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androidlistviewandroid-studioandroid-listfragment

ListFragment in Android Studio


I was going through tutorials online trying to understand how a ListFragment works and how do we use it.

The tutorials were a bit vague and I could not understand how it works exactly nor was I able to implement a ListFragment on Android Studio.

Could someone please provide details on how a ListFragment works and how do I implement it on Android Studio.

Also, how do I define a ListView inside a fragment without using ListFragment?


Solution

  • Regarding the last question:

    Also, how do I define a ListView inside a fragment without using ListFragment?

    I have code that might help.

    Here is the MainActivity.java, which includes a Fragment:

        public class MainActivity extends ActionBarActivity {
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            if (savedInstanceState == null) {
                getSupportFragmentManager().beginTransaction()
                        .add(R.id.container, new MusicFragment())
                        .commit();
            }
        }
    
    
        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.menu_main, menu);
            return true;
        }
    
        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            // Handle action bar item clicks here. The action bar will
            // automatically handle clicks on the Home/Up button, so long
            // as you specify a parent activity in AndroidManifest.xml.
            int id = item.getItemId();
    
            //noinspection SimplifiableIfStatement
            if (id == R.id.action_settings) {
                Intent i = new Intent(this, SettingsActivity.class);
                startActivity(i);
                return true;
            }
    
            return super.onOptionsItemSelected(item);
        }
    
        /**
         * A placeholder fragment containing a simple view.
         */
        public static class MusicFragment extends Fragment {
    
            ListView list;
            String[] text = { "House of Whispers","Hot Lunch", "Number of the Beast", "Killers"};
            Integer[] imageId = { R.drawable.hotlunch1, R.drawable.hotlunch2,
                    R.drawable.ironmaiden1, R.drawable.ironmaiden2 };
    
            public MusicFragment() {
            }
    
            @Override
            public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                     Bundle savedInstanceState) {
                View rootView = inflater.inflate(R.layout.fragment_main, container, false);
    
                list = (ListView) rootView.findViewById(R.id.ListView);
                CustomAdapter adapter = new CustomAdapter(getActivity() , text, imageId );
                list.setAdapter(adapter);
    
                Log.d("CustomAdapter", "MusicFragment onCreateView successful");
    
                return rootView;
            }
    
            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
    
    
            }
    
        }
    }
    

    fragment_main.xml:

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
        android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:paddingTop="@dimen/activity_vertical_margin"
        android:paddingBottom="@dimen/activity_vertical_margin"
        tools:context=".MainActivity$PlaceholderFragment">
    
        <ListView
            android:id="@+id/ListView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" >
        </ListView>
    
    </RelativeLayout>
    

    Edit: As requested, here is the CustomAdapter:

    public class CustomAdapter extends ArrayAdapter<String> {
        private final Activity _context;
        private final String[] _text;
        private final Integer[] _imageId;
    
        public CustomAdapter(Activity context, String[] text, Integer[] imageId) {
            super(context, R.layout.list_item, text);
            this._context = context;
            this._text = text;
            this._imageId = imageId;
        }
    
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
    
            LayoutInflater inflater = _context.getLayoutInflater();
            View rowView = inflater.inflate(R.layout.list_item, null, true);
            TextView txtTitle = (TextView) rowView.findViewById(R.id.text);
            ImageView imageView = (ImageView) rowView.findViewById(R.id.icon);
            txtTitle.setText(_text[position]);
            imageView.setImageResource(_imageId[position]);
    
            return rowView;
        }
    
    }