UITextView控件
创建UITextView的文件，并在.h文件中写入如下代码：
#import <UIKit/UIKit.h>
@interface TextViewController : UIViewController <UITextViewDelegate>{
UITextView *textView;
}
@property (nonatomic, retain) UITextView *textView;
@end
在.m文件中初始化这个textview，写入代码如下：
self.textView = [[[UITextView alloc] initWithFrame:self.view.frame] autorelease]; //初始化大小并自动释放
self.textView.textColor = [UIColor blackColor];//设置textview里面的字体颜色
self.textView.font = [UIFont fontWithName:@"Arial" size:18.0];//设置字体名字和字体大小
self.textView.delegate = self;//设置它的委托方法
self.textView.backgroundColor = [UIColor whiteColor];//设置它的背景颜色
self.textView.text = @"Now is the time for all good developers to come to serve their country.\n\nNow is the time for all good developers to come to serve their country.";//设置它显示的内容
self.textView.returnKeyType = UIReturnKeyDefault;//返回键的类型
self.textView.keyboardType = UIKeyboardTypeDefault;//键盘类型
self.textView.scrollEnabled = YES;//是否可以拖动
self.textView.autoresizingMask = UIViewAutoresizingFlexibleHeight;//自适应高度
[self.view addSubview: self.textView];//加入到整个页面中
文本字段实现了UITextInputTrait协议，其提供了7个属性来定义字段处理文本输入的方式：autocapitalizationType、autocorrectionType、enablesReturnKeyAutomatically、keyboardAppearance、keyboardType、returnKeyType、secureTextEntry。
其它，当文本字段为空时，placeholder文本以浅灰色显示，提供一个用户提示。通过设置clearButtonMode可以指定是否以及何时显示清除按钮。
2. UITextView退出键盘的几种方式
（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，当然要先实现UITextViewDelegate。
- (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。
#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;
}
（3）还有你也可以自定义其他视图控件加载到键盘上用来退出，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。
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
_textView.layer.cornerRadius = 8; //给图层的边框设置为圆角 _textView.layer.masksToBounds = YES;
给TextView加一个有色边框，并设置背景图片
//给图层添加一个有色边框
_textView.layer.borderWidth = 5;
_textView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09 blue:0.07 alpha:0.5] CGColor];
_textView.layer.contents = (id)[UIImage imageNamed:@"31"].CGImage; //给图层添加背景图片
（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];
只有UILabel需要定义的numberoflines为0，即不做行数的限制。如下：
[label setNumberOfLines:0];
[label setFrame:CGRectMake(40, 135, 240, size.height+10)];
[label setText:desc];
（6）UITextView自定选择文字后的菜单
在ViewDidLoad中加入：
- (void)viewDidLoad
{
[super viewDidLoad];
self._textView = [[UITextView alloc] initWithFrame:CGRectMake(10, 100, 300, 200)];//初始化
_textView.font = [UIFont fontWithName:@"Arial" size:33];//设置字体名字和字体大小
[self.view addSubview:_textView];
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) || action == @selector(copy:))
{
if(_textView.selectedRange.length>0)
return YES;
}
return NO;
}
-(void)changeColor
{
NSLog(@"%@",[_textView.text substringWithRange:_textView.selectedRange]);
}
实现后如下图：
获得行数(包括换行符也会计算在内)：
CGSize size = [[self.TextView text] sizeWithFont:[self.TextView font]];
// 2. 取出文字的高度
int length = size.height;
//3. 计算行数
int colomNumber = TextView.contentSize.height/length;