ios文本框随键盘提升

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UITextFieldDelegate>{
UIScrollView * _scrollView;
    IBOutlet UITextField *message;
    IBOutlet UIScrollView *myScrollView;
}
@property (retain, nonatomic) IBOutlet UITextField *message;
@property (retain, nonatomic) IBOutlet UIScrollView *myScrollView;
@end

//
//  ViewController.m
//  ChatRoom007
//
//  Created by Bo Xiu on 12-9-14.
//  Copyright (c) 2012年 Bo Xiu. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController
@synthesize myScrollView;
@synthesize message;
- (void)viewDidLoad
{
    [super viewDidLoad];
    UIView *myView =  [self bubbleView:@"hello" from:NO];
    [self.view addSubview:myView];
    message.delegate = self;
}

//该方法为点击输入文本框要开始输入是调用的代理方法：就是把view上移到能看见文本框的地方
- (void)textFieldDidBeginEditing:(UITextField *)textField{
    CGFloat keyboardHeight = 216.0f;
    if (self.view.frame.size.height - keyboardHeight <= textField.frame.origin.y + textField.frame.size.height) {
        CGFloat y = textField.frame.origin.y - (self.view.frame.size.height - keyboardHeight - textField.frame.size.height - 5);
        [UIView beginAnimations:@"srcollView" context:nil];
        [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
        [UIView setAnimationDuration:0.275f];
        self.view.frame = CGRectMake(self.view.frame.origin.x, -y, self.view.frame.size.width, self.view.frame.size.height);
        [UIView commitAnimations];
    }
}

//该方法为点击虚拟键盘Return，要调用的代理方法：隐藏虚拟键盘
- (BOOL)textFieldShouldReturn:(UITextField *)textField{
    [textField resignFirstResponder];
    return YES;
}

//该方法为完成输入后要调用的代理方法：虚拟键盘隐藏后，要恢复到之前的文本框地方
- (void)textFieldDidEndEditing:(UITextField *)textField{
    [UIView beginAnimations:@"srcollView" context:nil];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationDuration:0.275f];
    self.view.frame = CGRectMake(self.view.frame.origin.x, 0, self.view.frame.size.width, self.view.frame.size.height);
    [UIView commitAnimations];
}

#pragma mark Table view methods
- (UIView *)bubbleView:(NSString *)text from:(BOOL)fromSelf {
	// build single chat bubble cell with given text
	UIView *returnView = [[UIView alloc] initWithFrame:CGRectZero];
	returnView.backgroundColor = [UIColor clearColor];
    
	UIImage *bubble = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:fromSelf?@"bubbleSelf":@"bubble" ofType:@"png"]];
	UIImageView *bubbleImageView = [[UIImageView alloc] initWithImage:[bubble stretchableImageWithLeftCapWidth:21 topCapHeight:14]];
    
	UIFont *font = [UIFont systemFontOfSize:12];
	CGSize size = [text sizeWithFont:font constrainedToSize:CGSizeMake(150.0f, 1000.0f) lineBreakMode:UILineBreakModeCharacterWrap];
    
	UILabel *bubbleText = [[UILabel alloc] initWithFrame:CGRectMake(21.0f, 14.0f, size.width+10, size.height+10)];
	bubbleText.backgroundColor = [UIColor clearColor];
	bubbleText.font = font;
	bubbleText.numberOfLines = 0;
	bubbleText.lineBreakMode = UILineBreakModeCharacterWrap;
	bubbleText.text = text;
	
	bubbleImageView.frame = CGRectMake(0.0f, 0.0f, 200.0f, size.height+40.0f);
	if(fromSelf)
		returnView.frame = CGRectMake(120.0f, 10.0f, 200.0f, size.height+50.0f);
	else
		returnView.frame = CGRectMake(0.0f, 10.0f, 200.0f, size.height+50.0f);
	
	[returnView addSubview:bubbleImageView];
	[bubbleImageView release];
	[returnView addSubview:bubbleText];
	[bubbleText release];
    
	return [returnView autorelease];
}

- (void)viewDidUnload
{
    [message release];
    message = nil;
    [myScrollView release];
    myScrollView = nil;
    [super viewDidUnload];
    // Release any retained subviews of the main view.
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
        return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
    } else {
        return YES;
    }
}

- (void)dealloc {
    [message release];
    [myScrollView release];
    [super dealloc];
}
@end