iOS摇一摇的实现

把下边的代* 放到UIVIEWCONTROLLER里，就能实现摇一摇效果

- (BOOL) canBecomeFirstResponder
{
    return YES;
}
- (void) viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    [self becomeFirstResponder];
}
- (void) viewWillAppear:(BOOL)animated
{
    [self resignFirstResponder];
    [super viewWillAppear:animated];
}
- (void) motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
    if (motion == UIEventSubtypeMotionShake) {
        NSLog(@"Shake..........");
    }
}