Passare dati da Activity a Fragment

In questo esempio andiamo a passare dati da un Activity a un Fragment
Per specificare che la transazione include la modifica del frammento con la navigazione dello stack andiamo a chiamare il metodo FragmentTransaction.addToBackStack(). Quindi sarà possibile tornare indietro premendo il pulsante stack:

Activity_main.xml

<?xml version=”1.0″ encoding=”utf-8″?>
<LinearLayout
xmlns:android=”http://schemas.android.com/apk/res/android“
android:layout_width=”match_parent”
android:layout_height=”match_parent”
android:gravity=”center”
android:orientation=”vertical”>

<EditText
android:id=”@+id/edt”
android:layout_width=”match_parent”
android:layout_height=”60dp”

android:hint=”Enter Name”
android:layout_marginTop=”20dp”/>

<Button
android:id=”@+id/button”
android:layout_width=”200dp”
android:layout_height=”50dp”
android:text=”Pass Data”

android:layout_gravity=”center” />

<FrameLayout
android:id=”@+id/frameLayout”
android:layout_width=”match_parent”
android:layout_height=”match_parent” />

</LinearLayout>

Fragment_1.xml

<LinearLayout xmlns:android=”http://schemas.android.com/apk/res/android“
    android:layout_width=”fill_parent”
    android:layout_height=”fill_parent”
    android:orientation=”vertical”>
    <TextView
android:id=”@+id/get_name”
android:layout_width=”wrap_content”
android:layout_height=”wrap_content”

android:textSize=”30sp”/>
</LinearLayout>

Fragnent1.java

package com.example.passData.activities;
import android.app.*;
import android.widget.*;
import android.view.*;
import com.example.passData.*;
import android.os.*;

public class Fragment1 extends Fragment
{

String name;

public fragment1(String name) {
this.name = name;
}

  @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  View view = inflater.inflate(R.layout.fragment_1, container, false);

  TextView myName = view.findViewById(R.id.get_name);
  myName.setText(name);

return view;
}
}

MainActivity.java
package com.example.passData.activities;

import android.app.Activity;
import android.os.Bundle;
import com.example.passData.R;
import android.widget.*;
import android.view.*;
import android.app.*;

public class MainActivity extends Activity {
Button btn;
EditText userName;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

btn=findViewById(R.id.button);
userName = findViewById(R.id.edt);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String name=userName.getText().toString();

FragmentTransaction transaction=getFragmentManager() .beginTransaction();

transaction.addToBackStack(name);
transaction.replace(R.id.frameLayout,new Fragment1 (name)).commit();
}
} );

}
}