2. UITextView退出键盘的几种方式因为你点击UITextView会出现键盘，如果你退出键盘，有如下几种方式：（1）如果你程序是有导航条的，可以在导航条上面加多一个Done的按钮，用来退出键盘，当然要先实UITextViewDelegate。代码如下：- (void)textViewDidBeginEditing:(UITextView *)textView {      UIBarButtonItem *done =    [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(leaveEditMode)] autorelease];      self.navigationItem.rightBarButtonItem = done;       }- (void)textViewDidEndEditing:(UITextView *)textView {      self.navigationItem.rightBarButtonItem = nil;   }- (void)leaveEditMode {      [self.textView resignFirstResponder];   } （2）如果你的textview里不用回车键，可以把回车键当做退出键盘的响应键。代码如下：#pragma mark - UITextView Delegate Methods   -(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text  {      if ([text isEqualToString:@"\n"]) {          [textView resignFirstResponder];          return NO;      }      return YES;  } 这样无论你是使用电脑键盘上的回车键还是使用弹出键盘里的return键都可以达到退出键盘的效果。（3）还有你也可以自定义其他加载键盘上面用来退出，比如在弹出的键盘上面加一个view来放置退出键盘的Done按钮。代码如下： UIToolbar * topView = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 30)];      [topView setBarStyle:UIBarStyleBlack];      UIBarButtonItem * helloButton = [[UIBarButtonItem alloc]initWithTitle:@"Hello" style:UIBarButtonItemStyleBordered target:self action:nil];            UIBarButtonItem * btnSpace = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];      UIBarButtonItem * doneButton = [[UIBarButtonItem alloc]initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(dismissKeyBoard)];      NSArray * buttonsArray = [NSArray arrayWithObjects:helloButton,btnSpace,doneButton,nil];      [doneButton release];      [btnSpace release];      [helloButton release];      [topView setItems:buttonsArray];      [tvTextView setInputAccessoryView:topView];  -(IBAction)dismissKeyBoard  {      [tvTextView resignFirstResponder];  } （4）设置UITextView圆角问题做法是在 #import QuartzCore/QuartzCore.h 后，便能調用 [textView.layer setCornerRadius:10]; 來把 UITextView 设定圓角（5）UITextView根据文本大小自适应高度通过实现文本字数来确定高度，如下：NSString * desc = @"Description it is  a test font, and don't become angry for which i use to do here.Now here is a very nice party from american or not!";  CGSize  size = [desc sizeWithFont:[UIFont systemFontOfSize:14] constrainedToSize:CGSizeMake(240, 2000) lineBreakMode:UILineBreakModeWordWrap]; 然后需要定义UITextView的numberoflines为0，即不做行数的限制。如下：[textView setNumberOfLines:0];  [textView setFrame:CGRectMake(40, 135, 240, size.height+10)];  [textView setText:desc];  （6）UITextView自定选择文字后的菜单在ViewDidLoad中加入：UIMenuItem *menuItem = [[UIMenuItem alloc]initWithTitle:@"分享到新浪微博" action:@selector(changeColor:)];UIMenuController *menu = [UIMenuController sharedMenuController];[menu setMenuItems:[NSArray arrayWithObject:menuItem]];[menuItem release];当然上面那个@selector里面的changeColor方法还是自己写吧，也就是说点击了我们自定义的菜单项后会触发的方法。然后还得在代码里加上一个方法：-(BOOL)canPerformAction:(SEL)action withSender:(id)sender{if(action == @selector(changeColor:)){if(textView.selectedRange.length>0)return YES;}return NO;}