Using a DialogFragment to create buttons

Question

I need to use a dialogfragment to create buttons each time the Start Goal button is pressed. The Dialogfragment contains 2 editTexts for a goal name and goal amount. How can I get the value of the 2 editTexts and display them on the button?

I used 2 text fields in the main activity to test if the dialog box can send the values of the 2 edit texts to the text fields on the main activity.

This is the xml for the activity_main

<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.eugene.myapplication.MainActivity">

<TextView
    android:id="@+id/textview_GoalName"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentStart="true"
    android:layout_centerVertical="true"
    android:gravity="center_horizontal"
    android:text="Here will be your Goal Name"
    android:textSize="30sp" />

<TextView
    android:id="@+id/textview_GoalAmount"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentStart="true"
    android:layout_below="@+id/textview_GoalName"
    android:gravity="center_horizontal"
    android:text="Here will be your Goal Amount"
    android:textSize="30sp" />

<Button
    android:id="@+id/button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textview_GoalAmount"
    android:layout_centerHorizontal="true"
    android:text="Create a Goal!" />

</RelativeLayout>

This is the xml for the dialogfragment

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="16dp">


<EditText
    android:id="@+id/edit_goalName"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="Goal Name"/>

<EditText
    android:id="@+id/edit_goalAmt"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentStart="true"
    android:layout_below="@+id/edit_goalName"
    android:hint="Goal Amount"
    android:inputType="number" />

This is the java code for the MainActivity

public class MainActivity extends AppCompatActivity implements 
ExampleDialog.ExampleDialogListener {

private TextView textViewGoalName;
private TextView textViewGoalAmt;
private Button button;

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

    textViewGoalName = findViewById(R.id.textview_GoalName);
    textViewGoalAmt = findViewById(R.id.textview_GoalAmount);
    button = findViewById(R.id.button);
    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            openDialog();
        }
    });
}


public void openDialog(){
    ExampleDialog exampleDialog = new ExampleDialog();
    exampleDialog.show(getSupportFragmentManager(), "example dialog");
}

@Override
public void applyTexts(String username, String password) {
    textViewGoalName.setText(username);
    textViewGoalAmt.setText(password);
  }
}

Here is the java code for the dialogframgent

public class ExampleDialog extends AppCompatDialogFragment {

private EditText editTextGoalName;
private EditText editTextGoalAmt;
private ExampleDialogListener listener;

@Override

public Dialog onCreateDialog(Bundle savedInstanceState) {
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

    LayoutInflater inflater =  getActivity().getLayoutInflater();
    View view = inflater.inflate(R.layout.layout_dialog,null);

    builder.setView(view)
            .setTitle("Create Goal")
            .setNegativeButton("Maybe next time..", new 
             DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, int i){

                }
            })
            .setPositiveButton("Start!", new 
             DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, int i){
                    String goalname = editTextGoalName.getText().toString();
                    String goalamt = editTextGoalAmt.getText().toString();
                    String message = "Fields Required";

                    if (goalname == "" && goalamt == ""){
                        Toast.makeText(getActivity(),message, 
                        Toast.LENGTH_SHORT).show();
                    }
                    listener.applyTexts(goalname, goalamt);
                }
            });

    editTextGoalName = view.findViewById(R.id.edit_goalName);
    editTextGoalAmt = view.findViewById(R.id.edit_goalAmt);

    return builder.create();
}

@Override
public void onAttach(Context context) {
    super.onAttach(context);

    try {
        listener = (ExampleDialogListener) context;
    } catch (ClassCastException e) {
        throw new ClassCastException(context.toString() + "Must implement 
        ExampleDialogListener");
    }
}

public interface ExampleDialogListener{
    void applyTexts(String username, String password);
    }
}

Answer 1

I recommend that using the interface. The interface can be used to communicate with activity and fragment.

You can check this in below link: https://developer.android.com/guide/components/fragments.html?hl=ko#CommunicatingWithActivity

Define an interface.

And implement it in your Activity.

Define an "interface" member variable in your DialogFragment.

And the member variable will be initialized in your "onAttach()" callback method.

The details code example you can find in upper link.