I assume this is going to be a very basic question, but maybe somebody can help me. I've come to iPhone SDK from a C# .NET background.
I would like to know if there is some mechanism similar to what is called in ASP.NET "UserControl" which encapsulates logic and interface. It would be desirable to launch "events" too.
I'm trying to design something like a common header for the entire application, which shows different types of buttons depending of the view where it is placed.
Normally Objective C will support only single Inheritance.We can achieve multiple inheritance
through Delegates called as protocols(user defined).i think it will help you when you google based on this(user defined protocols in iphone sdk).
First of all thanks for your contribution. I realized that I was looking for something different: The views (yeah, I know there were here since the beginning).
I've realized that when I allocate one of my controllers by default it tries to load the xib with the same name. Therefore, I can design the view on the interface builder and then load it on another view as a subview (that's similar to usercontrol concept).
How to make the view adjust to the desired size?:
Controller *controller = [[Controller alloc] initWithNibName:nil bundle:nil];
controller.view.frame = CGRectMake(100, 100, 200, 200);
[self.view addSubview:controller.view];
The only missing here is how to comunicate the view with the subview, but I supose that can be made with a reference to the parent.
Thanks a lot
(PS: I'm going to check the answer as correct just for close the thread. I don't know if this procedure is the best or has enough quality)
Related
Currently I am making a game for iPhone, and want each level to be on a different uiviewcontroller (I have tried putting them all on the same view controller, but this just makes it jumpy). However, I need a way to get a high score in the level's view controller and send it back to the menu view controller. I am using the code:
SecondLevelViewController *screen = [[SecondLevelViewController alloc] initWithNibName:nil bundle:nil];
screen.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
[self presentModalViewController:screen animated:YES];
[screen release];
to get to the viewcontroller and
[self dismissModalViewControllerAnimated:YES];
to get back. I am familiar with NSUserDefaults, which are what I am using currently to get high scores. However, I know this code resets the level's view controller, that is still fine and even great because i want the level to reset-- but if just i could get data back that would be helpful.
Please put things in simple words, because I am very new to programming.
Thanks in advance!
Steve Becker
PS I am using xcode 4.0...
--------------------------------------------ALSO!!!-------------------------------------
The code I am using, I can only figure out how to get transitions "FlipHorizontal", "CoverVertical", and "CrossDissolve"...But I have seen many other cool transitions on the iPhone--like the page corner flipping like a page in a book. If you know how to do these other transitions, please tell me!!!! Greatly appreciated!!!!!
It's much more standard to have all of the levels on the same UIViewController unless the logic is so different that it's like playing different games. However, you could use a whole slew of different methods to achieve this. For example, you could use the NSNotificationCenter, NSUserDefaults, or a plist.
You will want to use delegation or NSNotifications for this.
Think about the different view controllers like the mafia: every view controller is operating on a need-to-know basis.
Look at this answer I gave before.
you could also use a singleton class to modify and access the sharable data in any class of your projects,
Here is the good SO post on singleton class in objective - C
Singleton shared data source in Objective-C
Edited:
What should my Objective-C singleton look like?
Edited: for Curl page animation : below is the link to blog tutorial and the source code.
http://blog.steventroughtonsmith.com/2010/02/apples-ibooks-dynamic-page-curl.html
I'm wanting to make a multiview app with 5-6 different screens and a data source to store user information. I've never made a multiview app before, and I have a good idea on how to start, but I'd like to hear some recommendations on "structuring" your app to properly support this.
A very simple analogy could be going about making a background color on a website... You could either use an image of a solid color or simply use the background-color style. Both get the job done, but using the style is a bit easier/more efficient.
I just want to make sure I'm starting off on the right foot. Should I keep all my functions in one class' .m/.h file? What's the best/efficient way to go about different screens?
Thanks, and I'll definitely try to help others out once I get a much better grasp on Objective-C and Xcode.
If you are new to the iPhone/iPad I highly recommend you check out the CS193P lectures, they are also avaliale on itunes. They give a good overview of iPhone programing and how things are done in Objective-C / Cocoa Touch. It will get anyone started in the right direction.
As to your specific question. Just start coding. In 6 months you'll realize eveything you wrote is cr*p and needs to be rewritten anyways, but doing it is the only way you'll realize what you wrote is cr*p so...
Some suggestions, specific to multi-viewed apps (which almost every app is) and I'm sure someone else can expand on this...
Learn (as much as possible) to code interactions between different views and viewcontrollers (vs using interface builder). The twitter app for example doesn't use Interface Builder at all.
If you use IB, don't dump everything into one .xib. Learn how to break them up. One .xib per viewcontroller should be it. I never use the IB UITabBarController or IB UINavigationController, those get initilized and used in code only.
Absolutly learn MVC (Model view controller).
The Apple documentation is often a good place to start for most things. Try here first. Hope this helps and good luck!
I used to use a UINavigationController. I created it as a singleton and accessed it statically so I could push and pop controllers easily (theres a reasonably good tutorial here). This is quite lightweight and theres enough documentation to get going with it quickly.
