http://bbs.yusian.com/thread-10352-1-1.html 原文地址
问题分析:iOS8在调用系统相机拍照时,会有一两秒的停顿,然后再弹出UIImagePickConroller,IOS7是没有这个问题的,在百度找了无数遍都没能解决这个问题,有说要将imagePickController设置为全局变量,有说要延时0.5秒再presentViewController的,各显神通,但很遗憾的都没能解决这个问题,今天特意单独写个Demo来研究此问题,终于取得了突破性的进展!
其实根本原因不在于系统拍照控制器上面,而是执行presentViewController这个动作本身!我们可以查看下UIViewController这个类,他有一个属性
[Objective-C] 纯文本查看 复制代码
@property ( nonatomic ,assign)
UIModalPresentationStyle modalPresentationStyle NS_AVAILABLE_IOS (3_2); |
[Objective-C] 纯文本查看 复制代码
typedef
NS_ENUM ( NSInteger ,
UIModalPresentationStyle) { UIModalPresentationFullScreen
= 0, #if
__IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_3_2 UIModalPresentationPageSheet, UIModalPresentationFormSheet, UIModalPresentationCurrentContext, #endif #if
__IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_7_0 UIModalPresentationCustom, UIModalPresentationNone
= -1, #endif
}; |
[Objective-C] 纯文本查看 复制代码
typedef
NS_ENUM ( NSInteger ,
UIModalPresentationStyle) { UIModalPresentationFullScreen
= 0, UIModalPresentationPageSheet
NS_ENUM_AVAILABLE_IOS (3_2), UIModalPresentationFormSheet
NS_ENUM_AVAILABLE_IOS (3_2), UIModalPresentationCurrentContext
NS_ENUM_AVAILABLE_IOS (3_2), UIModalPresentationCustom
NS_ENUM_AVAILABLE_IOS (7_0), UIModalPresentationOverFullScreen
NS_ENUM_AVAILABLE_IOS (8_0), UIModalPresentationOverCurrentContext
NS_ENUM_AVAILABLE_IOS (8_0), UIModalPresentationPopover
NS_ENUM_AVAILABLE_IOS (8_0), UIModalPresentationNone
NS_ENUM_AVAILABLE_IOS (7_0)
= -1, }; |
[Objective-C] 纯文本查看 复制代码
if
([[[UIDevice currentDevice] systemVersion] floatValue]>=8.0) { self .modalPresentationStyle=UIModalPresentationOverCurrentContext; } |