iPhone上的UIPopoverPresentationController不会产生弹出窗口

Question

我正在尝试在我的iPhone应用程序中实现新的UIPopoverPresentationController（使用Objective C）。我想要的是一个简单的popover，其中包含一个从启动按钮发出的tableview。

- 编辑 -

以下是我的修改代码，改编自文档中的研究，SO以及以下评论中的输入：

- (IBAction)selectCategoryBtn:(UIButton *)sender
{
    [self performSegueWithIdentifier:@"CatSelectSegue" sender:self.selCatButton];
}

-(void) prepareForSegue:(UIStoryboardSegue *) segue Sender:(id) sender
{
    if (sender == self.selCatButton)
    {
        if ([segue.identifier isEqualToString:@"CatSelectSegue"])
        {
            UIPopoverPresentationController *controller = segue.destinationViewController;
            controller.delegate = self;
            controller.sourceView = self.selCatButton;
            controller.sourceRect = self.selCatButton.frame;
        }
    }
}


-(UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller
{
    return UIModalPresentationNone;

这是我的故事板连接：

然而，这只是以模态方式呈现一个桌面视图，从底部上升并消耗整个屏幕。

我已经用Google搜索了，并且看起来都是如此，但看起来我并不是唯一一个被我希望解决iPhone烦恼问题所迷惑的人。

任何人都可以在我的代码中看到一个小故障或指导我一个明确的教程吗？我看过了，但也许API是如此新的没有人能够处理它。

谢谢！

第二次修改：

以下是上述代码的结果。我减少了视图控制器中的tableview的大小，我希望将其作为弹出窗口呈现。我把背景涂成灰色，只是为了澄清出现的是什么而不是弹出窗口。

Answer 1

步骤：

A）使用UIButton segue类型将Present As Popover链接到popover的视图控制器。我实际上必须创建一个新项目才能显示它，但它可能与基本SDK有关。

B）使包含UIButton的视图控制器符合<UIPopoverPresentationControllerDelegate>。例如。在MyViewController.m文件中添加：

@interface MyViewController () <UIPopoverPresentationControllerDelegate>

C）将以下方法添加到包含UIButton：

的View Controller中

- (UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller {

    return UIModalPresentationNone;
}

D）将以下内容添加到prepareForSegue:sender:替换segue.identifier支票：

中

if ([segue.identifier isEqualToString:@"CatSelectSegue"]) {
    UIViewController *dvc = segue.destinationViewController;
    UIPopoverPresentationController *controller = dvc.popoverPresentationController;
    if (controller) {
        controller.delegate = self;
    }
}

代码测试并证明其有效：

编辑：我的测试应用程序TPOPViewController.m文件，其中发生了魔术：

#import "TPOPViewController.h"

@interface TPOPViewController () <UIPopoverPresentationControllerDelegate>//, UIAdaptivePresentationControllerDelegate>

@end

@implementation TPOPViewController

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    NSString *identifier = segue.identifier;
    if ([identifier isEqualToString:@"popover"]) {
        UIViewController *dvc = segue.destinationViewController;
        UIPopoverPresentationController *ppc = dvc.popoverPresentationController;
        if (ppc) {
            if ([sender isKindOfClass:[UIButton class]]) { // Assumes the popover is being triggered by a UIButton
                ppc.sourceView = (UIButton *)sender;
                ppc.sourceRect = [(UIButton *)sender bounds];
            }
            ppc.delegate = self;
        }
    }
}

- (UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller {

    return UIModalPresentationNone;
}

@end

我的测试故事板：

Answer 2

显然上述方法不再适用于 iOS9 / Xcode7 。这是因为如果你将segue样式设置为＆＃34; Popover＆＃34;使用Interface Builder，Xcode在编译应用程序时会忽略它。此外，它会自动将segue设置回＆＃34; Push＆＃34;下次打开项目时。如果您有像Git这样的版本控制软件，那么您将能够观察到这种不必要的变化。

