升级到 iOS 11 后弹出错误的位置

Question

自从升级到 iOS 11 后，我开始遇到错误放置的弹出框的问题，它的框架通常由presentPopoverFromRect:sender.frame 设置为导航栏按钮的坐标，从而触发了操作。

问题：(UIButton *)sender.frame 的 x 和 y 坐标等于 {0,0}，并且弹出框显示在屏幕的左上角。

这里是generateToolbar() 方法，它生成用户导航按钮。

-(void) generateToolbar {

    // Initialize the `ButtonFactory`

    ButtonFactory *buttonFactory = [[ButtonFactory alloc] init];

    // Generate some UIButton(s)

    UIButton *userUIBtn = [buttonFactory createButtonWithButtonType:ButtonTypeUser iconVisibility:YES textVisibility:NO capitalization:NO iconSize:20 textSize:10];
    userUIBtn.frame = CGRectMake(0,0,55,20);
    [userUIBtn addTarget:self action:@selector(userButtonPressed:) forControlEvents:UIControlEventTouchUpInside];

    // Generate an `UIBarButtonItem` with the `UIButton` as basis

    UIBarButtonItem *userBtn = [[UIBarButtonItem alloc] initWithCustomView:userUIBtn];

    // Add the `UIBarButtonItem` into the right side of the `navigationItem`

    self.navigationItem.rightBarButtonItems = [[NSArray alloc] initWithObjects: userBtn, nil];

    DDLogVerbose(@"A: generateToolbar UIButton FRAME: %@",NSStringFromCGRect(userUIBtn.frame));

}

这里是 userButtonPressed() 方法，它通过按下 user 按钮触发并在该按钮周围生成一个弹出框。

- (IBAction) userButtonPressed:(UIButton *)sender {

    // Initialize the `ButtonFactory`

    ButtonFactory *buttonFactory = [[ButtonFactory alloc] init];

    // Generate some UIButtons        

    UIButton *feedbackUIBtn = [buttonFactory createButtonWithButtonType:ButtonTypeFeedback iconVisibility:YES textVisibility:YES capitalization:NO iconSize:20.0 textSize:20.0];
    [feedbackUIBtn addTarget:self action:@selector(feedbackBtnClicked:) forControlEvents:UIControlEventTouchUpInside];
    feedbackUIBtn.frame = CGRectMake(0,50,300,50);

    // Create a `UIViewController` and add the `UIButtons` as subviews

    UIViewController *viewController = [[UIViewController alloc] init];
    [viewController.view addSubview:feedbackUIBtn];
    [viewController.view addSubview:crashUIBtn];

    // Create the `UIPopoverController`

    UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
    self.mainPopoverController = [[UIPopoverController alloc] initWithContentViewController:navigationController];
    self.mainPopoverController.popoverContentSize = CGSizeMake(300, 100); 

    DDLogVerbose(@"B: userButtonPressed SENDER FRAME: %@",NSStringFromCGRect(sender.frame));

    // Present the `UIPopoverController`

    [self.mainPopoverController presentPopoverFromRect:sender.frame inView:self.view permittedArrowDirections: UIPopoverArrowDirectionLeft | UIPopoverArrowDirectionUp animated:YES];
}

日志输出——两处x、y坐标都等于{0, 0}，这是错误的，它们应该是非零且等于UIBarButtonItem的实际坐标：

A: generateToolbar UIButton FRAME: {{0, 0}, {55, 20}}
B: userButtonPressed SENDER FRAME: {{0, 0}, {55, 32}}

Answer 1

“导航栏按钮坐标”的概念没有意义，因为 UIBarButtonItem 不是 UIView 并且没有 frame。将弹出箭头指向 UIBarButtonItem 的方法是设置弹出显示控制器的barButtonItem。 （popover presentation 控制器：在这个时代你不应该使用 UIPopoverController。）