如何在Android Studio的ApplicationTest.java中编辑MainActivity的EditText字段？

// 导入所需的包
import android.widget.EditText;
import androidx.test.rule.ActivityTestRule;
import androidx.test.ext.junit.runners.AndroidJUnit4;
import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;
import static androidx.test.espresso.Espresso.onView;
import static androidx.test.espresso.action.ViewActions.clearText;
import static androidx.test.espresso.action.ViewActions.typeText;
import static androidx.test.espresso.matcher.ViewMatchers.withId;

@RunWith(AndroidJUnit4.class)
public class ApplicationTest {

    @Rule
    public ActivityTestRule<MainActivity> mActivityRule = new ActivityTestRule<>(MainActivity.class);

    @Test
    public void testEditText() {
        // 获取MainActivity的实例
        MainActivity activity = mActivityRule.getActivity();

        // 获取EditText字段的引用
        EditText editText = activity.findViewById(R.id.editText);

        // 编辑EditText字段
        editText.performClick(); // 模拟点击事件
        onView(withId(R.id.editText)).perform(clearText()); // 清空EditText
        onView(withId(R.id.editText)).perform(typeText("Hello, World!")); // 输入文本
    }
}