如果要使用Java代码隐藏键盘，请使用以下命令：

  InputMethodManager imm = (InputMethodManager)this.getSystemService(Context.INPUT_METHOD_SERVICE);
  imm.hideSoftInputFromWindow(fEmail.getWindowToken(), 0);

或者，如果您希望始终隐藏键盘，请在AndroidManifest中使用此选项：

 <activity
 android:name=".activities.MyActivity"
 android:configChanges="keyboardHidden"  />

如果你使用Kotlin开发你的应用程序，这真的很容易做到。

添加此扩展功能：

对于活动：

fun Activity.hideKeyboard() {
    val inputManager = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
    val view = currentFocus
    if (view != null) {
        inputManager.hideSoftInputFromWindow(view.windowToken, InputMethodManager.HIDE_NOT_ALWAYS)
    }
}

对于片段：

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

现在，您可以简单地调用片段或活动：

 hideKeyboard()

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

public final class UtilsKeyboard {
/**
 * Sets the cursor at the end of this edit text and shows a keyboard
 */
public static void focusKeyboard(@NonNull EditText editText) {
    editText.requestFocus();
    editText.setSelection(editText.getText().length());
    showKeyboard(editText);
}

private static void showKeyboard(@NonNull View view) {
    final InputMethodManager manager = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
    if (manager != null) {
        manager.showSoftInput(view, InputMethodManager.SHOW_FORCED);
    }
}

public static boolean hideKeyboard(@NonNull Window window) {
    View view = window.getCurrentFocus();
    return hideKeyboard(window, view);
}

private static boolean hideKeyboard(@NonNull Window window, @Nullable View view) {
    if (view == null) {
        return false;
    }
    InputMethodManager inputMethodManager = (InputMethodManager) window.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
    if (inputMethodManager != null) {
        return inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(), 0);
    }
    return false;
}

public static boolean hideKeyboard(@Nullable View view) {
    if (view == null) {
        return false;
    }
    InputMethodManager inputMethodManager = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
    if (inputMethodManager != null) {
        return inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(), 0);
    }
    return false;
}

/**
 * This will hide the keyboard and unfocus any focused view.
 */
public static void unfocusKeyboard(@NonNull Window window) {
    // When showing the bottom menu, make sure the keyboard isn't and that no view has focus
    hideKeyboard(window);
    final View focused = window.getCurrentFocus();
    if (focused != null) focused.clearFocus();
}}

嗨，这很简单，如果您使用Kotlin，我相信您可以在活动中轻松地将代码转换为Java。当您的活动被加载时，例如在onCreate（）调用它时，请使用此函数。

fun hideKeybord (){
val inputManager = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
if (inputManager.isAcceptingText){
    inputManager.hideSoftInputFromWindow(currentFocus.windowToken, 0)
}

}

正如我所提到的，在onCreate（）方法中调用此函数，然后将此android:windowSoftInputMode=“stateAlwaysHidden”行添加到manafist.xml文件中的活动中。。。

<activity
    android:name=".Activity.MainActivity"
    android:label="@string/app_name"
    android:theme="@style/AppTheme.NoActionBar"
    android:windowSoftInputMode="stateAlwaysHidden">

您可以使用下面的扩展来隐藏和显示软键盘

fun Fragment.showKeyboard(view: View) {
    view.isFocusableInTouchMode = true
    view.requestFocus()
    val imm = view.context?.getSystemService(Context.INPUT_METHOD_SERVICE) 
        as InputMethodManager
    imm.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT) }

fun Fragment.hideKeyboard(view: View) {
    view.clearFocus()
    val imm = view.context?.getSystemService(Context.INPUT_METHOD_SERVICE) 
       as InputMethodManager
    imm.hideSoftInputFromWindow(view.windowToken, 0) }

要调用扩展，只需按照以下片段进行操作

showKeyboard(Your edittext ID)

hideKeboard(Your edittext ID)