分割视图的使用

分割视图是 iPad 的特定视图控制器用于管理两个视图控制器,在左侧是一个主控制器,其右侧是一个详细信息视图控制器。 重要的属性

  • delegate
  • viewControllers

示例代码和步骤

1.创建一个新项目,选择Master Detail Application并单击下一步,输入项目名称,然后选择创建。

2.简单的分割视图控制器与母版中的表视图是默认创建的。

3.在这里我们为我们创建的下列文件。

  • AppDelegate.h
  • AppDelegate.m
  • DetailViewController.h
  • DetailViewController.m
  • DetailViewController.xib
  • MasterViewController.h
  • MasterViewController.m
  • MasterViewController.xib

4. AppDelegate.h文件如下所示

#import <UIKit/UIKit.h>

@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;

@property (strong, nonatomic) UISplitViewController *splitViewController;

@end

5.在AppDelegate.m中的didFinishLaunchingWithOptions方法,如下所示

 - (BOOL)application:(UIApplication *)application 
   didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
   self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen]
   bounds]];
    // Override point for customization after application launch.
    MasterViewController *masterViewController = [[MasterViewController
    alloc] initWithNibName:@"MasterViewController" bundle:nil];
    UINavigationController *masterNavigationController = 
    [[UINavigationController alloc] initWithRootViewController:
    masterViewController];

    DetailViewController *detailViewController = 
    [[DetailViewController alloc] initWithNibName:@"DetailViewController" 
    bundle:nil];
    UINavigationController *detailNavigationController = 
    [[UINavigationController alloc] initWithRootViewController:
    detailViewController];

    masterViewController.detailViewController = detailViewController;

    self.splitViewController = [[UISplitViewController alloc] init];
    self.splitViewController.delegate = detailViewController;
    self.splitViewController.viewControllers =
    @[masterNavigationController, detailNavigationController];
    self.window.rootViewController = self.splitViewController;
    [self.window makeKeyAndVisible];
    return YES;
}

6. MasterViewController.h,如下所示

#import <UIKit/UIKit.h>

@class DetailViewController;

@interface MasterViewController : UITableViewController

@property (strong, nonatomic) DetailViewController *detailViewController;

@end

7. MasterViewController.m,如下所示

#import "MasterViewController.h"

#import "DetailViewController.h"

@interface MasterViewController () {
    NSMutableArray *_objects;
}
@end

@implementation MasterViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)
  nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        self.title = NSLocalizedString(@"Master", @"Master");
        self.clearsSelectionOnViewWillAppear = NO;
        self.contentSizeForViewInPopover = CGSizeMake(320.0, 600.0);
    }
    return self;
}
                            
- (void)viewDidLoad
{
    [super viewDidLoad];
    self.navigationItem.leftBarButtonItem = self.editButtonItem;

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] 
    initWithBarButtonSystemItem: UIBarButtonSystemItemAdd 
    target:self action:@selector(insertNewObject:)];
    self.navigationItem.rightBarButtonItem = addButton;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)insertNewObject:(id)sender
{
    if (!_objects) {
        _objects = [[NSMutableArray alloc] init];
    }
    [_objects insertObject:[NSDate date] atIndex:0];
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
    [self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:
    UITableViewRowAnimationAutomatic];
}

#pragma mark - Table View

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

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:
  (NSInteger)section
{
    return _objects.count;
}

// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
  (NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:
    CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:
        UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }


    NSDate *object = _objects[indexPath.row];
    cell.textLabel.text = [object description];
    return cell;
}

- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:
  (NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}

- (void)tableView:(UITableView *)tableView commitEditingStyle:
  (UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:
  (NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        [_objects removeObjectAtIndex:indexPath.row];
        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:
        UITableViewRowAnimationFade];
    } else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into 
        //the array, and add a new row to the table view.
    }
}

/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:
  (NSIndexPath *) fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/

/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:
  (NSIndexPath *)indexPath
{
    // Return NO if you do not want the item to be re-orderable.
    return YES;
}
*/

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:
  (NSIndexPath *)indexPath
{
    NSDate *object = _objects[indexPath.row];
    self.detailViewController.detailItem = object;
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat: @"yyyy-MM-dd HH:mm:ss zzz"];  
    NSString *stringFromDate = [formatter stringFromDate:object];
    self.detailViewController.detailDescriptionLabel.text = stringFromDate;
}

@end

8. DetailViewController.h ,如下所示

#import <UIKit/UIKit.h>

@interface DetailViewController : UIViewController
<UISplitViewControllerDelegate>

@property (strong, nonatomic) id detailItem;

@property (weak, nonatomic) IBOutlet UILabel *detailDescriptionLabel;
@end

9. DetailViewController.m ,如下所示

#import "DetailViewController.h"

@interface DetailViewController ()
@property (strong, nonatomic) UIPopoverController *masterPopoverController;
- (void)configureView;
@end

@implementation DetailViewController

#pragma mark - Managing the detail item

- (void)setDetailItem:(id)newDetailItem
{
    if (_detailItem != newDetailItem) {
        _detailItem = newDetailItem;
        
        // Update the view.
        [self configureView];
    }

    if (self.masterPopoverController != nil) {
        [self.masterPopoverController dismissPopoverAnimated:YES];
    }        
}

- (void)configureView
{
    // Update the user interface for the detail item.

    if (self.detailItem) {
        self.detailDescriptionLabel.text = [self.detailItem description];
    }
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self configureView];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:
  (NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        self.title = NSLocalizedString(@"Detail", @"Detail");
    }
    return self;
}
                            
#pragma mark - Split view

- (void)splitViewController:(UISplitViewController *)splitController 
  willHideViewController:(UIViewController *)viewController withBarButtonItem:
  (UIBarButtonItem *)barButtonItem forPopoverController:
  (UIPopoverController *)popoverController
{
    barButtonItem.title = NSLocalizedString(@"Master", @"Master");
    [self.navigationItem setLeftBarButtonItem:barButtonItem animated:YES];
    self.masterPopoverController = popoverController;
}

- (void)splitViewController:(UISplitViewController *)splitController 
  willShowViewController:(UIViewController *)viewController 
  invalidatingBarButtonItem:(UIBarButtonItem *)barButtonItem
{
    // Called when the view is shown again in the split view, 
    //invalidating the button and popover controller.
    [self.navigationItem setLeftBarButtonItem:nil animated:YES];
    self.masterPopoverController = nil;
}

@end

10.现在当我们运行应用程序时,在横向模式下我们会得到下面的输出

masterDetailOutput1

11. 当我们切换到纵向模式,我们会获得下面的输出:

masterDetailOutput2