How to send data to previous activity in Android?

This example demonstrate about How to send data to previous activity in Android

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version = "1.0" encoding = "utf-8"?>
<RelativeLayout xmlns:android = "https://schemas.android.com/apk/res/android"
   xmlns:tools = "https://schemas.android.com/tools"
   android:layout_width = "match_parent"
   android:layout_height = "match_parent"
   android:layout_margin = "16dp"
   android:orientation = "vertical"
   tools:context = ".MainActivity">
   <TextView
      android:id = "@+id/text_view"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content"
      android:layout_centerInParent = "true"
      android:layout_gravity = "center" />
   <Button
      android:id = "@+id/button"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content"
      android:layout_alignParentBottom = "true"
      android:layout_gravity = "center"
      android:layout_marginTop = "16dp"
      android:text = "Get Data" />
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.java

package com.example.myapplication;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
   private final static int MY_REQUEST_CODE = 1;
   TextView textView;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      textView = findViewById(R.id.text_view);
      Button button = findViewById(R.id.button);
      button.setOnClickListener(new View.OnClickListener() {
         @Override
         public void onClick(View v) {
            Intent intent = new Intent(MainActivity.this, SecondActivity.class);
            startActivityForResult(intent, MY_REQUEST_CODE);
         }
      });
   }
   @Override
   protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
      super.onActivityResult(requestCode, resultCode, data);
      if (resultCode = = Activity.RESULT_OK) {
         if (requestCode = = MY_REQUEST_CODE) {
            if (data ! = null)
            textView.setText(data.getStringExtra("value"));
         }
      }
   }
}

Step 4 − Add the following code to res/layout/activity_second.xml.

<?xml version = "1.0" encoding = "utf-8"?>
<RelativeLayout xmlns:android = "https://schemas.android.com/apk/res/android"
   xmlns:tools = "https://schemas.android.com/tools"
   android:layout_width = "match_parent"
   android:layout_height = "match_parent"
   android:layout_margin = "16dp"
   android:orientation = "vertical"
   tools:context = ".SecondActivity">
   <EditText
      android:id = "@+id/edit_text"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content"
      android:layout_centerInParent = "true"
      android:layout_gravity = "center"
      android:hint = "Enter something to return previous activity"
      android:inputType = "text" />
   <Button
      android:id = "@+id/button"
      android:layout_width = "match_parent"
      android:layout_height = "wrap_content"
      android:layout_alignParentBottom = "true"
      android:layout_gravity = "center"
      android:layout_marginTop = "16dp"
      android:text = "Done" />
</RelativeLayout>

Step 5 − Add the following code to src/SecondActivity.java

package com.example.myapplication;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class SecondActivity extends AppCompatActivity {
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_second);
      final EditText editText = findViewById(R.id.edit_text);
      Button button = findViewById(R.id.button);
      button.setOnClickListener(new View.OnClickListener() {
         @Override
         public void onClick(View v) {
            String value = editText.getText().toString().trim();
            Intent intent = new Intent();
            intent.putExtra("value", value);
            setResult(RESULT_OK, intent);
            finish();
         }
      });
   }
}

Step 6 − Add the following code to androidManifest.xml

<?xml version = "1.0" encoding = "utf-8"?>
<manifest xmlns:android = "https://schemas.android.com/apk/res/android"
   package = "com.example.myapplication">
   <application
      android:allowBackup = "true"
      android:icon = "@mipmap/ic_launcher"
      android:label = "@string/app_name"
      android:roundIcon = "@mipmap/ic_launcher_round"
      android:supportsRtl = "true"
      android:theme = "@style/AppTheme">
      <activity android:name = ".MainActivity">
         <intent-filter>
            <action android:name = "android.intent.action.MAIN" />
            <category android:name = "android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
      <activity android:name = ".SecondActivity"></activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click Run    icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –