OpeningHoursListFragment.java

package de.tum.in.tumcampusapp.fragments;

import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.view.View;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;

import de.tum.in.tumcampusapp.R;

/**
 * A list fragment representing a list of Items. This fragment also supports
 * tablet devices by allowing list items to be given an 'activated' state upon
 * selection. This helps indicate which item is currently being viewed in a
 * {@link OpeningHoursDetailFragment}.
 * <p/>
 * Activities containing this fragment MUST implement the {@link Callbacks}
 * interface.
 */
public class OpeningHoursListFragment extends ListFragment {

    /**
     * The serialization (saved instance state) Bundle key representing the
     * activated item position. Only used on tablets.
     */
    private static final String STATE_ACTIVATED_POSITION = "activated_position";

    /**
     * The current activated item position. Only used on tablets.
     */
    private int mActivatedPosition = ListView.INVALID_POSITION;

    /**
     * The fragment's current callback object, which is notified of list item
     * clicks.
     */
    private Callbacks mCallbacks = S_DUMMY_CALLBACKS;

    /**
     * A callback interface that all activities containing this fragment must
     * implement. This mechanism allows activities to be notified of item
     * selections.
     */
    public interface Callbacks {
        /**
         * Callback for when an item has been selected.
         *
         * @param pos  Index of the item
         * @param name Name of the item
         */
        void onItemSelected(int pos, String name);
    }

    /**
     * A dummy implementation of the {@link Callbacks} interface that does
     * nothing. Used only when this fragment is not attached to an activity.
     */
    private static final Callbacks S_DUMMY_CALLBACKS = new Callbacks() {
        @Override
        public void onItemSelected(int id, String name) {
            // Dummy callback
        }
    };

    public OpeningHoursListFragment() {
        /*
         * Mandatory empty constructor for the fragment manager to instantiate the
         * fragment (e.g. upon screen orientation changes).
         */
    }

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

        // Activities containing this fragment must implement its callbacks.
        if (!(activity instanceof Callbacks)) {
            throw new IllegalStateException("Activity must implement fragment's callbacks.");
        }
        mCallbacks = (Callbacks) activity;
    }

    @SuppressLint("InlinedApi")
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        int layout = android.R.layout.simple_list_item_activated_1;

        String[] names = {getString(R.string.libraries),
                getString(R.string.information),
                getString(R.string.mensa_garching),
                getString(R.string.mensa_grosshadern),
                getString(R.string.mensa_city),
                getString(R.string.mensa_pasing),
                getString(R.string.mensa_weihenstephan)};

        setListAdapter(new ArrayAdapter<>(getActivity(), layout, android.R.id.text1, names));
    }

    @Override
    public void onDetach() {
        super.onDetach();

        // Reset the active callbacks interface to the dummy implementation.
        mCallbacks = S_DUMMY_CALLBACKS;
    }

    @Override
    public void onListItemClick(ListView listView, View view, int position, long id) {
        super.onListItemClick(listView, view, position, id);

        // Notify the active callbacks interface (the activity, if the
        // fragment is attached to one) that an item has been selected.
        final ListAdapter adapter = getListAdapter();
        mCallbacks.onItemSelected(position, adapter.getItem(position).toString());
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        if (mActivatedPosition != AdapterView.INVALID_POSITION) {
            // Serialize and persist the activated item position.
            outState.putInt(STATE_ACTIVATED_POSITION, mActivatedPosition);
        }
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        // Restore the previously serialized activated item position.
        if (savedInstanceState != null && savedInstanceState.containsKey(STATE_ACTIVATED_POSITION)) {
            setActivatedPosition(savedInstanceState.getInt(STATE_ACTIVATED_POSITION));
        }
    }

    private void setActivatedPosition(int position) {
        if (position == AdapterView.INVALID_POSITION) {
            getListView().setItemChecked(mActivatedPosition, false);
        } else {
            getListView().setItemChecked(position, true);
        }

        mActivatedPosition = position;
    }

    /**
     * Turns on activate-on-click mode. When this mode is on, list items will be
     * given the 'activated' state when touched.
     */
    public void setActivateOnItemClick(boolean activateOnItemClick) {
        // When setting CHOICE_MODE_SINGLE, ListView will automatically
        // give items the 'activated' state when touched.
        getListView().setChoiceMode(
                activateOnItemClick ? AbsListView.CHOICE_MODE_SINGLE
                        : AbsListView.CHOICE_MODE_NONE);
    }
}