完美解决ios4与ios5输入框随键盘移动问题

iOS5中当键盘输入法切换到中文时，键盘高度由216增加到252像素。这一变化将遮住输入框。如何才能解决这一问题呢？

      在iOS5中，新增有notification（UIKeyboardWillChangeFrameNotification）可以用来监测键盘frame的变化。在iOS4中，可以通过UIKeyboardWillShowNotification以及UIKeyboardWillHideNotification来监测键盘的显示与隐藏事件。综合处理下，可以用以下方法解决：

#ifndef IOS_VERSION  
#define IOS_VERSION [[[UIDevice currentDevice] systemVersion] floatValue]  
#endif  

在viewdidload中注册监测事件：

if (IOS_VERSION < 5.0) {  
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrame:) name:UIKeyboardWillShowNotification object:nil];  
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrame:) name:UIKeyboardWillHideNotification object:nil];  
}else{  
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrame:) name:UIKeyboardWillChangeFrameNotification object:nil];  
}  

在dealloc中移除监测事件：

if (IOS_VERSION < 5.0) {  
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];  
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];  
}else{  
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillChangeFrameNotification object:nil];  
} 

事件处理函数：

- (void)keyboardWillChangeFrame:(NSNotification *)notification{  
    if(!isDisplayFaceBox){  
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_3_2  
        if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {  
#endif  
#if __IPHONE_OS_VERSION_MIN_REQUIRED >= __IPHONE_3_2  
            NSValue *keyboardBoundsValue = [[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey];  
#else  
            NSValue *keyboardBoundsValue = [[notification userInfo] objectForKey:UIKeyboardBoundsUserInfoKey];  
#endif  
            CGRect keyboardBounds;  
            [keyboardBoundsValue getValue:&keyboardBounds];  
            //UIEdgeInsets e = UIEdgeInsetsMake(0, 0, keyboardBounds.size.height, 0);  
            //[keyboardScrollView setScrollIndicatorInsets:e];  
            //[keyboardScrollView setContentInset:e];  
              
            NSInteger offset = 480-keyboardBounds.origin.y;  
            CGRect listFrame = CGRectMake(0, offset, 320, 377-offset);  
              
            [UIView beginAnimations:@"anim" context:NULL];  
            [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];  
            [UIView setAnimationBeginsFromCurrentState:YES];  
            [UIView setAnimationDuration:0.3];  
            //处理移动事件，将各视图设置最终要达到的状态  
            [tableviewbo setFrame:listFrame];  
              
            faceButton.hidden = NO;  
            keyboardButton.hidden = YES;      
              
            [keyboardScrollView setContentOffset:CGPointMake(0, offset) animated:NO];  
              
            [self scrollToBottomAnimated:NO];  
              
            [UIView commitAnimations];  
              
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_3_2  
        }  
#endif  
    }  
}

原文地址：http://blog.csdn.net/zengconggen/article/details/7071086