然而，如果您手动呈现您想要显示为弹出窗口的视图控制器，它仍然可以在iPhone上获得iPad样式的弹出式窗口。示例Swift代码：

//  ViewController.swift
//  PopoverDemo
//
//  Created by bhnascar on 12/2/15.
//  Copyright © 2015 bhnascar. All rights reserved.
//

import UIKit

class ViewController: UIViewController, UIPopoverPresentationControllerDelegate {

    /* The bar button item that will present the popover. */
    var popoverButton: UIBarButtonItem?

    override func viewDidLoad() {
        super.viewDidLoad()
        popoverButton = UIBarButtonItem(title: "Pop!", style: UIBarButtonItemStyle.Plain, target: self, action: "presentPopover")
        self.navigationItem.rightBarButtonItem = popoverButton
    }

    // Mark: - UIPopoverPresentationControllerDelegate

    func prepareForPopoverPresentation(popoverPresentationController: UIPopoverPresentationController) {
        popoverPresentationController.permittedArrowDirections = .any
        popoverPresentationController.barButtonItem = popoverButton
    }

    func adaptivePresentationStyle(for controller: UIPresentationController) -> UIModalPresentationStyle {
        return .none
    }

    // Mark: - Callback function for popover button.

    func presentPopover() {
        let popoverContentController = UIViewController()
        popoverContentController.view.backgroundColor = .blue

        // Set your popover size.
        popoverContentController.preferredContentSize = CGSize(width: 300, height: 300)

        // Set the presentation style to modal so that the above methods get called.
        popoverContentController.modalPresentationStyle = .popover

        // Set the popover presentation controller delegate so that the above methods get called.
        popoverContentController.popoverPresentationController!.delegate = self

        // Present the popover.
        self.present(popoverContentController, animated: true, completion: nil)
    }

}

Answer 3

SWIFT 3.X

这将在屏幕中央显示弹出窗口

class CommonViewController: UIViewController, UIPopoverPresentationControllerDelegate{

func adaptivePresentationStyle(
for controller: UIPresentationController,
    traitCollection: UITraitCollection)
    -> UIModalPresentationStyle {
        return .none
}

func showPopover(){
    let storyboard = UIStoryboard(name: "Pickers", bundle: nil)
    let myViewController = UIViewController()
    myViewController.preferredContentSize = CGSize(width: 320, height: 200)
    myViewController.modalPresentationStyle = .popover

    let popOver = myViewController.popoverPresentationController
    popOver?.delegate = self

    self.present(myViewController, animated: true, completion: nil)
    popOver?.permittedArrowDirections = .init(rawValue: 0)
    popOver?.sourceView = self.view

    let rect = CGRect(
        origin: CGPoint(x: self.view.frame.width/2, y: self.view.frame.height/2),
        size: CGSize(width: 1, height: 1)
    )
    popOver?.sourceRect = rect
}

Answer 4

从iPhone / iPad呈现UIModalPresentationStyle popover：

-(void)menuButtonPressed:(UIButton *)sender {

    self.menuPopoverController = [[DownloadMenuPopoverController alloc] initWithStyle:UITableViewStylePlain];
    self.menuPopoverController.delegate = self;

    self.menuPopoverController.modalPresentationStyle = UIModalPresentationPopover;
    self.menuPopoverController.popoverPresentationController.delegate = self;
    self.menuPopoverController.preferredContentSize = CGSizeMake(250,80);
    self.menuPopoverController.popoverPresentationController.sourceRect = sender.frame;// rect to show view
    self.menuPopoverController.popoverPresentationController.sourceView = self.view;

    UIPopoverPresentationController *popPC = self.menuPopoverController.popoverPresentationController;
    popPC.permittedArrowDirections = UIPopoverArrowDirectionAny;
    popPC.delegate = self;
    [self presentViewController:self.menuPopoverController animated:YES completion:nil];

}

#pragma mark - UIPresentationController Delegate methods

- (UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller traitCollection:(UITraitCollection *)traitCollection {
    return UIModalPresentationNone;
}

- (UIViewController *)presentationController:(UIPresentationController *)controller viewControllerForAdaptivePresentationStyle:(UIModalPresentationStyle)style {
    UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:controller.presentedViewController];
    return navController;
}