UINavigationController里面的UITabBarController里面的UITableViewController

Question

My Problem

I am using a UITabBarController inside a UINavigationController. And there are three tableviews inside the UITabBarController. As shown in the picture, the first table view shows correctly while the other two tableviews are partially hidden behind the navigation bar. How can I fix this?

My hierarchy:

• Root: UINavigationController
  • UITabBarController
    • UITableViewController (table1,table2,table3)

Here is my code:

AppDelegate.m

#import "AppDelegate.h"
#import "TableViewController.h"
@interface AppDelegate()
@property UINavigationController* nav;
@end

@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    TableViewController* table1 = [[TableViewController alloc]init];
    TableViewController* table2 = [[TableViewController alloc]init];
    TableViewController* table3 = [[TableViewController alloc]init];
    table1.title = @"table1";
    table2.title = @"table2";
    table3.title = @"table3";
    UITabBarController* t = [[UITabBarController alloc] init];
    [t setViewControllers:@[table1,table2,table3]];
    self.nav = [[UINavigationController alloc] initWithRootViewController:t];
    [self.window setRootViewController:self.nav];
    [self.window makeKeyAndVisible];
    return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application{}
- (void)applicationDidEnterBackground:(UIApplication *)application{}
- (void)applicationWillEnterForeground:(UIApplication *)application{}
- (void)applicationDidBecomeActive:(UIApplication *)application{}
- (void)applicationWillTerminate:(UIApplication *)application{}
@end

TableViewController.m

#import "TableViewController.h"
@implementation TableViewController
- (id)initWithStyle:(UITableViewStyle)style{
    self = [super initWithStyle:style];
    if (self) {}
    return self;
}
- (void)viewDidLoad{
    [super viewDidLoad];
    [self.tabBarController.view layoutSubviews];
}
- (void)didReceiveMemoryWarning{
    [super didReceiveMemoryWarning];
}
#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
    return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    return 10;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    UITableViewCell* c = [[UITableViewCell alloc] init];
    [c.textLabel setText:[NSString stringWithFormat:@"%d", indexPath.row]];
    return c;
}
@end

Answer 1

Typically, the hierarchy is

UITabBarController
    - UINavigationController
        - UITableViewController

Why are you trying to put the Navigation Controller on top? Try reorganizing using a tab bar full of navigation controllers instead.

Answer 2

I hit this same problem yesterday, and decided to work around it. It's just one class that gets in the way, so here's the rewrite:

DRTabBarController.h

//
// Created by Dan Rosenstark on 2/28/15.
// Copyright (c) 2015 Confusion Studios LLC. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface DRTabBarController : UIViewController <UITabBarDelegate>;

@property (nonatomic, strong) NSArray *viewControllers;
@property (nonatomic, strong) UITabBar *tabBar;
@property (nonatomic, strong) UIView *mainView;

@end

DRTabBarController.m

//
// Created by dr2050 on 2/28/15.
// Copyright (c) 2015 Confusion Studios LLC. All rights reserved.
//

#import "DRTabBarController.h"


@implementation DRTabBarController {


}


- (instancetype)init {
    self = [super init];
    if (self) {
        self.tabBar = [[UITabBar alloc] init];
        self.tabBar.delegate = self;
        self.tabBar.tintColor = [UIColor whiteColor];
        self.tabBar.barStyle = UIBarStyleBlack;
        self.tabBar.backgroundColor = [UIColor blackColor];

        self.mainView = [[UIView alloc] init];
    }
    return self;
}

- (void)viewDidLoad {
    [self.view addSubview:self.tabBar];
    [self.view addSubview:self.mainView];
}

- (void)setViewControllers:(NSArray *)viewControllers {
    _viewControllers = viewControllers;

    NSMutableArray *tabBarItems = [NSMutableArray array];
    for (UIViewController *controller in viewControllers) {
        UITabBarItem *item = controller.tabBarItem;
        [tabBarItems addObject:item];
    }
    self.tabBar.items = tabBarItems;
}


- (void)viewWillAppear:(BOOL)animated {
    [self.tabBar setSelectedItem:self.tabBar.items.firstObject];
    [self tabBar:self.tabBar didSelectItem:self.tabBar.items.firstObject];
}

- (void)viewDidAppear:(BOOL)animated {



}

-(void)viewDidLayoutSubviews {
    CGRect frame = self.view.bounds;
    UITabBarController *throwaway = [[UITabBarController alloc] init];
    frame.size.height = throwaway.tabBar.frame.size.height;
    frame.origin.y = self.view.bounds.size.height - frame.size.height;
    self.tabBar.frame = frame;
    self.tabBar.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin;

    frame = self.view.bounds;
    frame.size.height -= self.tabBar.frame.size.height;

    float navbarHeight = self.navigationController.navigationBar.frame.size.height;
    // cannot use UIApplication.sharedApplication.statusBarFrame.size.height because
    // reports are not right with in-call status bar
    float statusBarHeight = UIApplication.sharedApplication.statusBarHidden ? 0 : 20;
    float topBarHeight = navbarHeight + statusBarHeight;

    frame.origin.y += topBarHeight;
    frame.size.height -= topBarHeight;
    self.mainView.frame = frame;
    self.mainView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
}

- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item {
    int index = [self.tabBar.items indexOfObject:item];
    NSArray *subviews = self.mainView.subviews;
    for (UIView *view in subviews) {
        [view removeFromSuperview];
    }
    UIView *view = [[self.viewControllers objectAtIndex:index] view];
    view.frame = self.mainView.bounds;
    view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    [self.mainView addSubview:view];
}


@end

Note: There's one magic variable in there -- 20 -- for the in-call status bar, which has a totally different relationship to the surrounding nav...

Any help with this would be appreciated, but does work.