Objective-C: Adding UIButtons programmatically from another class - objective-c

Question

I'm having trouble connecting the dots between code and .xib files.
If I want to add a series of UIButtons programmatically to my view controller, how would I go about doing this from a separate class?
For instance, if I have MainViewController.m, which is set as the root view controller in Xcode, how can I add a UIButton to that view controller from SecondViewController.m? Is this even possible?
I would essentially like to place all of my "user interface" code in a separate class.
Thanks

Answer 1

To do this, create a UIButton *myButton programmatically and then call [mainViewController addSubview:myButton];. This may mean you need to store a MainViewController * property in your SecondViewController class.
Important methods and properties for a UIButton instance (essentially, just take a look at the documentation, but here's a minimal set of stuff to get you started):
+[UIButton buttonWithType:buttonType] - Make sure if you're doing anything remotely custom to use UIButtonTypeCustom here (it doesn't give you any default background images or otherwise to have to nil out)
setFrame: - Position the button relative to its container and set the size, for usability reasons the width and height should be at least 44 pixels (as mentioned here).
setTitle:forState: - UIControlStateNormal will act as the default properties for other states too, so you may only need to set the text here
setBackgroundImage:forState: - use UIControlStateNormal and UIControlStateHighlighted/UIControlStateSelected primarily, UIControlStateDisabled if you wish to show it grayed out or inaccessible at any point.
setImage:forState: - Use for an icon next to the button text (like an arrow pointing down for Save or up for Load, etc)
setEnabled:, setHidden:, setSelected: - Transition between different button states. setHighlighted: happens automatically when you tap the button.
addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside - TouchUpInside is almost always what you want for a simple button press, I'm using a method named buttonClicked: here to handle my button press.
Oh, and if you use [[UIButton alloc] initWith...] don't forget to [myButton release] once it's added to the mainViewController :)

Answer 2

use this
#import "MainViewController.h"
#interface SecondViewController
{
MainViewController *mainView;
}
#property(nonatomic, retain) MainViewController *mainView;
-(void)addButtons;
In your implementation
#synthesize mainView;
-(void)addButtons
{
UIButton *add = [UIButton alloc] init];
//do necessary stuff on button here
[self.mainView addSubview:add];
[add release];
}
In your MainViewcontroller.m
#import "SecondViewController.h"
-(void)viewDidLoad
{
[self superViewDidLoad];
SecondViewController *second = [SecondViewController alloc] init];
second.mainView = self;
[second addButton];
[second release];
}