Interface Builder gains some of the flexibility it has in Cocoa, where you can add palettes for your own classes and even build up complex non-view data structures (by using custom palettes). We'll have to see, though.
Don't worry too much, IMO Interface Builder is a little over-rated too.
It's definitely useful for getting things up and running quickly, or if you have an app with a lot of screens that are tedious to setup, but you're not missing much.
For the uses you outline just doing things in code is fine, and possibly even a little easier to understand.
Laying out views, or custom cells though... then you get into a ton of font/color/position setting that quickly explodes into a lot of code, hard to maintain and tweak. Much easier to adjust what you want in IB in those cases.