showSoftInput根本不为我工作。

我想我需要设置输入模式:(这里在manifest中的Activity组件中)

android:windowSoftInputMode="stateVisible" 

这很疯狂，但确实有效

fun showKeyboard(view: View) {
    try {
        InputMethodManager::class.java.getMethod(
                "showSoftInputUnchecked",
                Int::class.javaPrimitiveType,
                ResultReceiver::class.java
        ).apply {
            isAccessible = true
            invoke(view.context.inputMethodManager, 0, null)
        }
    }
    catch (e: Exception) {
       e.printStackTrace()
    }
}

有时劳科德鲁格的答案并不管用。我是这样做的，经过了一些尝试和错误:

public static void showKeyboard(Activity activity) {
    if (activity != null) {
        activity.getWindow()
                .setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
    }
}

public static void hideKeyboard(Activity activity) {
    if (activity != null) {
        activity.getWindow()
                .setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
    }
}

EditText部分:

    editText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (!hasFocus) {
                hideKeyboard(getActivity());
            } else {
                showKeyboard(getActivity());
            }
        }
    });

根据这个答案，我使用了setSoftInputMode方法，并覆盖了DialogFragment中的这些方法:

@Override
public void onCancel(@NonNull DialogInterface dialog) {
    super.onCancel(dialog);
    requireDialog().getWindow().setSoftInputMode(InputMethodManager.HIDE_IMPLICIT_ONLY);
}

@Override
public void onStart() {
    super.onStart();
    requireDialog().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
}

@Override
public void onStop() {
    super.onStop();
    requireDialog().getWindow().setSoftInputMode(InputMethodManager.HIDE_IMPLICIT_ONLY);
}

我也用这些方法创建了我自己的DialogFragment子类，所以当你创建另一个对话框并从这个类继承时，你会自动显示软键盘，而不需要任何其他编辑。希望对别人有用。

editText.post(new Runnable() {
    @Override
    public void run() {
        InputMethodManager imm = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.showSoftInput(editText, InputMethodManager.SHOW_IMPLICIT);
    }
});

以下是我从Square得到的一个更可靠的解决方案:

fun View.focusAndShowKeyboard() { /** * This is to be called when the window already has focus. */ fun View.showTheKeyboardNow() { if (isFocused) { post { // We still post the call, just in case we are being notified of the windows focus // but InputMethodManager didn't get properly setup yet. val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager imm.showSoftInput(this, InputMethodManager.SHOW_IMPLICIT) } } } requestFocus() if (hasWindowFocus()) { // No need to wait for the window to get focus. showTheKeyboardNow() } else { // We need to wait until the window gets focus. viewTreeObserver.addOnWindowFocusChangeListener( object : ViewTreeObserver.OnWindowFocusChangeListener { override fun onWindowFocusChanged(hasFocus: Boolean) { // This notification will arrive just before the InputMethodManager gets set up. if (hasFocus) { this@focusAndShowKeyboard.showTheKeyboardNow() // It’s very important to remove this listener once we are done. viewTreeObserver.removeOnWindowFocusChangeListener(this) } } }) } }

代码从这里开始。