Tukukkk

I just got an idea to implement a BottomNavigationView to my app.

But the problem is that how/where do i start converting my existing activities, class and adapter to be fragments?

Here is a picture demonstrating what i have now

I have 3 properties in my BottomNavigationView: Main (list of songs), Radio (empty - not begun on yet) and Collections (my playlist is gonna appear here)

These are my java classes i want to convert to a fragment

These are my layout(XML) files

Any help is appreciated as im really confused on how to accomplish this with my current setup.

This is my CustomAdapter class:

public class ListViewAdapter extends BaseAdapter {



//Create variables

MediaPlayer mediaPlayer;

int layout;

Song currentSong;

ArrayList<Song> arrayList;

Context context;



public ListViewAdapter(int layout, ArrayList<Song> arrayList, Context 

context) {

    this.layout = layout;

    this.arrayList = arrayList;

    this.context = context;

}



private class Viewholder {

    TextView artistTxt, songNameTxt;

    ImageView playB, stopB;

}



@Override

public int getCount() {

    return arrayList.size();

}



@Override

public Object getItem(int position) {

    return null;

}



@Override

public long getItemId(int position) {

    return 0;

}



@Override

public View getView(int position, View view, ViewGroup parent) {



    final Viewholder viewholder;



    if (view == null) {

        viewholder = new Viewholder();



        LayoutInflater layoutInflater = (LayoutInflater) 

context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        view = layoutInflater.inflate(layout, null);



        viewholder.artistTxt = (TextView) 

view.findViewById(R.id.artistTxt);

        viewholder.songNameTxt = (TextView) 

view.findViewById(R.id.songNameTxt);

        viewholder.playB = (ImageView) view.findViewById(R.id.playB);

        viewholder.stopB = (ImageView) view.findViewById(R.id.stopB);

        view.setTag(viewholder);

    } else {

        viewholder = (Viewholder) view.getTag();

    }



    final Song song = arrayList.get(position);



    viewholder.artistTxt.setText(song.getArtist());

    viewholder.songNameTxt.setText(song.getSongName());



    //get all songs

    mediaPlayer = MediaPlayer.create(context, song.getSong());



    viewholder.playB.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View v) {



            if (currentSong == null) {

                mediaPlayer = MediaPlayer.create(context, song.getSong());

            }



            //if mediaplayer is not null and my current song is not equal 

to the new song i clicked on

            if (mediaPlayer != null && currentSong != song) {



                //resets the mediaplayer and creates a new song from the 

position in the list

                mediaPlayer.reset();



                mediaPlayer = MediaPlayer.create(context, song.getSong());

                viewholder.playB.setImageResource(R.drawable.play_black);



                mediaPlayer.start();

                viewholder.playB.setImageResource(R.drawable.pause_black);

            } else {

                mediaPlayer.pause();

                viewholder.playB.setImageResource(R.drawable.play_black);

            }



            //check if current song is null or the newly clicked song is 

equal to my current song

            //if true then assign the newly clicked song as my CURRENT one

            //--so it doesnt play the same song for every single one

            if (currentSong == null || song != currentSong) {

                currentSong = song;

            }

        }

    });



    //stop song

    viewholder.stopB.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View v) {

            //stops my current song and make it null

            if (currentSong != null) {

                mediaPlayer.stop();

                mediaPlayer.release();



                currentSong = null;

                viewholder.playB.setImageResource(R.drawable.play_black);

            }

        }

    });

    return view;

}

And this is my SongListActivity where i add my songs and set my adapter:

public class SongListActivity extends AppCompatActivity {



ArrayList<Song> arrayList;

ListView listView;

ListViewAdapter adapter;



@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_song_list);



    BottomNavigationView bottomNavigationView = (BottomNavigationView) findViewById(R.id.navigationBar);

    bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {

        @Override

        public boolean onNavigationItemSelected(@NonNull MenuItem menuItem) {

            switch (menuItem.getItemId()) {

                case R.id.action_main:

                    startActivity(new Intent(getApplicationContext(), SongListActivity.class));

                    break;



                case R.id.action_collection:

                    startActivity(new Intent(getApplicationContext(), CollectionActivity.class));

                    break;

            }



            return true;

