遇到这样一个需求：应用无论处于哪个view controller，摇动手机，都能够出发某一方法。
能够想到的思路就是用苹果封装好的“MotionEvent”，但是如果简单的把一下代码加到某一view controller中，那么只有在该view controller展示在前端时，摇动手机才会出发方法。
- (BOOL)canBecomeFirstResponder {//默认是NO，所以得重写此方法，设成YES
return YES;
}
然后实现下列方法://很像TouchEvent事件
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
}
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
NSLog(@"shake");
}
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
}
解决方法：用Category扩展UIWindow，代码如下：
UIWindow+.h
#import <UIKit/UIKit.h> #define UIEventSubtypeMotionShakeNotification @"UIEventSubtypeMotionShakeNotification" @interface UIWindow (Motion) // @override
- (BOOL)canBecomeFirstResponder;
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event; @end
UIWindow+.m
#import "UIWindow+.h" @implementation UIWindow (Motion)
- (BOOL)canBecomeFirstResponder {//默认是NO，所以得重写此方法，设成YES
return YES;
} 然后实现下列方法://很像TouchEvent事件 - (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
} - (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
NSLog(@"shake");
} - (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
} @end