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Android DialogFragment Tutorial

View more Tutorials:

  1. Android DialogFragment
  2. Example of DialogFragment

1- Android DialogFragment

Android DialogFragment is a fragment containing a Dialog. It controls the operation of the Dialog, such as determines when to hide, display, or dismiss this Dialog. You should interact with the Dialog through the methods of DialogFragment instead of interacting directly.
You might ask the question: "Why do they need a DialogFragment when we already have a Dialog?". The answer is DialogFragment was created to overcome some of Dialog's weaknesses.

  • TODO

See more at:
It is easy for you to get a DialogFragment, just take 2 steps as follows:
Starting with writing a class of YourDialogFragment extended from the DialogFragment class. And then override the onCreateDialog(Bundle) method which returns a Dialog (YourDialog). As a result, YourDialogFragment now plays a role of a container of YourDialog.
Android DialogFragment Javadocs:

2- Example of DialogFragment

In this example, we are going to create a YesNoDialogFragment class extended from the DialogFragment class. This class contains an AlertDialog with 2 buttons, YES/NO.
This example will showcase how to create and display YesNoDialogFragment from an Activity. You can also create and display YesNoDialogFragment from one another fragment with a little change in the code.
Alright, now on Android Studio create a project:
  • File > New > New Project > Empty Activity
    • Name: DialogFragmentExample
    • Package name: org.o7planning.dialogfragmentexample
    • Language: Java
The application interface looks like this:
activity_main.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=".MainActivity">

    <Button
        android:id="@+id/button_show"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Show Dialog Fragment"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginTop="24dp"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        android:gravity="center"
        android:text="---"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button_show" />
</androidx.constraintlayout.widget.ConstraintLayout>
YesNoDialogFragment.java
package org.o7planning.dialogfragmentexample;

import android.app.Activity;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AlertDialog;
import androidx.fragment.app.DialogFragment;

public class YesNoDialogFragment extends DialogFragment {

    public static final String ARG_TITLE = "YesNoDialog.Title";
    public static final String ARG_MESSAGE = "YesNoDialog.Message";

    private YesNoDialogFragmentListener listener;

    public interface YesNoDialogFragmentListener {
        /**
         *
         * @param resultCode - Activity.RESULT_OK, Activity.RESULT_CANCEL
         * @param data
         */
         public void onYesNoResultDialog(int resultCode, @Nullable Intent data);
    }

    public YesNoDialogFragment() {

    }

    public void setOnYesNoDialogFragmentListener(YesNoDialogFragmentListener listener) {
        this.listener = listener;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        Bundle args = getArguments();
        String title = args.getString(ARG_TITLE);
        String message = args.getString(ARG_MESSAGE);

        return new AlertDialog.Builder(getActivity())
                .setTitle(title)
                .setMessage(message)
                .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        buttonOkClick();
                    }
                })
                .setNegativeButton("No", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        buttonNoClick();
                    }
                })
                .create();
    }

    private void buttonOkClick() {
        int resultCode = Activity.RESULT_OK;

        Bundle bundle = new Bundle();
        bundle.putString("key1", "Value 1");
        bundle.putString("key2", "Value 2");
        Intent data  = new Intent().putExtras(bundle);

        // Open this DialogFragment from an Activity.
        if(this.listener != null)  {
            this.listener.onYesNoResultDialog(Activity.RESULT_OK, data);
        }
        // Open this DialogFragment from another Fragment.
        else {
            // Send result to your TargetFragment.
            // See (Your) TargetFragment.onActivityResult()
            getTargetFragment().onActivityResult(getTargetRequestCode(), resultCode, data);
        }
    }

    private void buttonNoClick() {
        int resultCode = Activity.RESULT_CANCELED;
        Intent data  = null;

         // Open this DialogFragment from an Activity.
        if(this.listener != null)  {
            this.listener.onYesNoResultDialog(resultCode, data);
        }
        // Open this DialogFragment from another Fragment.
        else {
            // Send result to your TargetFragment.
            // See (Your) TargetFragment.onActivityResult()
            getTargetFragment().onActivityResult(getTargetRequestCode(), resultCode, data);
        }
    }