        }

    });



    //Actionbar modified

    getSupportActionBar().setTitle("Song list");



    //Find my listview

    listView = (ListView) findViewById(R.id.listView);



    //create a new arraylist object

    arrayList = new ArrayList<>();



    //Add songs to my list

    arrayList.add(new Song("Beyonce", "-Formation", R.raw.beyonce_formation));

    arrayList.add(new Song("Chris Brown", "-Hope You Do", R.raw.chrisbrown_hopeyoudo));

    arrayList.add(new Song("Akon ft. Colby'O'Donis", "-Beautiful", R.raw.akon_beautiful_ft_colbyodonis_kardinaloffishall));

    arrayList.add(new Song("Akon", "-Beautiful", R.raw.akon_dontmatter));

    arrayList.add(new Song("Akon", "-Locked Up", R.raw.akon_lockedup_ft_stylesp));

    arrayList.add(new Song("Ava Max", "-Sweet but Psycho", R.raw.avamax_sweetbutpsycho));

    arrayList.add(new Song("Tupac and Biggie ft. Akon Remix", "-Ghetto", R.raw.tupacbiggieakon_ghetto));



    //Create a new adapter of my custom adapter and assign its values

    adapter = new ListViewAdapter(R.layout.listview_customlayout, arrayList, this);



    //Set my listview to my custom adapter

    listView.setAdapter(adapter);

}

}

My CustomListViewLayout is like this:

<?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:background="@color/white">



<ImageView

    android:id="@+id/musicLogo"

    android:layout_width="40sp"

    android:layout_height="40sp"

    android:src="@drawable/musiclogo" />



<TextView

    android:id="@+id/artistTxt"

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:layout_toRightOf="@id/musicLogo"

    android:text="Artist"

    android:textColor="@color/black"

    android:textSize="15sp" />



<TextView

    android:id="@+id/songNameTxt"

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:layout_below="@id/artistTxt"

    android:layout_toRightOf="@id/musicLogo"

    android:text="Song Name"

    android:textColor="#11ca6b" />



<ImageView

    android:id="@+id/playB"

    android:layout_width="30sp"

    android:layout_height="30sp"

    android:layout_marginTop="4sp"

    android:layout_toLeftOf="@id/stopB"

    android:src="@drawable/play_black" />



<ImageView

    android:id="@+id/stopB"

    android:layout_width="30sp"

    android:layout_height="30sp"

    android:layout_alignParentRight="true"

    android:layout_marginTop="4sp"

    android:src="@drawable/stop_black" />



 </RelativeLayout>

Thank you.

This is a question that can spawn diverse answers depending on how one looks at it, as in one wants to be pragmatic, or one wants to be architecturally good, etc.

I can suggest a quick (and easy) and not-so-quick (but fairly easy and good) way to tackle your problem.

1. 
   Quick and easy approach; make a new activity, say, called NavigationActivity. Among other things, this can be the activity that:
   
   
   
   
   • Will be your main launcher activity.
   
   
   • Will implement an UI with a bottom navigation bar and a container for
     child fragments. Now, the bottom navigation bar will be the
     BottomNavigationView and the container can be a ViewPager.
   
   
   
   

After that, convert your existing activities to fragments. It should be fairly straight forward.

And then the main trick is to use these converted fragments as the children of the NavigationActivity that you created above.

In summary, you convert your existing activities to fragments as it is. And then, create a new parent for them, where parent houses them and also provides navigation to them using a Bottom Navigation bar.

2. 
   Not-so-quick, but suggested approach; this will require you to invest more time into your project but will be beneficial in the long run. It involves investing into a good architecture for your app.

Firstly, if you have not yet, then invest time familiarising yourself with app architectures like MVP, MVVM and more and make a decision on using one for your app. If you do not want to read all, then see Android Arch Components.

I'm sure you will have the right way of transforming your fragments once you are done with the above. You can still refactor the app using approach (1), but you will be doing more. Depending upon how much business logic you have housed in the individual activities, it will make sense to keep the NavigationActivity very lean, and then create ViewModel (or Presenter or something similar) for each new functionality (perhaps for each new fragment).

In summary, essentially, this approach is all about taking a more mature engineering route.