Sending Data from Alert Dialog to New Activity-CodePudding

I am new to Android development and I am trying to send data via EditText to TextView from an alert dialog inflated in the MainActivity to a different activity (NewGame.java). I have tried intent.putExtra (see below) however I am getting null pointer exceptions as it seems I cannot access the views from the dialog layout xml file.

I know there are a few other ways to create an alert dialog so perhaps this way is not best for what i am trying to achieve?

MainActivity.java

public class MainActivity extends AppCompatActivity {

    Button newGame, prevGames, newSquad, savedSquads;

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

        newGame = findViewById(R.id.buttonNewGame);
        newGame.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                LayoutInflater inflater= getLayoutInflater();
                builder.setView(R.layout.new_game_dialog);
                final View myView= inflater.inflate(R.layout.new_game_dialog, null);

                EditText enterTeam1, enterTeam2, enterDate, enterTime, enterLocation;
                enterTeam1 = myView.findViewById(R.id.etTeam1);
                enterTeam2 = myView.findViewById(R.id.etTeam2);
                enterDate = myView.findViewById(R.id.etDate);
                enterTime = myView.findViewById(R.id.etTime);
                enterLocation = myView.findViewById(R.id.etLocation);

                builder.setTitle("New Game")
                        .setCancelable(true)
                        .setPositiveButton("Start", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialogInterface, int i) {
                                Intent intent = new Intent(MainActivity.this, NewGame.class);
                                intent.putExtra("TEAM1", enterTeam1.getText().toString());
                                intent.putExtra("TEAM2", enterTeam2.getText().toString());
                                intent.putExtra("DATE", enterDate.getText().toString());
                                intent.putExtra("TIME", enterTime.getText().toString());
                                intent.putExtra("LOCATION", enterLocation.getText().toString());
                                startActivity(intent);
                            }
                        })
                        .setNegativeButton("Cancel", null);

                builder.create();
                builder.show();
            }
        });

NewGame.java

public class NewGame extends AppCompatActivity {

   TextView team1, team2, date, time, location;


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

       team1 = findViewById(R.id.tvTeam1);
       team2 = findViewById(R.id.tvTeam2);
       date = findViewById(R.id.tvDate);
       time = findViewById(R.id.tvTime);
       location = findViewById(R.id.tvLocation);

       team1.setText(getIntent().getStringExtra("TEAM1"));
       team2.setText(getIntent().getStringExtra("TEAM2"));
       date.setText(getIntent().getStringExtra("DATE"));
       time.setText(getIntent().getStringExtra("TIME"));
       location.setText(getIntent().getStringExtra("LOCATION"));

   }
}

dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:orientation="vertical"
   android:paddingLeft="20dp"
   android:paddingRight="20dp"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content">


   <TextView
       android:id="@ id/tvNewGame"
       android:textAlignment="center"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="New Game"
       android:textColor="@color/black"
       android:textSize="30dp" />

   <EditText
       android:id="@ id/etTeam1"
       android:layout_width="211dp"
       android:layout_height="53dp"
       android:ems="10"
       android:hint="Team 1"
       android:inputType="textPersonName" />

   <EditText
       android:id="@ id/etTeam2"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:hint="Team 2"
       android:inputType="textPersonName"/>


   <EditText
       android:id="@ id/etDate"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:hint="Date"
       android:inputType="date" />

   <EditText
       android:id="@ id/etTime"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:hint="Time"
       android:inputType="textPersonName" />


   <EditText
       android:id="@ id/etLocation"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:hint="Location"
       android:inputType="textPersonName"/>

</LinearLayout>

activity_new_game.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".NewGame">

<TextView
       android:id="@ id/tvTime"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:text="time"
       app:layout_constraintBottom_toBottomOf="parent"
       app:layout_constraintEnd_toEndOf="parent"
       app:layout_constraintHorizontal_bias="0.502"
       app:layout_constraintStart_toStartOf="parent"
       app:layout_constraintTop_toTopOf="parent" />

   <TextView
       android:id="@ id/tvNewGame"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="New Game"
       android:textColor="@color/black"
       android:textSize="30dp"
       app:layout_constraintBottom_toBottomOf="parent"
       app:layout_constraintEnd_toEndOf="parent"
       app:layout_constraintStart_toStartOf="parent"
       app:layout_constraintTop_toTopOf="parent"
       app:layout_constraintVertical_bias="0.085" />

   <TextView
       android:id="@ id/tvTeam1"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:ems="10"
       android:text="team1"
       app:layout_constraintBottom_toBottomOf="parent"
       app:layout_constraintEnd_toEndOf="parent"
       app:layout_constraintHorizontal_bias="0.502"
       app:layout_constraintStart_toStartOf="parent"
       app:layout_constraintTop_toTopOf="parent"
       app:layout_constraintVertical_bias="0.192" />

</androidx.constraintlayout.widget.ConstraintLayout>

CodePudding user response：

I believe you are having this problem because you are actually inflating 2 views. And referencing the wrong one when you use findById.

            LayoutInflater inflater= getLayoutInflater();
            builder.setView(R.layout.new_game_dialog);
            final View myView= inflater.inflate(R.layout.new_game_dialog, null);

should look like this

            LayoutInflater inflater= getLayoutInflater();
            final View myView= inflater.inflate(R.layout.new_game_dialog, null);
            builder.setView(myView);