UITextField被键盘遮挡问题解决方法

文连接： 
http://www.devdiv.com/thread-70159-1-1.html 

实现以下三个方法，如果弹出的键盘会遮住输入框 ，整体的界面会向上移动，这样就不会遮住输入框了。自己增加UITextFieldDelegate委托。 
只适合iPhone,如果想要支持iPad,只要把216改成iPad上面键盘的高度即可。 

C代码  

1. - (void)keyboardWillShow:(NSNotification *)noti  
2. {          
3.         //键盘输入的界面调整          
4.         //键盘的高度  
5.         float height = 216.0;                  
6.         CGRect frame = self.view.frame;          
7.         frame.size = CGSizeMake(frame.size.width, frame.size.height - height);          
8.         [UIView beginAnimations:@"Curl"context:nil];//动画开始            
9.         [UIView setAnimationDuration:0.30];             
10.         [UIView setAnimationDelegate:self];            
11.         [self.view setFrame:frame];           
12.         [UIView commitAnimations];           
13. }  
14.   
15.   
16. - (BOOL)textFieldShouldReturn:(UITextField *)textField   
17. {          
18.     // When the user presses return, take focus away from the text field so that the keyboard is dismissed.          
19.     NSTimeInterval animationDuration = 0.30f;          
20.     [UIView beginAnimations:@"ResizeForKeyboard" context:nil];          
21.     [UIView setAnimationDuration:animationDuration];          
22.     CGRect rect = CGRectMake(0.0f, 0.0f, self.view.frame.size.width, self.view.frame.size.height);          
23.     self.view.frame = rect;          
24.     [UIView commitAnimations];          
25.     [textField resignFirstResponder];  
26.     return YES;          
27. }  
28.   
29. - (void)textFieldDidBeginEditing:(UITextField *)textField  
30. {          
31.         CGRect frame = textField.frame;  
32.         int offset = frame.origin.y + 32 - (self.view.frame.size.height - 216.0);//键盘高度216  
33.         NSTimeInterval animationDuration = 0.30f;                  
34.         [UIView beginAnimations:@"ResizeForKeyBoard" context:nil];                  
35.         [UIView setAnimationDuration:animationDuration];  
36.         float width = self.view.frame.size.width;                  
37.         float height = self.view.frame.size.height;          
38.         if(offset > 0)  
39.         {  
40.                 CGRect rect = CGRectMake(0.0f, -offset,width,height);                  
41.                 self.view.frame = rect;          
42.         }          
43.         [UIView commitAnimations];                  
44. }  

以下转自   http://janedoneway.iteye.com/blog/1575250

另外我自己做了一点修改： 
在实际用的时候，键盘消失原来的控件并没有回归都原来的位置，而是上移了20个像素，我估计是因为顶部Bar的原因，只要将22行代码改成如下就可以了： 
CGRect rect = CGRectMake(0.0f, 20.0f, self.view.frame.size.width, self.view.frame.size.height);