iPad显示肖像，但认为它是风景 [英] iPad shows at portrait but thinks it's landscape

问题描述

我的Storybuilder设计为纵向布局.当我将iPad转到水平位置时启动该应用程序时，它可以正确检测到它处于水平位置.但是，当我将iPad纵向放置时启动该应用程序时，它会认为它是水平的.但是，每次旋转时，代码都能够正确检测到正确的方向.

My Storybuilder is designed with a portrait layout. When I start the app with my iPad already turned to horizontal, it's able to correctly detect it's in a horizontal position. But when I start the app with my iPad in a portrait position, it thinks it's in horizontal. However, every time I rotate it, the code is able to detect the correct orientation properly.

- (void) viewDidLoad
{
    [self updateForOrientation];
}

- (void)updateForOrientation
{
    if (UIInterfaceOrientationIsPortrait([[UIDevice currentDevice] orientation])) // became portrait
    {
        NSLog(@"is portrait");
        //code for changing layout to portrait position
    }

    else //became horiztontal
    {
        NSLog(@"is horizontal");
        //code for changing layout to horizontal position
    }
}

---

Output: is horizontal (this is the output whether it starts up as portrait or landscape)

推荐答案

问题是，您正在根据UIDeviceOrientation枚举将设备方向发送给期望UIInterfaceOrientation值的函数.

The problem is that you're sending the devices orientation in terms of the UIDeviceOrientation enum to a function that's expecting a UIInterfaceOrientation value.

如果命令单击UIInterfaceOrientationIsPortrait()，则可以看到它的定义如下.

If you command click on UIInterfaceOrientationIsPortrait(), you can see that it is defined as follows.

#define UIInterfaceOrientationIsPortrait(orientation)  ((orientation) == UIInterfaceOrientationPortrait || (orientation) == UIInterfaceOrientationPortraitUpsideDown)

如果您查看两种方向类型的枚举声明(下面的文档链接)，您会发现由于设备方向包含无"值而导致值不对齐.无论如何，将代码更改为使用UIInterfaceOrientation应该可以解决此问题.示例:

And if you look at the enum declarations for the two orientation types (documentation links below), you can see that there is a misalignment in value due to the device orientation containing a value for "none". Anyway, changing your code to use UIInterfaceOrientation should sort this out. Example:

- (void)updateForOrientation
{
    UIInterfaceOrientation currentOrientation = self.interfaceOrientation;

    if (UIInterfaceOrientationIsPortrait(currentOrientation)) {
        NSLog(@"is portrait");
    }else{
        NSLog(@"is horizontal");
    }
}

查看全文