把这个放到onResume()方法中。

binding.etxtSearch.isFocusableInTouchMode = true
binding.etxtSearch.isFocusable = true
binding.etxtSearch.requestFocus() 
val inputMethodManager = context?.getSystemService(Activity.INPUT_METHOD_SERVICE) as InputMethodManager
inputMethodManager.showSoftInput(binding.etxtSearch, InputMethodManager.SHOW_IMPLICIT)

final EditText tb = new EditText(this);
tb.requestFocus();
tb.postDelayed(new Runnable() {
    @Override
    public void run() {
        InputMethodManager inputMethodManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
        inputMethodManager.showSoftInput(tb, InputMethodManager.SHOW_IMPLICIT);
    }
}, 1000);

我最终找到了一个解决方案，并为它创建了一个Kotlin类

object KeyboardUtils {

    fun showKeyboard(editText: EditText) {
        editText.requestFocus()
        val imm = editText.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.showSoftInput(editText, 0)
    }

    fun hideKeyboard(editText: EditText) {
        val imm = editText.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.hideSoftInputFromWindow(editText.windowToken, 0)
    }

}

这里是KeyboardHelper类，用于隐藏和显示键盘

import android.content.Context;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;

/**
 * Created by khanhamza on 06-Mar-17.
 */

public class KeyboardHelper {
public static void hideSoftKeyboard(final Context context, final View view) {
    if (context == null) {
        return;
    }
    view.requestFocus();
    view.postDelayed(new Runnable() {
        @Override
        public void run() {
            InputMethodManager imm = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
assert imm != null;
imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
}
}, 1000);
}

public static void hideSoftKeyboard(final Context context, final EditText editText) {
    editText.requestFocus();
    editText.postDelayed(new Runnable() {
        @Override
        public void run() {
            InputMethodManager imm = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
assert imm != null;
imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);
}
}, 1000);
}


public static void openSoftKeyboard(final Context context, final EditText editText) {
    editText.requestFocus();
    editText.postDelayed(new Runnable() {
        @Override
        public void run() {
            InputMethodManager imm = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
assert imm != null;
imm.showSoftInput(editText, InputMethodManager.SHOW_IMPLICIT);
}
}, 1000);
}
}

我尝试了很多方法，但它不起作用，不确定是因为我使用共享过渡从片段到包含编辑文本的活动。

顺便说一句，我的编辑文本也包装在线性布局。

我添加了一个轻微的延迟来请求焦点，下面的代码对我来说是有效的: (芬兰湾的科特林)

 et_search.postDelayed({
     editText.requestFocus()

     showKeyboard()
 },400) //only 400 is working fine, even 300 / 350, the cursor is not showing

showKeyboard ()

 val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
 imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0)

在“OnCreate”中将光标移动到输入字段，但键盘不会打开:

window().setSoftInputMode(
    WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN
)
editText.requestFocus()

之后，当用户输入文本时:

val imm = editText.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
window.setSoftInputMode(
    WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE
)
imm.showSoftInput(editText, 0)

将充分工作，键盘将在需要时打开，而不设置时间延迟。 记住，输入文本后，你必须:

window.setSoftInputMode(
WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN
)
requestFocus()