Open UISplitViewController to Master View rather than Detail

Question

I have a split-view interface with a target iPhone 6 application. On the first launch of the application, it opens to the Detail View; I would like it to open to the Master View. I have tried:

self.splitViewController?.preferredDisplayMode = UISplitViewControllerDisplayMode.PrimaryOverlay

Which was suggested elsewhere (Prior StackOverFlow Question) but it doesn't seem to do anything, and does not open the Master view on launch. I also tried to add the following line to my AppDelegate:

splitViewController:collapseSecondaryViewController:ontoPrimaryViewController:

But despite returning true or false (Another Prior Stack Overflow Question) I had no success.

I did launch up the example Master-Detail application in Xcode, and it loads to the Master view based on the splitViewController: call returning false; however, I'm not sure how to make this work in a more complicated layout.

Answer 1

Swift

UISplitViewController display master view above detail in portrait orientation is not about showing the Master view, it is about presenting the Detail view in full width, underneath the Master view.

UISplitViewController in portrait on iPhone shows detail VC instead of master is about the principle of the collapse mechanism.

This present answer addresses:

• Master → Detail (Compact width)
  • iPhone 4s, 5, 5s, SE, 6, 6s, 7 (any orientation)
  • iPod Touch
  • any iPhone Plus (portrait)
• side-by-side (all other sizes)
  • iPad
  • any iPhone Plus (landscape)

You must set preferredDisplayMode. You would want is .primaryVisible if it existed! Using .allVisible, iOS picks Detail if only 1 view fits (Compact width); in that size, the code below will pick Master.

The trick is to change both the preferredDisplayMode to .allVisible and to return true in collapseSecondary:onto.

class PrimarySplitViewController: UISplitViewController,
                                  UISplitViewControllerDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()
        self.delegate = self
        self.preferredDisplayMode = .allVisible
    }

    func splitViewController(
             _ splitViewController: UISplitViewController,
             collapseSecondary secondaryViewController: UIViewController,
             onto primaryViewController: UIViewController) -> Bool {
        // Return true to prevent UIKit from applying its default behavior
        return true 
    }
}

Answer 2

Step 1 - Open MasterViewController

Step 2 - ensure the table view has the UISplitViewControllerDelegate protocol. Eg:

class ListVC: UITableViewController,UISplitViewControllerDelegate {}

Step 3 - Add it in ViewDidLoad

splitViewController?.delegate = self

Step 4 - Then override this method to say the master view controller should always collapse onto the detail view controller:

func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController: UIViewController, onto primaryViewController: UIViewController) -> Bool {
    return true
}

Answer 3

iOS 14

I wasn't getting a callback for splitViewController(_:collapseSecondary:onto:) and instead used the following new method.

func splitViewController(_ svc: UISplitViewController, topColumnForCollapsingToProposedTopColumn proposedTopColumn: UISplitViewController.Column) -> UISplitViewController.Column {
    return .primary
}

Answer 4

On the first launch of the application, it opens to the Detail View; I would like it to open to the Master View

Assuming you want that only on the first launch, but not always; for example in the case that the Master View shows an empty data set; then the solution is just as the Master-Detail template shows:

func splitViewController(splitViewController: UISplitViewController, collapseSecondaryViewController secondaryViewController:UIViewController, ontoPrimaryViewController primaryViewController:UIViewController) -> Bool {
    guard let secondaryAsNavController = secondaryViewController as? UINavigationController else { return false }
    guard let topAsDetailController = secondaryAsNavController.topViewController as? DetailViewController else { return false }
    if topAsDetailController.detailItem == nil {
        // Return true to indicate that we have handled the collapse by doing nothing; the secondary controller will be discarded.
        return true
    }
    return false
}

Answer 5

iOS 14

From WWDC 2020 - Build for iPad, You can add a specific view controller for the compact width class (e.g. iPhone in portrait, iPad in Slide Over) by checking Use Separate View Controller in the Attribute Inspector of SplitViewController.

So you can set any view controller as an initial view controller as you want by setting relationship segue.

Answer 6

Or just inherit from UISplitViewController and use this new class in the storyboard (based on SwiftArchitect's answer):

class MasterShowingSplitViewController :UISplitViewController, UISplitViewControllerDelegate {
    override func viewDidLoad() {
        super.viewDidLoad()

        self.delegate = self
        self.preferredDisplayMode = .allVisible
    }

    func splitViewController(
        _ splitViewController: UISplitViewController,
        collapseSecondary secondaryViewController: UIViewController,
        onto primaryViewController: UIViewController) -> Bool {
        // Return true to prevent UIKit from applying its default behavior
        return true
    }
}

Answer 7

This is an oldish question and none of the answers were for Objective C, and even when I ported the Swift answers, none worked for me. One was close, by @SwiftArchitect.

