我在 Activity2 和 ActivityMain 之間傳遞數據時遇到問題。我有一個帶有“添加人員”按鈕的 ActivityMain。當我按下此按鈕時，我會轉到 Activity2，然后我填寫字段名稱并按下按鈕“添加”，但無法在我的 ActivityMain 上添加名稱。ActivityMain.xml<?xml version="1.0" encoding="utf-8"?><android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"android:padding="5dp"tools:context=".MainActivity"><LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"><Button    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:text="Add Person"    android:onClick="addPerson"   /></LinearLayout></android.support.constraint.ConstraintLayout>ActivityMain.javapackage com.example.test.zadanie01;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View; import android.widget.TextView;public class MainActivity extends AppCompatActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);}protected void onActivityResult(int requestCode, int resultCode, Intent data){        Intent intent = getIntent();        String message = intent.getStringExtra(PersonActivity.EXTRA_MESSAGE);        TextView textView = new TextView(this);        textView.setTextSize(40);        textView.setText(message);        setContentView(textView);}public void addPerson(View view){    Intent intent = new Intent(this, PersonActivity.class);    startActivityForResult(intent, 1);}}