我创建了很好的kotlin-esqe扩展函数，如果有人感兴趣的话

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

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

这对我很有用。我为对话框设置了一个OnShowListener，在那个监听器中，我为文本字段设置了一个onFocusChangeListener，在那个FocusChangeListener中，我用100ms的延迟调用showSoftInput，然后删除FocusChangeListener，所以它只处理第一个焦点变化。

当调用dialog.show()时，OnShowListener被调用，它请求文本字段的焦点。当文本字段获得焦点时，将调用FocusChangeListener并最终显示键盘。

    val views = DialogBinding.inflate(layoutInflater) // layout with 'textfield'
    val dialog = MaterialAlertDialogBuilder(requireContext())
        .setTitle("Exercise")
        .setView(views.root)
        ...
        .create()
    dialog.setOnShowListener {
        views.textfield.onFocusChangeListener = View.OnFocusChangeListener { view, _ ->
            view.postDelayed({
                (view.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager).showSoftInput(view, 0)
            }, 100)                
            views.textfield.onFocusChangeListener = null
        }
        views.repcount.requestFocus()
    }
    dialog.show()

好吧，这是一个相当老的帖子，仍然有一些东西需要添加。这是两个简单的方法，帮助我保持键盘在控制之下，他们工作得非常完美:

显示键盘

public void showKeyboard() {
    InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
    View v = getCurrentFocus();
    if (v != null)
        imm.showSoftInput(v, 0);
}

隐藏键盘

public void hideKeyboard() {
    InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
    View v = getCurrentFocus();
    if (v != null)
        imm.hideSoftInputFromWindow(v.getWindowToken(), 0);
}

是的，你可以用setOnFocusChangeListener来做，它会帮助你。

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);
        }
    }
});

试试这个

SomeUtils.java showKeyboard(Activity Activity, boolean show) { InputMethodManager = (InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE); 如果(显示) inputMethodManager.toggleSoftInput (InputMethodManager.SHOW_FORCED 0); 其他的 inputMethodManager.toggleSoftInput (InputMethodManager.HIDE_IMPLICIT_ONLY 0); ｝

edittext.setShowSoftInputOnFocus(真正的);是关于这个问题的最流畅的解决方案。

AlertDialog.Builder alertSearch = new AlertDialog.Builder(activity);
alertSearch.setIcon(R.drawable.ic_launcher);
alertSearch.setTitle("Search");
final EditText edittext = new EditText(activity);
edittext.setSingleLine();
edittext.setHint("...");
edittext.setText(SearchString);

在聚焦时设置键盘

edittext.setShowSoftInputOnFocus(true);

获得焦点

edittext.requestFocus();

And

alertSearch.setView(edittext);
alertSearch.setPositiveButton("OK", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int whichButton) {
        // Do something
        act.recreate();
    }
});
alertSearch.show();