Button Click Open Gmail app and send email android java example

1/  Manifest Internet permission .

<uses-permission android:name="android.permission.INTERNET"/>

2/  XML Desing .

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"

    >

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Email_Send"
        android:gravity="center"
        android:textSize="30dp"
        android:textColor="@color/black"
        android:layout_above="@+id/layout"
        android:layout_marginBottom="30dp"
        android:textStyle="bold"

        />

    <LinearLayout
        android:id="@+id/layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"

        >

        <EditText
            android:id="@+id/edSubject"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:padding="5dp"
            android:hint="Enter your subject"
            android:layout_marginTop="0dp"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:textColor="@color/black"

            />

        <EditText
            android:id="@+id/edContent"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:padding="5dp"
            android:hint="Enter your Content"
            android:layout_marginTop="10dp"
            android:layout_marginLeft="10dp"
            android:textColor="@color/black"
            android:layout_marginRight="10dp"
            android:inputType=""

            />

        <EditText
            android:id="@+id/edEmail"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:padding="5dp"
            android:hint="Enter your Email"
            android:layout_marginTop="10dp"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:textColor="@color/black"
            android:inputType="textEmailAddress"

            />

        <Button
            android:id="@+id/button"
            android:layout_width="150dp"
            android:layout_height="wrap_content"
            android:text="Send"
            android:textColor="@color/white"
            android:layout_gravity="center"
            android:layout_marginTop="20dp"
            android:textSize="25sp"
          

            />

    </LinearLayout>

</RelativeLayout>

3/  MainActivity.

package com.tutorialb.buttonclickopengmailappandsendemail;

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

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

public class MainActivity extends AppCompatActivity {

    Button button;
    EditText edSubject;
    EditText edContent;
    EditText edEmail;

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


        button=findViewById(R.id.button);
        edSubject=findViewById(R.id.edSubject);
        edContent=findViewById(R.id.edContent);
        edEmail=findViewById(R.id.edEmail);

        final String[] subject = new String[1];
        final String[] content = new String[1];
        final String[] email = new String[1];

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                subject[0] =edSubject.getText().toString();
                content[0] =edContent.getText().toString();
                email[0] =edEmail.getText().toString();

                if (subject[0].equals("") && content[0].equals("") && email[0].equals("")){
                    Toast.makeText(MainActivity.this, "all fields are required", Toast.LENGTH_SHORT).show();
                }else {
                    Mail_send(subject[0], content[0], email[0]);
                    Toast.makeText(MainActivity.this, "Email_send", Toast.LENGTH_SHORT).show();
                }
            }
        });

    }




    public void Mail_send (String subject, String content, String email){

        Intent intent=new Intent(Intent.ACTION_SEND);
        intent.putExtra(Intent.EXTRA_EMAIL,new String[]{email});
        intent.putExtra(Intent.EXTRA_SUBJECT, (CharSequence) subject);
        intent.putExtra(Intent.EXTRA_TEXT, content);
        intent.setType("Massage/rfc822");
        startActivity(Intent.createChooser(intent,"Choose email client : "));

    }
}