Question

我正在尝试找到一种干净的方式来处理UIPageViewController和状态栏。我注意到Snapchat在滑动到没有显示状态栏的新页面时，通过在状态栏上滑动viewcontroller来完美地完成它。它看起来像这样......

snapchat statusbar uipageviewcontroller http://i62.tinypic.com/htcrj5.png

有谁知道这是怎么做的？我能想到的唯一方法是使用不同的UIWindow，但是如何实现具有多个UIWindows的UIPageViewController？如果这就是正在做的事情。否则如何实现这种效果？

Answer 1

基本上创建一个UIViewController，把UIPageViewController放在里面。使UIVC的大小与iphone屏幕的大小相同。然后将appdelegate.window.rootviewcontroller设置为UIViewControllers

以下是此任务的一个很好的示例回购：https://github.com/goktugyil/EZSwipeController

Answer 2

好的，所以这实际上是使用一些聪明的技巧完成的。

基本上它并没有实际移动状态栏，而是移动状态栏的图像。

免责声明：我执行此实施工具，因此我不保证它是否可以开箱即用

从iOS7开始，您可以使用

拍摄照片

UIView *screen = [[UIScreen mainScreen] snapshotViewAfterScreenUpdates:NO];

我看到here提供了更多有用的信息。但基本上状态栏会从图片中裁剪下来，并添加到UIWindow windowLevel以上UIWindowStatusLevelBar，这将掩盖真实的状态栏。类似的东西：

UIWindow *statusBarWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
statusBarWindow.windowLevel = UIWindowLevelStatusBar;
statusBarWindow.hidden = NO; // fun fact you don't have to add a UIWindow to anything, just setting hidden = NO should display it
statusBarWindow.backgroundColor = [UIColor clearColor]; // I have no idea if this is necessary but since it's now visible you def don't want it to have a color

...

// The view that will hold the screen shot
UIView *statusBarView = [[UIView alloc] initWithFrame:[UIApplication sharedApplication].statusBarFrame];
statusBarView.clipsToBounds = YES;

// Now we add the screen shot we took to this status bar view
[statusBarView addSubview:screen]; // screen is the UIView from previous code block

// Now add this statusBarView with the image to the window we created
[statusBarWindow addSubview:statusBarView];

现在其余部分真的取决于你的实现是什么样的，但是从这里你真的只需要处理移动视图的平移，或任何导致新视图进入侧面的动作：

// you're going to want to hide the status bar when this action starts so that your new window is visible
[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationNone];

// then inside whatever method is handling the sliding you're going to adjust the frame of the statusBarView
// this can be done explicitly by setting a new frame, or animating its x position, or whatever

// if you're doing it explicitly something like:
CGFloat offset = self.viewThatIsScrolling.contentOffset.x; // may be negative depending on direction that is being swiped
statusBarView.frame = CGRectMake(offset, 0, self.statusBarView.frame.width, 20.0f);
// or maybe even
statusBarView.transform = CGAffineTransformMakeTranslation(offset -previousOffsetAmount, 0); // you only want it to move over by whatever new amount so it can match up, this will have to be tracked somehow if you go this route

... 

// and finally once the 'sliding' is done don't forget to remove the screenshot and unhide the status bar
// (can check by looking at the offset value from earlier or as a callback after animation, or whatever)
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationNone];
[statusBarView removeFromSuperview];
statusBarView = nil;

另请注意，这不会处理方向更改或任何内容（固定框架可能导致其无法工作）。你可以使用autoResizingMask或其他东西

在状态栏上滑动UIPageViewController页面

2 个答案: