在Kotlin试试这个

 private fun hideKeyboard(){
    val imm = activity!!.getSystemService(INPUT_METHOD_SERVICE) as InputMethodManager
    imm.hideSoftInputFromWindow(activity!!.currentFocus!!.windowToken, 0)
}

在Java中尝试

 private void hideKeyboard(){
  InputMethodManager imm =(InputMethodManager)getSystemService(INPUT_METHOD_SERVICE);
  imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 0);
}

对于那些寻找喷气背包的人来说，写下答案。

val keyboardController = LocalSoftwareKeyboardController.current

//for showing the keyboard
keyboardController?.show()
//for hiding the keyboard
keyboardController?.hide()

在如此的搜索中，我找到了一个适合我的答案

// Show soft-keyboard:
InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);

// Hide soft-keyboard:
getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

这应该是有效的：

public class KeyBoard {

    public static void show(Activity activity){
        InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
        imm.toggleSoftInput(0, InputMethodManager.HIDE_IMPLICIT_ONLY); // show
    }

    public static void hide(Activity activity){
        InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
        imm.toggleSoftInput(InputMethodManager.HIDE_IMPLICIT_ONLY, 0); // hide
    }

    public static void toggle(Activity activity){
        InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
        if (imm.isActive()){
            hide(activity); 
        } else {
            show(activity); 
        }
    }
}

KeyBoard.toggle(activity);

这对我有用。

public static void hideKeyboard(Activity act, EditText et){
    Context c = act.getBaseContext();
    View v = et.findFocus();
    if(v == null)
        return;
    InputMethodManager inputManager = (InputMethodManager) c.getSystemService(Context.INPUT_METHOD_SERVICE);
    inputManager.hideSoftInputFromWindow(v.getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
}

如果有人感兴趣的话，我已经为Kotlin写了一个小扩展，但没有太多测试：

fun Fragment.hideKeyboard(context: Context = App.instance) {
    val windowToken = view?.rootView?.windowToken
    windowToken?.let {
        val imm = context.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.hideSoftInputFromWindow(windowToken, 0)
    }
}

App.instance是存储在Application中的静态“this”Application对象

更新：在某些情况下，windowToken为空。我增加了使用反射来检测键盘是否关闭的额外关闭方式

/**
 * If no window token is found, keyboard is checked using reflection to know if keyboard visibility toggle is needed
 *
 * @param useReflection - whether to use reflection in case of no window token or not
 */
fun Fragment.hideKeyboard(context: Context = MainApp.instance, useReflection: Boolean = true) {
    val windowToken = view?.rootView?.windowToken
    val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
    windowToken?.let {
        imm.hideSoftInputFromWindow(windowToken, 0)
    } ?: run {
        if (useReflection) {
            try {
                if (getKeyboardHeight(imm) > 0) {
                    imm.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS)
                }
            } catch (exception: Exception) {
                Timber.e(exception)
            }
        }
    }
}

fun getKeyboardHeight(imm: InputMethodManager): Int = InputMethodManager::class.java.getMethod("getInputMethodWindowVisibleHeight").invoke(imm) as Int