content: package me.drakeet.androidviewhoverdemo;
  
  import android.content.Intent;
  import android.net.Uri;
  import android.support.v4.widget.SwipeRefreshLayout;
  import android.support.v7.app.ActionBarActivity;
  import android.app.Activity;
  import android.support.v7.app.ActionBar;
  import android.support.v4.app.Fragment;
  import android.support.v4.app.ActionBarDrawerToggle;
  import android.support.v4.view.GravityCompat;
  import android.support.v4.widget.DrawerLayout;
  import android.content.SharedPreferences;
  import android.content.res.Configuration;
  import android.os.Bundle;
  import android.preference.PreferenceManager;
  import android.view.LayoutInflater;
  import android.view.Menu;
  import android.view.MenuInflater;
  import android.view.MenuItem;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.AdapterView;
  import android.widget.ArrayAdapter;
  import android.widget.ListView;
  import android.widget.Toast;
  
  import butterknife.InjectView;
  
  /**
   * Fragment used for managing interactions for and presentation of a navigation drawer.
   * See the <a href="https://developer.android.com/design/patterns/navigation-drawer.html#Interaction">
   * design guidelines</a> for a complete explanation of the behaviors implemented here.
   */
  public class NavigationDrawerFragment extends Fragment {
  
      /**
       * Remember the position of the selected item.
       */
      private static final String STATE_SELECTED_POSITION = "selected_navigation_drawer_position";
  
      /**
       * Per the design guidelines, you should show the drawer on launch until the user manually
       * expands it. This shared preference tracks this.
       */
      private static final String PREF_USER_LEARNED_DRAWER = "navigation_drawer_learned";
  
      /**
       * A pointer to the current callbacks instance (the Activity).
       */
      private NavigationDrawerCallbacks mCallbacks;
  
      /**
       * Helper component that ties the action bar to the navigation drawer.
       */
      private ActionBarDrawerToggle mDrawerToggle;
  
      private DrawerLayout mDrawerLayout;
      private ListView mDrawerListView;
      private View mFragmentContainerView;
  
      private int mCurrentSelectedPosition = 0;
      private boolean mFromSavedInstanceState;
      private boolean mUserLearnedDrawer;
  
      public NavigationDrawerFragment() {
      }
  
      @Override
      public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
  
          // Read in the flag indicating whether or not the user has demonstrated awareness of the
          // drawer. See PREF_USER_LEARNED_DRAWER for details.
          SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(getActivity());
          mUserLearnedDrawer = sp.getBoolean(PREF_USER_LEARNED_DRAWER, false);
  
          if (savedInstanceState != null) {
              mCurrentSelectedPosition = savedInstanceState.getInt(STATE_SELECTED_POSITION);
              mFromSavedInstanceState = true;
          }
  
          // Select either the default item (0) or the last selected item.
          selectItem(mCurrentSelectedPosition);
      }
  
      @Override
      public void onActivityCreated(Bundle savedInstanceState) {
          super.onActivityCreated(savedInstanceState);
          // Indicate that this fragment would like to influence the set of actions in the action bar.
          setHasOptionsMenu(true);
      }
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
          mDrawerListView = (ListView) inflater.inflate(
                  R.layout.fragment_navigation_drawer, container, false
          );
          mDrawerListView.setOnItemClickListener(
                  new AdapterView.OnItemClickListener() {
                      @Override
                      public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                          selectItem(position);
                      }
                  }
          );
          mDrawerListView.setAdapter(
                  new ArrayAdapter<String>(
                          getActionBar().getThemedContext(), android.R.layout.simple_list_item_1, android.R.id.text1, new String[] {getString(R.string.title_section1), getString(R.string.title_section2), getString(R.string.title_section3),}
                  )
          );
          mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
          return mDrawerListView;
      }
  
      public boolean isDrawerOpen() {
          return mDrawerLayout != null && mDrawerLayout.isDrawerOpen(mFragmentContainerView);
      }
  
      /**
       * Users of this fragment must call this method to set up the navigation drawer interactions.
       *
       * @param fragmentId   The android:id of this fragment in its activity's layout.
       * @param drawerLayout The DrawerLayout containing this fragment's UI.
       */
      public void setUp(int fragmentId, DrawerLayout drawerLayout) {
          mFragmentContainerView = getActivity().findViewById(fragmentId);
          mDrawerLayout = drawerLayout;
  
