覆盖对话框片段中的onActivityCreated，并将getDialog().getWindow().setSoftInputMode(LayoutParams.SOFT_INPUT_STATE_VISIBLE);放入其中

tyczj的答案对我不起作用。
解决方案是在onCreateDialog中

Dialog d = builder.create();
d.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
return d;

最后，代码将是这样的

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    // Inflate and set the layout for the dialog
    // Pass null as the parent view because its going in the dialog layout
    builder
           .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int id) {
                    callback.onYesConnectClick(edit.getText().toString());
                }
            })
            .setNegativeButton(R.string.refuse, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int id) {
                    callback.onNoConnectClick();
                }
            });

    Dialog d = builder.create();
        d.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
return d;
}

在onActivityCreated或onCreateDialog方法中使用"SOFT_INPUT_STATE_ALWAYS_VISIBLE"而不是"SOFT_INPUT_STATE_VISIBLE"。

如果使用setLayout()调用，请注意它。我花了一段时间才意识到它可能会覆盖窗口的属性。在将其 Package 成处理程序后，接受的解决方案对我有效。

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    final Dialog dialog = super.onCreateDialog(savedInstanceState);
    dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE);

    return dialog;
}

@Override
public void onStart() {
    super.onStart();

    // without a handler, the window sizes itself correctly
    // but the keyboard does not show up
    new Handler().post(new Runnable() {
        @Override
        public void run() {
            getDialog().getWindow().setLayout(DIALOG_WIDTH, DIALOG_HEIGHT);
        }
    });
}

如果你想在短暂的延迟后显示键盘，你应该使用另一种方法。使用onActivityCreated和onCreateDialog的解决方案工作正常，但用于即时键盘显示。如果你有EditText，你应该在它上面打开键盘，而不是在一个对话框上。图片来源：https://stackoverflow.com/a/65007148/2914140

fun showKeyboard(view: EditText) {
    val imm = view.context.getSystemService(
        Context.INPUT_METHOD_SERVICE) as InputMethodManager?
    imm?.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT)
}

override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
    super.onCreateDialog(savedInstanceState)

    val view = activity?.layoutInflater?.inflate(R.layout.your_layout, null)

    view?.edit_text?.run {
        requestFocus() // Required for showing a keyboard.
        setText("Some text")
        setSelection(text.length)
    }

    val dialogBuilder = MaterialAlertDialogBuilder(requireContext()).apply {
        setView(view)
        // Set message, buttons.
        setCancelable(false)
    }
    val dialog = dialogBuilder.create()

    Handler(Looper.getMainLooper()).postDelayed({
        view?.edit_text?.let { showKeyboard(it) }
    }, 100)
//    Instead of Handler you can use coroutines:
//    lifecycleScope.launch {
//        delay(100)
//        view?.edit_text?.let { showKeyboard(it) }
//    }

    return dialog
}

出于某种原因，沿着onCreateView中的myEditText.requestFocus()之外，没有任何东西对我有用：

override fun onStart() {
    dialog?.window?.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE)
    super.onStart()
}