But he recommended setting the content mode to .allVisible (UISplitViewControllerDisplayModeAllVisible in Objective C) - this makes the master view display all the time, splitting the view into master on one side, detail on the other. Which is kinda cool, but the OP asked specifically to display the master view on initial launch, which is what I needed to do.

The change was to use UISplitViewControllerDisplayModePrimaryOverlay for the display mode.

This answer is for Xcode 9.4.1, deployment target 11.4.

Here is MasterViewController.h - you need to add UISplitViewControllerDelegate in the protocols declaration:

#import <UIKit/UIKit.h>
#import <CoreData/CoreData.h>
#import "MasterDetailDemo+CoreDataModel.h"

@class DetailViewController;

@interface MasterViewController : UITableViewController
<UISplitViewControllerDelegate,
NSFetchedResultsControllerDelegate>

@property (strong, nonatomic) DetailViewController *detailViewController;

@property (strong, nonatomic) NSFetchedResultsController<Event *> *fetchedResultsController;
@property (strong, nonatomic) NSManagedObjectContext *managedObjectContext;

@end

And then in your MasterViewController.m, you need to set the split view controller delegate and the content mode in ViewDidLoad, and following along with @SwiftArchitect's answer, to also add the split view controller delegate method:

- (void)viewDidLoad {

    [super viewDidLoad];

    // needed to "slide out" MasterView on startup on iPad
    self.splitViewController.delegate = self;
    self.splitViewController.preferredDisplayMode = UISplitViewControllerDisplayModePrimaryOverlay;

    self.navigationItem.leftBarButtonItem = self.editButtonItem;

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

    self.navigationItem.rightBarButtonItem = addButton;

    self.detailViewController = (DetailViewController *)[[self.splitViewController.viewControllers lastObject] topViewController];
}

// split view delegate method
- (BOOL)splitViewController:(UISplitViewController *)splitViewController collapseSecondaryViewController:(UIViewController *)secondaryViewController ontoPrimaryViewController:(UIViewController *)primaryViewController {
    return true;
}

NOTE: After some testing, I found that the split view delegate method and the split view protocol was not necessary. Without it, it appears to work exactly the same. Perhaps this is a result of changes in iOS since the question was originally asked and answered.

I got it working fine just by putting this line in my ViewDidLoad method:

self.splitViewController.preferredDisplayMode = UISplitViewControllerDisplayModePrimaryOverlay;

Answer 8

iOS 14 -- Two Column Mode Updates

I struggled with this for a while before eventually finding that the Split View Controller has been reworked in iOS14, so none of the answers above are relevant anymore.

I'd recommend starting with this article here.

But in case you are looking for a quick fix:

• You'll need to set the "compact view controller" relationship on your Split View Controller. You can do this by right-clicking the Split View Controller and dragging a new relationship to the view controller you would like to display in compact mode.
• My app has a TableView, and in compact mode I want to push a Detail View Controller when a cell is tapped. In the new iOS 14 SplitView Controller, this has to be done manually. I did this by adding the following to my didSelectRowAt function:

        // If we are in compact mode, we need to push the detail view controller
        if let splitViewController = splitViewController {
            if splitViewController.isCollapsed {
                let shipmentDetailViewController = storyboard?.instantiateViewController(identifier: "shipmentDetailViewController") as! ShipmentDetailViewController
                shipmentDetailViewController.shipment = selectedShipment
                self.navigationController?.pushViewController(shipmentDetailViewController, animated: true)
            }
        }

Answer 9

Swift 5, iOS 13

I found other answers useful, but not-quite-there in that they produced the behavior I wanted on iPad or iPhone, but not both.

The solution below is what I used for:

iPhone: Master view always appears first

iPad Portrait: detail always appears, but with master overlaying it; detail is full-screen (not just right-of-master)

iPad Landscape: Master always on left, detail always on right

class RootSplitViewController: UISplitViewController {
    override func viewDidLoad() {
        if UIDevice.current.userInterfaceIdiom == .pad {
            self.preferredDisplayMode = .automatic
        }
        else {
            self.preferredDisplayMode = .allVisible
        }
        self.delegate = self
    }
}

extension RootSplitViewController: UISplitViewControllerDelegate {
    func splitViewController(_ splitViewController: UISplitViewController,
                             collapseSecondary secondaryViewController:UIViewController,
                             onto primaryViewController:UIViewController)
        -> Bool
    {
        if AppState.instance.currentSelectedEvent == nil {
            // Return true to indicate that we have handled the collapse by doing nothing; the secondary controller will be discarded.
            return true
        }
        else {
            return false
        }
    }
}