          // set a custom shadow that overlays the main content when the drawer opens
          mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
          // set up the drawer's list view with items and click listener
  
          ActionBar actionBar = getActionBar();
          actionBar.setDisplayHomeAsUpEnabled(true);
          actionBar.setHomeButtonEnabled(true);
  
          // ActionBarDrawerToggle ties together the the proper interactions
          // between the navigation drawer and the action bar app icon.
          mDrawerToggle = new ActionBarDrawerToggle(
                  getActivity(),                    /* host Activity */
                  mDrawerLayout,                    /* DrawerLayout object */
                  R.drawable.ic_drawer,             /* nav drawer image to replace 'Up' caret */
                  R.string.navigation_drawer_open,  /* "open drawer" description for accessibility */
                  R.string.navigation_drawer_close  /* "close drawer" description for accessibility */
          ) {
              @Override
              public void onDrawerClosed(View drawerView) {
                  super.onDrawerClosed(drawerView);
                  if (!isAdded()) {
                      return;
                  }
  
                  getActivity().supportInvalidateOptionsMenu(); // calls onPrepareOptionsMenu()
              }
  
              @Override
              public void onDrawerOpened(View drawerView) {
                  super.onDrawerOpened(drawerView);
                  if (!isAdded()) {
                      return;
                  }
  
                  if (!mUserLearnedDrawer) {
                      // The user manually opened the drawer; store this flag to prevent auto-showing
                      // the navigation drawer automatically in the future.
                      mUserLearnedDrawer = true;
                      SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(getActivity());
                      sp.edit().putBoolean(PREF_USER_LEARNED_DRAWER, true).apply();
                  }
  
                  getActivity().supportInvalidateOptionsMenu(); // calls onPrepareOptionsMenu()
              }
          };
  
          // If the user hasn't 'learned' about the drawer, open it to introduce them to the drawer,
          // per the navigation drawer design guidelines.
          if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
              mDrawerLayout.openDrawer(mFragmentContainerView);
          }
  
          // Defer code dependent on restoration of previous instance state.
          mDrawerLayout.post(
                  new Runnable() {
                      @Override
                      public void run() {
                          mDrawerToggle.syncState();
                      }
                  }
          );
  
          mDrawerLayout.setDrawerListener(mDrawerToggle);
      }
  
      private void selectItem(int position) {
          mCurrentSelectedPosition = position;
          if (mDrawerListView != null) {
              mDrawerListView.setItemChecked(position, true);
          }
          if (mDrawerLayout != null) {
              mDrawerLayout.closeDrawer(mFragmentContainerView);
          }
          if (mCallbacks != null) {
              mCallbacks.onNavigationDrawerItemSelected(position);
          }
      }
  
      @Override
      public void onAttach(Activity activity) {
          super.onAttach(activity);
          try {
              mCallbacks = (NavigationDrawerCallbacks) activity;
          } catch (ClassCastException e) {
              throw new ClassCastException("Activity must implement NavigationDrawerCallbacks.");
          }
      }
  
      @Override
      public void onDetach() {
          super.onDetach();
          mCallbacks = null;
      }
  
      @Override
      public void onSaveInstanceState(Bundle outState) {
          super.onSaveInstanceState(outState);
          outState.putInt(STATE_SELECTED_POSITION, mCurrentSelectedPosition);
      }
  
      @Override
      public void onConfigurationChanged(Configuration newConfig) {
          super.onConfigurationChanged(newConfig);
          // Forward the new configuration the drawer toggle component.
          mDrawerToggle.onConfigurationChanged(newConfig);
      }
  
      @Override
      public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
          // If the drawer is open, show the global app actions in the action bar. See also
          // showGlobalContextActionBar, which controls the top-left area of the action bar.
          if (mDrawerLayout != null && isDrawerOpen()) {
              inflater.inflate(R.menu.global, menu);
              showGlobalContextActionBar();
          }
          super.onCreateOptionsMenu(menu, inflater);
      }
  
      @Override
      public boolean onOptionsItemSelected(MenuItem item) {
          if (mDrawerToggle.onOptionsItemSelected(item)) {
              return true;
          }
  
          if (item.getItemId() == R.id.action_about) {
              Intent it = new Intent(Intent.ACTION_VIEW);
              it.setData(Uri.parse(getString(R.string.about_developer)));
              it = Intent.createChooser(it, null);
              startActivity(it);
              return true;
          }
  
          return super.onOptionsItemSelected(item);
      }
  
      /**
       * