UITextView记录

1. 创建一个uitextview的视图对象并设置代理
2. 实现代理方法：
   高度自适应

-(void)textViewDidChange:(UITextView *)textView{   
    //设置最大的高度
      static CGFloat maxHeight = 500;    
      CGFloat width   = textView.width;   
      CGSize newSize  = [textView sizeThatFits:CGSizeMake(width,MAXFLOAT)];   
      CGRect newFrame = textView.frame;    
      //大于对大高度是设置为可滚动   
      if (newSize.height>=maxHeight) {        
          newSize.height = maxHeight;
          textView.scrollEnabled = YES;   
      }else{
          textView.scrollEnabled = NO;
      } 
      newFrame.size = newSize;    textView.frame= newFrame;
}

点击return时隐藏键盘

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString*)text{  
    if ([text isEqualToString:@"\n"]) {            
         [textView resignFirstResponder];               
          return NO;   
     }    
      return YES;
}