使用AndroidX，我们将获得一种惊人的显示/隐藏键盘的方法。阅读发行说明-1.5.0-alpha02。现在如何隐藏/显示键盘

val controller = view.windowInsetsController

// Show the keyboard
controller.show(Type.ime())
// Hide the keyboard
controller.hide(Type.ime())

链接我自己的答案如何在Android中检查软件键盘的可见性？以及一个包含更多变化（甚至更多）的惊人博客。

这是我的工作。这是在Kotlin隐藏键盘。

private fun hideKeyboard() {
        val inputManager = activity?.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        val focusedView = activity?.currentFocus
        if (focusedView != null) {
            inputManager.hideSoftInputFromWindow(focusedView.windowToken,
                    InputMethodManager.HIDE_NOT_ALWAYS)
        }
    }

下面是隐藏和显示方法。

科特林

fun hideKeyboard(activity: Activity) {
    val v = activity.currentFocus
    val imm = activity.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
    assert(v != null)
    imm.hideSoftInputFromWindow(v!!.windowToken, InputMethodManager.HIDE_NOT_ALWAYS)
}

private fun showKeyboard(activity: Activity) {
    val v = activity.currentFocus
    val imm = activity.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
    assert(v != null)
    imm.showSoftInput(v, InputMethodManager.SHOW_IMPLICIT)
}

Java

public static void hideKeyboard(Activity activity) {
    View v = activity.getCurrentFocus();
    InputMethodManager imm = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
    assert imm != null && v != null;
    imm.hideSoftInputFromWindow(v.getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
}

private static void showKeyboard(Activity activity) {
    View v = activity.getCurrentFocus();
    InputMethodManager imm = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
    assert imm != null && v != null;
    imm.showSoftInput(v, InputMethodManager.SHOW_IMPLICIT);
}

在Kotlin

fun hideKeyboard(activity: BaseActivity) {
        val view = activity.currentFocus?: View(activity)
        val imm = activity.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.hideSoftInputFromWindow(view.windowToken, 0)
    }

只需在BaseActivity和BaseFragment中为整个应用程序创建通用方法

在onCreate（）中初始化inputMethodManager

inputMethodManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);

使用此方法隐藏和显示键盘

public void hideKeyBoard(View view) {
     if (view != null) {
         inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(), 0);
      }
 }

public void showKeyboard(View view, boolean isForceToShow) {
      if (isForceToShow)
         inputMethodManager.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);
      else if (view != null)
           inputMethodManager.showSoftInput(view, 0);
}

Kotlin中的Wiki答案：

1-在文件中创建顶级函数（例如，包含所有顶级函数的文件）：

fun Activity.hideKeyboard(){
    val imm = this.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
    var view = currentFocus
    if (view == null) { view = View(this) }
    imm.hideSoftInputFromWindow(view.windowToken, 0)
}

2-然后在你需要的任何活动中调用它：

this.hideKeyboard()