How to hide share button in QLPreviewController using swift?

问题

I'm using the below code to use QLPreviewcontroller to show some documents in my app,

let ql = QLPreviewController()
ql.dataSource = self
//ql.navigationItem.rightBarButtonItems = nil
ql.navigationItem.rightBarButtonItem = nil
presentViewController(ql, animated: true, completion: nil)

I don't want the share button in the right top of QLPreviewcontroller. I'd tried setting rightBarButtonItem to nil, but it's not working.

How can I hide that?

回答1:

None of those solutions worked for me in Swift 3 for iOS 10. The issue is that the Share button is created after viewDidAppear method.

Here are the steps I followed to remove the share button :

1) Subclassed my QLPreviewController

2) Created a method to open my document in this subclass :

func show(controller: UIViewController, url: NSURL) {
    // Refreshing the view
    self.reloadData()
    // Printing the doc
    if let navController = controller.navigationController {
        navController.pushViewController(self, animated: true)
    }
    else {
        controller.show(self, sender: nil)
    }
}

3) In my viewDidLayoutSubviews, I created a dummy button item to replace the share button :

 override func viewDidLayoutSubviews() {
    navigationItem.rightBarButtonItems?[0] = UIBarButtonItem()
}

4) When I want to open a document in another VC, I call it like this :

 QLSubclass().show(controller: self, url: path as NSURL)

Note : Always call it this way, and not with a global variable you instantiated because you will always see the share button before it disappears.

回答2:

I know this is an old question but I spend so many hours looking for a solution and came up with something that works.

So, for any one looking for the same thing as me. Here's my solution.

Codes are in objective-c but it'l be a simple conversion to Swift

First we create subclass of QLPreviewController and in the subclass override the following methods

Edit

Swift:

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    self.navigationItem.rightBarButtonItem = nil
    //For ipads the share button becomes a rightBarButtonItem
    self.navigationController?.toolbar?.isHidden = true
    //This hides the share item
    self.navigationController?.toolbar?.addObserver(self, forKeyPath: "hidden", options: NSKeyValueObservingOptionPrior, context: nil)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    self.navigationController?.toolbar?.removeObserver(self, forKeyPath: "hidden")
}

override func observeValue(forKeyPath keyPath: String, ofObject object: Any, change: [AnyHashable: Any], context: UnsafeMutableRawPointer) {
    var isToolBarHidden: Bool? = self.navigationController?.toolbar?.isHidden
    // If the ToolBar is not hidden
    if isToolBarHidden == nil {
        DispatchQueue.main.async(execute: {() -> Void in
            self.navigationController?.toolbar?.isHidden = true
        })
    }
}

self.navigationController?.pushViewController(qlPreviewController, animated: true)

Objective-C:

-(void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    self.navigationItem.rightBarButtonItem = nil; //For ipads the share button becomes a rightBarButtonItem
    [[self.navigationController toolbar] setHidden:YES]; //This hides the share item
    [[self.navigationController toolbar] addObserver:self forKeyPath:@"hidden" options:NSKeyValueObservingOptionPrior context:nil];
}

Remove the Observer on viewWillDisappear

-(void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [[self.navigationController toolbar] removeObserver:self forKeyPath:@"hidden"];
}

And the observer method: Required because when you single tap the image to hide the navigation bar and toolbar, the share button becomes visible again on tap.

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{

    BOOL isToolBarHidden = [self.navigationController toolbar].hidden;
    // If the ToolBar is not hidden
    if (!isToolBarHidden) {
        dispatch_async(dispatch_get_main_queue(), ^{
            [[self.navigationController toolbar] setHidden:YES];
        });
    }
}

And the PreviewController has to be pushed from you existing navigationController

[self.navigationController pushViewController:qlPreviewController animated:YES];

And also we have to use the subclass instead of QLPreviewController.

回答3:

If Still, anyone wants to remove share option or want to customize the Navigation bar of QLPreviewController then they can try creating a UIViewController and customize it as per requirement and then create QLPreviewController object and add it as a child view controller.

This will allow you to get rid of share button and you customize navigation bar color etc. this is working for me.

To know, how to add child view controller you can refer to this

回答4:

Create a subclass of QLPreviewController
Add the following code to it

Swift:

var toolbars: [UIView] = []

var observations : [NSKeyValueObservation] = []

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationItem.setRightBarButton(UIBarButtonItem(), animated: false)

    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        navigationController?.toolbar.isHidden = true

        if let navigationToobar = navigationController?.toolbar {
            let observation = navigationToobar.observe(\.isHidden) {[weak self] (changedToolBar, change) in

                if self?.navigationController?.toolbar.isHidden == false {
                     self?.navigationController?.toolbar.isHidden = true
                }
            }
            observations.append(observation)
        }

        toolbars = toolbarsInSubviews(forView: view)

        for toolbar in toolbars {

            toolbar.isHidden = true

            let observation = toolbar.observe(\.isHidden) { (changedToolBar, change) in
                if let isHidden = change.newValue,
                    isHidden == false {
                    changedToolBar.isHidden = true
                }
            }

            observations.append(observation)
        }
    }

    private func toolbarsInSubviews(forView view: UIView) -> [UIView] {

        var toolbars: [UIView] = []

        for subview in view.subviews {
            if subview is UIToolbar {
                toolbars.append(subview)
            }
            toolbars.append(contentsOf: toolbarsInSubviews(forView: subview))
        }
        return toolbars
    }

回答5:

this work for me

   class QLSPreviewController : QLPreviewController {

        override func viewDidLoad() {
            super.viewDidLoad()



        }
        override func viewWillAppear(_ animated: Bool) {
            super.viewWillAppear(animated)

        }
        override func viewDidAppear(_ animated: Bool) {
            super.viewDidAppear(true )
            //This hides the share item
            let add =  self.childViewControllers.first as! UINavigationController
            let layoutContainerView  = add.view.subviews[1] as! UINavigationBar
             layoutContainerView.subviews[2].subviews[1].isHidden = true

        }
    }

来源：https://stackoverflow.com/questions/36256987/how-to-hide-share-button-in-qlpreviewcontroller-using-swift

标签

ios

swift

qlpreviewcontroller

rightbarbuttonitem