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);
}

对于开放式键盘：

InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
imm.showSoftInput(edtView, InputMethodManager.SHOW_IMPLICIT);

对于关闭/隐藏键盘：

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

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)
    }

更新：我不知道为什么这个解决方案不再有效（我刚刚在Android 23上测试过）。请改用Saurabh Pareek的溶液。这里是：

InputMethodManager imm = (InputMethodManager) getSystemService(Activity.INPUT_METHOD_SERVICE);
//Hide:
imm.toggleSoftInput(InputMethodManager.HIDE_IMPLICIT_ONLY, 0);
//Show
imm.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0);

旧答案：

//Show soft-keyboard:
getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
//hide keyboard :
 getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

在Kotlin中，只需使用这两种方法来显示和隐藏键盘。

fun showKeyboard() =
    (context.getSystemService(AppCompatActivity.INPUT_METHOD_SERVICE) as? InputMethodManager)!!
        .toggleSoftInput(InputMethodManager.SHOW_FORCED, 0)

fun hideKeyboard(view: View) =
    (context.getSystemService(AppCompatActivity.INPUT_METHOD_SERVICE) as? InputMethodManager)!!
        .hideSoftInputFromWindow(view.windowToken, 0)

这里的视图是您当前的视图，

一些科特林代码：

从“活动”中隐藏键盘：

(currentFocus ?: View(this))
            .apply { (getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager)
                        .hideSoftInputFromWindow(windowToken, 0) }