//监听键盘的通知

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];

- (void)keyboardWillShow:(NSNotification *)notification {

    /*

     Reduce the size of the text view so that it's not obscured by the keyboard.

     Animate the resize so that it's in sync with the appearance of the keyboard.

     */

    NSDictionary *userInfo = [notification userInfo];

    // Get the origin of the keyboard when it's displayed.

    NSValue* aValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];

    // Get the top of the keyboard as the y coordinate of its origin in self's view's coordinate system. The bottom of the text view's frame should align with the top of the keyboard's final position.

    CGRect keyboardRect = [aValue CGRectValue];

    keyboardRect = [self.view convertRect:keyboardRect fromView:nil];

    CGFloat keyboardTop = keyboardRect.origin.y;

    CGRect newTextViewFrame = self.view.bounds;

    newTextViewFrame.size.height = keyboardTop - self.view.bounds.origin.y;

    // Get the duration of the animation.

    NSValue *animationDurationValue = [userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey];

    NSTimeInterval animationDuration;

    [animationDurationValue getValue:&animationDuration];

    // Animate the resize of the text view's frame in sync with the keyboard's appearance.

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDuration:animationDuration];

    self.reportTableView.frame = newTextViewFrame;

    [UIView commitAnimations];

}

- (void)keyboardWillHide:(NSNotification *)notification {

    NSDictionary* userInfo = [notification userInfo];

    /*

     Restore the size of the text view (fill self's view).

     Animate the resize so that it's in sync with the disappearance of the keyboard.

     */

    NSValue *animationDurationValue = [userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey];

    NSTimeInterval animationDuration;

    [animationDurationValue getValue:&animationDuration];

    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDuration:animationDuration];

    self.reportTableView.frame = CGRectMake(, , [UIScreen mainScreen].bounds.size.width,[UIScreen mainScreen].bounds.size.height  -  - );

    [UIView commitAnimations];

}

     [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];

-(void)dealloc

{

    [[NSNotificationCenter defaultCenter] removeObserver:self name:nil object:nil];

}