A화면에서 B화면으로 특정 버튼을 눌렀을때 이동하는 법(Intent)

main_XML

 

<EditText
    android:id="@+id/et_test"
    android:layout_width="200dp"
    android:layout_height="wrap_content"/>

<Button
    android:id="@+id/btn_move"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="이동" />

sub_XML

 

<TextView
    android:id="@+id/tv_sub"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="30sp"
    android:text="서브 액티비티 도착"/>

main_Activity

package com.shb.mycalculator;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

private Button btn_move;
private EditText et_test;
private String str;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    et_test = findViewById(R.id.et_test);


    btn_move = findViewById(R.id.btn_move);
    btn_move.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            str = et_test.getText().toString();
            Intent intent = new Intent(MainActivity.this, subActivity2.class);
            intent.putExtra("str",str);
            startActivity(intent); //액티비티 이동.
        }
    });
}

}

sub_Activity

package com.shb.mycalculator;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class subActivity2 extends AppCompatActivity {

private TextView tv_sub;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sub2);

    tv_sub = findViewById(R.id.tv_sub);

    Intent intent = getIntent();
    String str = intent.getStringExtra("str");

    tv_sub.setText(str);
}

}