}
MainActivity.java
package org.o7planning.dialogfragmentexample;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.DialogFragment;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;

import android.app.Activity;
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
        implements YesNoDialogFragment.YesNoDialogFragmentListener {

    private Button buttonShow;
    private TextView textView;

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

        this.buttonShow = (Button) this.findViewById(R.id.button_show);
        this.textView = (TextView) this.findViewById(R.id.textView);

        this.buttonShow.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                buttonShowClicked();
            }
        });
    }

    // User click on "Show Dialog" button.
    private void buttonShowClicked()  {
        this.textView.setText("---");

        // Create YesNoDialogFragment
        DialogFragment dialogFragment = new YesNoDialogFragment();

        // Arguments:
        Bundle args = new Bundle();
        args.putString(YesNoDialogFragment.ARG_TITLE, "Confirmation");
        args.putString(YesNoDialogFragment.ARG_MESSAGE, "Do you like this example?");
        dialogFragment.setArguments(args);

        FragmentManager fragmentManager = this.getSupportFragmentManager();

        // Show:
        dialogFragment.show(fragmentManager, "Dialog");
    }

    @Override
    public void onAttachFragment(Fragment fragment) {
        if (fragment instanceof YesNoDialogFragment) {
            YesNoDialogFragment yesNoDialogFragment = (YesNoDialogFragment) fragment;
            yesNoDialogFragment.setOnYesNoDialogFragmentListener(this);
        }
    }

    // Implement method of YesNoDialogFragment.YesNoDialogFragmentListener
    @Override
    public void onYesNoResultDialog(int resultCode, @Nullable Intent data) {
        if(resultCode == Activity.RESULT_OK) {
            String value1 = data.getStringExtra("key1"); // ...
            this.textView.setText("You select YES");
        } else if(resultCode == Activity.RESULT_CANCELED) {
            this.textView.setText("You select NO");
        } else {
            this.textView.setText("You don't select");
        }
    }

}
Below is the code to create and display YesNoDialogFragment from another Fragment.
ExampleFragment.java
package org.o7planning.dialogfragmentexample;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

import androidx.annotation.Nullable;
import androidx.fragment.app.DialogFragment;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

public class ExampleFragment extends Fragment {

    private static final int REQUEST_CODE_YESNO_DIALOG_FRAGMENT = 1000;
    
    public ExampleFragment() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_example, container, false);
    }

    // Call this method to show YesNoDialogFragment
    private void showYesNoDialogFragment() {
        // Create YesNoDialogFragment
        DialogFragment dialogFragment = new YesNoDialogFragment();

        // Arguments:
        Bundle args = new Bundle();
        args.putString(YesNoDialogFragment.ARG_TITLE, "Confirmation");
        args.putString(YesNoDialogFragment.ARG_MESSAGE, "Do you like this example?");
        dialogFragment.setArguments(args);

        // YesNoDialogFragment will return results for targetFragment.
        // So, Need to Override onActivityResult() method, to get results.
        Fragment targetFragment = this;

        // IMPORTANT!!
        dialogFragment.setTargetFragment(targetFragment, REQUEST_CODE_YESNO_DIALOG_FRAGMENT);

        FragmentManager fragmentManager = this.getFragmentManager();
        // Show:
        dialogFragment.show(fragmentManager, "Dialog");
    }

    // Results are returned by YesNoDialogFragment.
    @Override
    public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if(requestCode == REQUEST_CODE_YESNO_DIALOG_FRAGMENT) {
            if(resultCode == Activity.RESULT_OK) {
                Toast.makeText(this.getContext(), "You select YES", Toast.LENGTH_LONG).show();
            } else if(resultCode == Activity.RESULT_CANCELED) {
                Toast.makeText(this.getContext(), "You select NO", Toast.LENGTH_LONG).show();
            }
        }
    }
}

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