将这些方法放在Util类中，并在任何地方使用。

科特林

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

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

Java

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

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

看看这个手动隐藏和显示IME的讨论。然而，我的感觉是，如果一个集中的EditText没有带来IME，这是因为你正在调用AlertDialog.show()在你的OnCreate()或一些其他方法，在屏幕实际呈现之前被唤起。移动到OnPostResume()应该在这种情况下修复它，我相信。

您可以在AlertDialog的EditText上创建一个焦点侦听器，然后获取AlertDialog的窗口。从那里你可以通过调用setSoftInputMode来显示软键盘。

final AlertDialog dialog = ...;

editText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
    @Override
    public void onFocusChange(View v, boolean hasFocus) {
        if (hasFocus) {
            dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
        }
    }
});

最初的问题涉及对话框和我的EditText是常规视图。无论如何，我认为这对你们大多数人也适用。所以这是对我有效的方法(上面建议的最高评价的方法对我没有任何作用)。下面是一个自定义的EditView，它可以做到这一点(子类化不是必需的，但我发现这对我的目的很方便，因为我还想在视图可见时捕获焦点)。

This is actually largely the same as the tidbecks answer. I actually didn't notice his answer at all as it had zero up votes. Then I was about to just comment his post, but it would have been too long, so I ended doing this post anyways. tidbeck points out that he's unsure how it works with devices having keyboards. I can confirm that the behaviour seems to be exactly the same in either case. That being such that on portrait mode the software keyboard gets popped up and on landscape it doesn't. Having the physical keyboard slid out or not makes no difference on my phone.

因为，我个人觉得行为有点尴尬，我选择使用:InputMethodManager.SHOW_FORCED。这是我想要的效果。无论朝向如何，键盘都是可见的，然而，至少在我的设备上，如果硬件键盘已经滑出，它不会弹出。

import android.app.Service;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;

public class BringOutTheSoftInputOnFocusEditTextView extends EditText {

    protected InputMethodManager inputMethodManager;

    public BringOutTheSoftInputOnFocusEditTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    public BringOutTheSoftInputOnFocusEditTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public BringOutTheSoftInputOnFocusEditTextView(Context context) {
        super(context);
        init();
    }

    private void init() {
        this.inputMethodManager = (InputMethodManager)getContext().getSystemService(Service.INPUT_METHOD_SERVICE);
        this.setOnFocusChangeListener(new View.OnFocusChangeListener() {
            @Override
            public void onFocusChange(View v, boolean hasFocus) {
                if (hasFocus) {
                    BringOutTheSoftInputOnFocusEditTextView.this.inputMethodManager.showSoftInput(BringOutTheSoftInputOnFocusEditTextView.this, InputMethodManager.SHOW_FORCED);
                }
            }
        });
    }

    @Override
    protected void onVisibilityChanged(View changedView, int visibility) {
        super.onVisibilityChanged(changedView, visibility);
        if (visibility == View.VISIBLE) {
            BringOutTheSoftInputOnFocusEditTextView.this.requestFocus();
        }
    }

}

要显示键盘，对我来说，我必须执行以下操作

Android文本字段:设置焦点+软输入编程

基本上解决方案如下

@Override
public void onResume() {
    super.onResume();
    //passwordInput.requestFocus(); <-- that doesn't work
    passwordInput.postDelayed(new ShowKeyboard(), 325); //250 sometimes doesn't run if returning from LockScreen
}

ShowKeyboard在哪里

private class ShowKeyboard implements Runnable {
    @Override
    public void run() {
        passwordInput.setFocusableInTouchMode(true);
        //passwordInput.requestFocusFromTouch(); //this gives touch event to launcher in background -_-
        passwordInput.requestFocus();
        getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
        ((InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE)).showSoftInput(passwordInput, 0);
    }
}

在成功输入之后，我还确保隐藏了键盘

getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);
((InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE))
                    .hideSoftInputFromWindow(getView().getWindowToken(), 0);

我们可以在对话显示时默认打开键盘

dialog.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM)
dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE)