part 26 - Activity Lifecycle

MainActivity.java

package first.learn.listviewproject;

import static first.learn.listviewproject.MainActivity2.Message;

import androidx.appcompat.app.AppCompatActivity;

import android.app.AlertDialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {


    Button btnOne, btnTwo;
    TextView tvOne;
    /*
   Activity Starting  :
    */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        setTitle("Screen One ");

        btnOne = (Button)findViewById(R.id.btnOne);
        tvOne = (TextView)findViewById(R.id.tvOne);
        btnTwo = (Button)findViewById(R.id.btnTwo);

        btnOne.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                startActivity(new Intent(MainActivity.this, MainActivity2.class));
            }
        });


        btnTwo.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                new AlertDialog.Builder(MainActivity.this)
                        .setTitle("Alert ")
                        .setMessage("yes ")
                        .setPositiveButton("Ok", null)
                        .create().show();
            }
        });

        System.out.println("Calling Method : Oncreate - Activity 1");

    }
   @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);

        System.out.println("Calling Method : onWindowFocusChanged - Activity 1");
    }
    @Override
    protected void onStart() {
        super.onStart();

        System.out.println("Calling Method : OnStart - Activity 1");

    }



    @Override
    protected void onResume() {
        super.onResume();
        System.out.println("Calling Method : OnResume - Activity 1 ");
        tvOne.setText(Message);
    }


    /*
    Activity Closing :
     */

    @Override
    protected void onPause() {
        super.onPause();
        System.out.println("Calling Method : onPause - Activity 1");
    }


    @Override
    protected void onStop() {
        super.onStop();
        System.out.println("Calling Method : onStop - Activity 1");
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        System.out.println("Calling Method : onDestroy - Activity 1");
    }
}

 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    tools:context=".MainActivity"
    android:orientation="vertical"
    android:layout_margin="16dp">


    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/btnOne"
        android:text="Next Activity 2"/>


    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/btnTwo"
        android:text="Show Alert"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="25dp"
        android:id="@+id/tvOne"
        />

</LinearLayout>

ActivityMain2.Java

package first.learn.listviewproject;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.Handler;
import android.widget.EditText;

public class MainActivity2 extends AppCompatActivity {


    public  static String  Message = "";

    EditText etOne;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        setTitle("Screen 2");

        etOne = (EditText)findViewById(R.id.etOne);
        System.out.println("Calling Method : OnCreate - Activity 2");


        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {

                System.out.println("Calling Method : Post Delayed - Activity 2");

            }
        },500);

    }

    @Override
    protected void onStart() {
        super.onStart();
        System.out.println("Calling Method : OnStart - Activity 2");

    }

    @Override
    protected void onResume() {
        super.onResume();
        System.out.println("Calling Method : OnResume - Activity 2");
    }


    /*
    Activity Closing :
     */

    @Override
    protected void onPause() {
        super.onPause();
        System.out.println("Calling Method : onPause - Activity 2");
    }


    @Override
    protected void onStop() {
        super.onStop();
        System.out.println("Calling Method : onStop - Activity 2");
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        System.out.println("Calling Method : onDestroy - Activity 2");
    }

    @Override
    public void onBackPressed() {


        String s = etOne.getText().toString();

        Message = s ;



        super.onBackPressed();
    }
}

Activity_main2.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    tools:context=".MainActivity2"
    android:orientation="vertical"
    android:layout_margin="16dp">


    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/etOne"
        android:hint="Write"
        android:inputType="number"/>


</LinearLayout>