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)

public void setKeyboardVisibility(boolean show) {
    InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
    if(show){
        imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);
    }else{
        imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(),0);
    }
}

下面的代码将帮助您创建可以从任何地方调用的通用函数。

import android.app.Activity
import android.content.Context
import android.support.design.widget.Snackbar
import android.view.View
import android.view.inputmethod.InputMethodManager

public class KeyboardHider {
    companion object {

        fun hideKeyboard(view: View, context: Context) {
            val inputMethodManager = context.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
            inputMethodManager.hideSoftInputFromWindow(view.windowToken, 0)
        }

    }

}

使用一行代码从任何地方调用Above方法。

CustomSnackbar.hideKeyboard(view, this@ActivityName)

视图可以是任何内容，例如活动的根布局。

简单的方法家伙：试试这个。。。

private void closeKeyboard(boolean b) {

        View view = this.getCurrentFocus();

        if(b) {
            if (view != null) {
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
            }
        }
        else {
            InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
            imm.showSoftInput(view, 0);
        }
    }

只需在活动中使用此优化代码：

if (this.getCurrentFocus() != null) {
    InputMethodManager inputManager = (InputMethodManager) this.getSystemService(Context.INPUT_METHOD_SERVICE);
    inputManager.hideSoftInputFromWindow(this.getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
}

用try-catch包围它，这样键盘就已经关闭，应用程序就不会崩溃：

try{

View view = this.getCurrentFocus();
if (view != null) {  
    InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
}
}catch (Exception e)
{
  e.printStackTrace();
}