Many times in android applications we have to pass data from one activity to another for performing some operations. There are several different ways that are used to give data from one activity to another activity. In this article, we will specifically take a look at How to use putExtra() and getExtra() for passing and retrieving string data in the android application.
Note: This Android article covers in both Java and Kotlin languages.
Step by Step Implementation
Step 1: Create a New Project in Android Studio
To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio.
Step 2: Working with the activity_main.xml file
Navigate to app > res > layout > activity_main.xml and add the below code to it. Comments are added in the code to get to know in detail.
XML
<?xml version="1.0" encoding="utf-8"?><RelativeLayout android:id="@+id/idRLContainer" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".MainActivity"> <!--on below line we are creating a text for our app--> <TextView android:id="@+id/idTVHeading" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_above="@id/idEdtMsg" android:layout_centerInParent="true" android:layout_margin="20dp" android:gravity="center" android:padding="10dp" android:text="Using putExtras() and getExtras() in Android" android:textAlignment="center" android:textColor="@color/black" android:textSize="20sp" android:textStyle="bold" /> <EditText android:id="@+id/idEdtMsg" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_above="@id/idBtnPassData" android:layout_margin="20dp" android:hint="Enter your message" /> <!--on below line we are creating a button--> <Button android:id="@+id/idBtnPassData" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerInParent="true" android:layout_margin="20dp" android:text="Pass Data" android:textAllCaps="false" /> </RelativeLayout> |
Step 3: Creating a new activity
Navigate to app>java>your app’s package name>Right click>New>Empty Activity and name it as MainActivity2 and click on finish to create a new activity.
Step 4: Working with the MainActivity file
Navigate to app > java > your app’s package name > MainActivity file and add the code below. Comments are added in the code to get to know in detail.
Kotlin
package com.gtappdevelopers.kotlingfgproject import android.content.Intentimport android.os.Bundleimport android.widget.Buttonimport android.widget.EditTextimport androidx.appcompat.app.AppCompatActivity class MainActivity : AppCompatActivity() { // on below line we are creating a variable. lateinit var msgEdt: EditText lateinit var passDataBtn: Button override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) // on below line we are initializing our variables. passDataBtn = findViewById(R.id.idBtnPassData) msgEdt = findViewById(R.id.idEdtMsg) // on below line we are adding // click listener for our button passDataBtn.setOnClickListener { // on below line we are getting // data from edit text val msg = msgEdt.text.toString() // on below line we are creating a new // intent to open a new activity. val i = Intent(this@MainActivity, MainActivity2::class.java) // on below line we are passing // data to our new activity. i.putExtra("message", msg) // on below line we are // starting a new activity. startActivity(i) } }} |
Java
package com.gtappdevelopers.kotlingfgproject; import android.content.Intent;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.EditText; import androidx.appcompat.app.AppCompatActivity; public class MainActivity extends AppCompatActivity { // on below line we are creating a variable. private Button passDataBtn; private EditText msgEdt; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // on below line we are initializing variables with ids. passDataBtn = findViewById(R.id.idBtnPassData); msgEdt = findViewById(R.id.idEdtMsg); // on below line we are adding click listener for our button passDataBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // on below line we are getting data from edit text String msg = msgEdt.getText().toString(); // on the below line we are creating a new // intent to open a new activity. Intent i = new Intent(MainActivity.this, MainActivity2.class); // on below line we are passing // data to our new activity. i.putExtra("message", msg); // on below line we are // starting a new activity. startActivity(i); } }); }} |
Step 5: Working with the activity_main2.xml file
Navigate to app>res>layout>activity_main2.xml and add the below code to it. Comments are added in the code to get to know in detail.
XML
<?xml version="1.0" encoding="utf-8"?><RelativeLayout android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity2"> <!--on below line we are creating a text for our app--> <TextView android:id="@+id/idTVMsg" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_centerInParent="true" android:layout_margin="20dp" android:gravity="center" android:padding="10dp" android:text="Message" android:textAlignment="center" android:textColor="@color/black" android:textSize="20sp" android:textStyle="bold" /> </RelativeLayout> |
Step 6: Working with the MainActivity2 file
Navigate to app > java > your app’s package name > MainActivity2 file and add the code below. Comments are added in the code to get to know in detail.
Kotlin
package com.gtappdevelopers.kotlingfgproject import android.os.Bundleimport android.widget.TextViewimport androidx.appcompat.app.AppCompatActivity class MainActivity2 : AppCompatActivity() { // on the below line we are creating a variable. lateinit var msgTV: TextView override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main2) // on below line we are initializing our variable. msgTV = findViewById(R.id.idTVMsg) // on below line we are setting our message to our text view. msgTV.text = intent.extras?.getString("message") ?: "No message found" }} |
Java
package com.gtappdevelopers.kotlingfgproject; import android.os.Bundle;import android.widget.TextView;import androidx.appcompat.app.AppCompatActivity; public class MainActivity2 extends AppCompatActivity { // on the below line we are creating a variable. private TextView msgTV; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // on below line we are initializing variables with ids. msgTV = findViewById(R.id.idTVMsg); // on below line we are setting our message to our text view. msgTV.setText(getIntent().getStringExtra("message")); }} |
Now run your application to see the output of it.
Output:
