Objective-C：具有拆分视图的UITabBarController

Question

I'm quite new to Objective-C and I'm trying to write my first app for iOS. The idea is quite simple but I have failed already in the beginning architecture construction.

I would like to create different views displayed over several tabs, which should be created dynamically when the view is loaded. Additionally, the app must have the ability to add tabs dynamically at runtime. Tab views should not run over the entire screen but should fill 2/3 of the top view. The remaining 1/3 at the bottom is again divided into two subviews, which are not intended to be changed with tab switches.

What I've done is to create a UIWindow, UITabBarController, and two UIViewControllers (for two tabs) and one (or two as in the figure) which is supposed to be at the bottom.

So far I've managed to switch between different tab views, but as soon as I try to resize UIViewControllers for both tabs with CGMakeRect to any size it always stays the same and covers the entire screen.

The subview created at the bottom contains a button which is somehow not clickable. Maybe because it's covered from the tab views.

Can anyone give me a little help how I can build up those views?

Thanks a lot!

Here is be my code:

self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];


UIViewController *test = [[UIViewController alloc] init];
test.view.backgroundColor = [UIColor grayColor];
test.view.frame = CGRectMake(0, 0, 320, 200);

UIButton *button3 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button3 setTitle:@"View 3" forState:UIControlStateNormal];
button3.frame = CGRectMake(30.0, 30.0, 120.0, 50.0);
[test.view addSubview:button3];


UITabBarController *tabBarController = [[UITabBarController alloc] init];

UIViewController *viewController1 = [[UIViewController alloc] init];
UITabBarItem *tab1 = [[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemBookmarks tag:1];
[viewController1 setTabBarItem:tab1];

UIViewController *viewController2 = [[UIViewController alloc] init];
UITabBarItem *tab2 = [[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemContacts tag:2];
[viewController2 setTabBarItem:tab2];


UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button setTitle:@"View from Tab 1" forState:UIControlStateNormal];
button.frame = CGRectMake(100.0, 100.0, 120.0, 50.0);
[viewController1.view addSubview:button];

UIButton *button2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[button2 setTitle:@"View from Tab 2" forState:UIControlStateNormal];
button2.frame = CGRectMake(100.0, 100.0, 120.0, 50.0);
[viewController2.view addSubview:button2];


tabBarController.viewControllers = [NSArray arrayWithObjects:viewController1, viewController2, nil];

self.window.rootViewController = tabBarController;
[self.window addSubview:test.view];

[self.window makeKeyAndVisible];

Answer 1

Actually there is a way to achieve that thanks to custom container view controllers:

Replace the UITabBarController with a custom subclass of UIViewController as rootViewController of the window. Then in it's viewDidLoad method (or somewhere else depending on your needs) you add almost your exact code from above with some minor modifications. Here's the complete code for the viewDidLoad method (I've added comments above the modified lines):

- (void)viewDidLoad
{
    [super viewDidLoad];


    UITabBarController *tabBarController = [[UITabBarController alloc] init];

    UIViewController *viewController1 = [[UIViewController alloc] init];

    //Mod1: Set an autoresizingMask 
    //so that the view always fills the tabBarController's view
    //if needed you can also set it's frame here
    viewController1.view.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
    UITabBarItem *tab1 = [[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemBookmarks tag:1];
    [viewController1 setTabBarItem:tab1];

    UIViewController *viewController2 = [[UIViewController alloc] init];

    //Mod2: Same here
    viewController2.view.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
    UITabBarItem *tab2 = [[UITabBarItem alloc] initWithTabBarSystemItem:UITabBarSystemItemContacts tag:2];
    [viewController2 setTabBarItem:tab2];


    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button setTitle:@"View from Tab 1" forState:UIControlStateNormal];
    button.frame = CGRectMake(100.0, 100.0, 120.0, 50.0);
    [viewController1.view addSubview:button];

    UIButton *button2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button2 setTitle:@"View from Tab 2" forState:UIControlStateNormal];
    button2.frame = CGRectMake(100.0, 100.0, 120.0, 50.0);
    [viewController2.view addSubview:button2];

    tabBarController.viewControllers = [NSArray arrayWithObjects:viewController1, viewController2, nil];


    //Mod3: Set the frame and autoresizingMask of the tabBarController 
    //to fill the rootVC's view
    tabBarController.view.frame = self.view.bounds;
    tabBarController.view.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;


    //Mod4: This is the important part:
    //add the tabBarController as childVC of the rootVC
    [self addChildViewController:tabBarController];
    [self.view addSubview:tabBarController.view];
    [tabBarController didMoveToParentViewController:self];



    //Mod5: calculate the frame for the 'static' vc on the bottom
    float heightForStaticVC = 200.0f;

    float yPosForStaticVC = tabBarController.view.frame.size.height - tabBarController.tabBar.frame.size.height - heightForStaticVC;


    UIViewController *test = [[UIViewController alloc] init];

    //Mod6: again setting the autoresizingMask
    test.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleTopMargin;
    test.view.backgroundColor = [UIColor grayColor];
    test.view.frame = CGRectMake(0, yPosForStaticVC, 320, heightForStaticVC);

    UIButton *button3 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button3 setTitle:@"View 3" forState:UIControlStateNormal];
    button3.frame = CGRectMake(30.0, 30.0, 120.0, 50.0);
    [test.view addSubview:button3];

    //Mod7: and again adding it as childVC of the rootVC
    [self addChildViewController:test];
    [self.view addSubview:test.view];
    [test didMoveToParentViewController:self];

}

Of course you can modify sizing, positioning and autoresizing behavior as you want.

The result looks like this: