直接上代码：

////  RootViewController.m//  UIText_test////#import "RootViewController.h"#import 
      
           /// 用户视觉反馈@interface RootViewController ()
       
        @property (nonatomic, strong) UIToolbar *toolBar ;@property (nonatomic, strong) UITextView *textView ;@end@implementation RootViewController- (UIToolbar *)toolBar {    if (!_toolBar) {        self.toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 375, 30)];        [_toolBar setBarStyle:UIBarStyleBlack];        UIBarButtonItem *oneButton = [[UIBarButtonItem alloc] initWithTitle:@"開始" style:UIBarButtonItemStyleDone target:self action:nil];        UIBarButtonItem *twoButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:self action:nil];        UIBarButtonItem *threeButton = [[UIBarButtonItem alloc] initWithTitle:@"完毕" style:UIBarButtonItemStyleDone target:self action:@selector(handleThreeBtn)];        NSArray *buttonArray = [NSArray arrayWithObjects:oneButton, twoButton, threeButton, nil];        [_toolBar setItems:buttonArray]; // 加入到 toolBar 上    }    return _toolBar;}- (UITextView *)textView {    if (!_textView) {        self.textView = [[UITextView alloc] initWithFrame:CGRectMake(5, 200, 375, 190)];        _textView.textColor = [UIColor redColor];        _textView.font = [UIFont systemFontOfSize:20];        _textView.delegate = self;        [_textView.layer setCornerRadius:10];  // 设置成圆角        _textView.backgroundColor = [UIColor cyanColor];        _textView.text = @"sfjlegjklaeyg a";        _textView.scrollEnabled = YES;        _textView.autoresizingMask = UIViewAutoresizingFlexibleHeight ; // 自适应高度        [_textView setInputAccessoryView:self.toolBar];  // 设置辅助视图    }    return _textView;}- (void)viewDidLoad {    [super viewDidLoad];    [self.view addSubview:self.textView];    // 自己定义菜单项    UIMenuItem *menuItem = [[UIMenuItem alloc] initWithTitle:@"分享到新浪微博" action:@selector(changeColor)];    UIMenuController *menu = [UIMenuController sharedMenuController];    [menu setMenuItems:[NSArray arrayWithObject:menuItem]]; //加入}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}#pragma mark - Action -- (void)handleThreeBtn {    [self.textView resignFirstResponder];    // 撤销第一次响应}- (void)changeColor {    self.view.backgroundColor = [UIColor colorWithRed:arc4random() % 256 / 255.0 green:arc4random() % 256 / 255.0 blue:arc4random() % 256 / 255.0 alpha:1];}- (void)handleDone {    [self.textView resignFirstResponder]; // 撤销第一响应}#pragma mark - UITextViewDelegate -// 完毕開始编辑- (void)textViewDidBeginEditing:(UITextView *)textView {    UIBarButtonItem *done = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(handleDone)];    self.navigationItem.rightBarButtonItem = done;}// 完毕结束编辑- (void)textViewDidEndEditing:(UITextView *)textView {    self.navigationItem.rightBarButtonItem = nil;   /// 导航条按钮设置为空}// 当文本发生改变时- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {    if ([text isEqual:@"\n"]) {        [textView resignFirstResponder];        return NO;    }    return YES;}@end