问题问的是如何用返回键来做，但我认为这可以帮助那些想要在使用UITextView时让键盘消失的人:

private func addToolBarForTextView() {
    let textViewToolbar: UIToolbar = UIToolbar()
    textViewToolbar.barStyle = .default
    textViewToolbar.items = [
        UIBarButtonItem(title: "Cancel", style: .done,
                  target: self, action: #selector(cancelInput)),
        UIBarButtonItem(barButtonSystemItem: .flexibleSpace,
                  target: self, action: nil),
        UIBarButtonItem(title: "Post Reply", style: .done,
                  target: self, action: #selector(doneInput))
    ]
    textViewToolbar.sizeToFit()
    yourTextView.inputAccessoryView = textViewToolbar
}

@objc func cancelInput() { print("cancel") }
@objc func doneInput() { print("done") }

override func viewDidLoad() {
    super.viewDidLoad()
    addToolBarForTextView()
}

在viewDidLoad或其他生命周期方法中调用addToolBarForTextView()。

这对我来说似乎是一个完美的解决方案。

欢呼,

穆拉特

我使用这段代码来更改响应器。

 - (BOOL)textView:(UITextView*) textView shouldChangeTextInRange: (NSRange) range replacementText: (NSString*) text
    {
        if ([text isEqualToString:@"\n"]) {
            //[textView resignFirstResponder];
            //return YES;
            NSInteger nextTag = textView.tag + 1;
            // Try to find next responder
            UIResponder* nextResponder = [self.view viewWithTag:nextTag];
            if (nextResponder) {
                // Found next responder, so set it.
                [nextResponder becomeFirstResponder];
            } else {
                // Not found, so remove keyboard.
                [textView resignFirstResponder];
            }
            return NO; 


            return NO;
        }
        return YES;

    }

我想我应该把这个片段放在这里:

确保声明了对UITextViewDelegate协议的支持。

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {

    if([text isEqualToString:@"\n"]) {
        [textView resignFirstResponder];
        return NO;
    }

    return YES;
}

Swift 4.0更新:

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    if text == "\n" {
        textView.resignFirstResponder()
        return false
    }
    return true
}

//你可以使用这个…

步骤1。第一步是确保声明了对UITextViewDelegate协议的支持。这是在你的头文件中完成的，例如这里的头文件叫做

EditorController。h:

@interface EditorController : UIViewController  {
  UITextView *messageTextView;
}

@property (nonatomic, retain) UITextView *messageTextView;

@end

步骤2。接下来你需要将控制器注册为UITextView的委托。从上面的例子继续，这里是我如何用EditorController作为委托初始化UITextView…

- (id) init {
    if (self = [super init]) {
        // define the area and location for the UITextView
        CGRect tfFrame = CGRectMake(10, 10, 300, 100);
        messageTextView = [[UITextView alloc] initWithFrame:tfFrame];
        // make sure that it is editable
        messageTextView.editable = YES;

        // add the controller as the delegate
        messageTextView.delegate = self;
    }

步骤3。现在拼图的最后一块是采取行动响应shouldCahngeTextInRange消息如下:

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range 
  replacementText:(NSString *)text
{
    // Any new character added is passed in as the "text" parameter
    if ([text isEqualToString:@"\n"]) {
        // Be sure to test for equality using the "isEqualToString" message
        [textView resignFirstResponder];

        // Return FALSE so that the final '\n' character doesn't get added
        return FALSE;
    }
    // For any other character return TRUE so that the text gets added to the view
    return TRUE;
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField; // called from textfield (keyboard)

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text; // good tester function - thanks

一种更优雅的方法是，当用户点击键盘框架之外的某个地方时，取消键盘。

首先，在UIBuilder的标识检查器中将你的ViewController的视图设置为类“UIControl”。control -拖动视图到ViewController的头文件中，并将其链接为Touch Up Inside事件的动作，例如:

ViewController。h

-(IBAction)dismissKeyboardOnTap:(id)sender;

在ViewController主文件中，ViewController.m:

-(IBAction)dismissKeyboardOnTap:(id)sender
    {
         [[self view] endEditing:YES];
    }

你可以使用类似的技术要求双击或长触。你可能需要设置你的ViewController为一个UITextViewDelegate，并将TextView连接到ViewController。这个方法对UITextView和UITextField都有效。

来源:Big Nerd Ranch

编辑:我还想补充一点，如果你正在使用UIScrollView，上述技术可能不容易通过接口构建器工作。在这种情况下，你可以使用一个UIGestureRecognizer并调用其中的[[self view] enditing:YES]方法。一个例子是:

-(void)ViewDidLoad{
    ....
    UITapGestureRecognizer *tapRec = [[UITapGestureRecognizer alloc] 
        initWithTarget:self action:@selector(tap:)];
    [self.view addGestureRecognizer: tapRec];
    ....
}

-(void)tap:(UITapGestureRecognizer *)tapRec{
    [[self view] endEditing: YES];
}

当用户在键盘外点击，并且没有点击输入空间时，键盘将关闭。