However the best approach I've used is the Three20 framework's TTNavigator. In a nutshell its a beefed up UINavigator that lets you push a new view onto the screen by calling an internal URL:
//(In your app delegate)
//Start up the navigator
TTNavigator* navigator = [TTNavigator navigator];
navigator.persistenceMode = TTNavigatorPersistenceModeTop;
//Map url's to controllers
TTURLMap* map = navigator.URLMap;
[map from:#"*" toViewController:[TTWebController class]];
[map from:#"ac://search" toViewController:[SearchViewController class]];
[map from:#"ac://results/(initToView:)" toViewController:[ResultsViewController class]];
Then to navigate to a controller:
[[TTNavigator navigator] openURLAction:[[TTURLAction actionWithURLPath:#"ac://results/searchResults/"] applyAnimated:YES]];
Whats also cool is that calling that #"ac://results/" the way we have above passes in the param #"searchResults" to the init method of the ResultsViewController ("initToView:") as we defined in the mapper
All the best!
I have a question regarding nibs and how detail views are created in professional apps. I want to make an app that loads different uitextfields for each nib that is selected from a table. These textfields contain some logic that is different from each. I wanted to ask if it's possible to make one nib and change the data from thatto match all these scenarios. I'm unsure how this is done and how nib management can be done by arrays. Thanks and I hope I was clear enough :)
I can only speak myself but I've moved away from nibs. When you get complex layouts that have elements disappearing and reappearing your nib/s become unmanageable. You can do a better job of keeping elements tidy and manageable in code as well as a slightly faster App (not much but its a nice bonus).
EDIT: As a very basic example just remove any details of a nib and if you class is a UIViewController subclass do this:
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(50,50,150,30);
label.text = #"Hello World";
[self.view addSubview:label];
[label release];
Very basic but hopefully this will get you on your way to developing without nibs. Note: Nibs aren't bad and if its a basic view use them but if you are having complex views you will find nibs becoming unmanageable.
I found this article on Cocoa With Love to be really interesting in regardless to performance of nibs vs code.
IB / Nibs are useful for "getting started" and quick prototyping. However like #Rudiger mentions it's useful only in simple, static layouts. Usually it's only a matter of time before you'll run into limitations and find yourself having to write real code.
So Interface Builder does things to save time but what if I want to do without it ? In C# all code generated is clear and understandable, in interface builder this is hidden so I'd like at least during learning phase do things from scratch: any sample code to do so ?
Seems Apple makes things very hard so as you cannot easily use alternative to Xcode :)
http://cocoawithlove.com/2009/02/interprocess-communication-snooping.html
Yes, you can build a view without IB. Just allocate and initialize a view or a control and set its properties, e.g.:
UITextField *tf= [[UITextField alloc] initWithFrame: CGRectMake(24.5, 65, 270, 30)];
tf.delegate = self;
tf.textAlignment = UITextAlignmentCenter;
tf.autocorrectionType = UITextAutocorrectionTypeNo;
tf.autocapitalizationType = UITextAutocapitalizationTypeNone;
[self.view addSubview: tf];
But IB does not hide any generated code from you because it doesn't generate any code at all. Instead, it creates object instances and serializes them into a XIB or NIB file.
Interface Builder doesn't work in the same way as Visual Studio. It doesn't generate code, instead it generates "raw" object instances. In this sense it's not possible to see the code because there is no code generated.
One option nib2objc to convert your interfaces to code, though I'm not sure how readable that would be. As noted above, this is not the code that would be executed by your iPhone.
This blog post shows you how to get started with a nibless iPhone project.
And you might want to look at this SO question to learn about creating views (e.g. a UIButton in this case) programmatically.
Interface builder doesn't generate code to build a UI object. It creates a compressed xib data object which the iOS runtime "uncompresses" (does some housecleaning) into your pre-built object.
The paradigm is to actually think of you objects as objects in their own right, and not just the results of code execution. e.g. what you would end up with if you could "Make it so." without writing any code.
So I'm trying to use a UITableViewController (let's call it homeView) in my iPhone application to display a simple table with only a few rows of text which are loaded from an NSArray in the controller. I want to display the table in the grouped style in a subview of a subview (let's call it subSubView) of my main controller. When I try the following: [subSubView addSubview:homeView.view], my app crashes on launch. However, when I allocate the object without adding it to any views, it launches fine.
What's the best way (or rather a working way) to display the table generated by my UITableViewController?
There isn't enough to tell for sure what is going on, but if I had to guess I would think that you probably aren't retaining homeView. Normally I would say that as a comment to your question, since it is not really an answer, but I have a completely separate answer:
Just use a UITableView, not a UITableViewController. Instead of trying to embed a controller within a controller (which is quite difficult since Apple doesn't expose the necessary tools to actually modify the view controller hierarchy), just make the VC you are writing support the appropriate delegate/dataSource methods and directly create the view.
While it might make some logical sense to try to embed VCs inside of each other, with the exception of the builtin container VCs (UINavigationController, UITabBarController) it Really Doesn't Workâ˘. The technical reason for this is that internally some of the event routing and messaging depends on parentViewController being correct, but since you can't set it (setParentViewController: is private) tons of latent bugs in UIKit start rearing their head. The internal collection classes can set the parentViewController correctly, so everything works right.
Also, one last thing. In your question you named your view controller homeView. Please, please on't do that. A view controller and a view are separate things, call it homeViewController. Aside from the fact that a lot of new iPhone developers get confused about what the distinction is, there is nothing more aggravating then tracing through someone else's code and realizing that something you are assuming is one type is another.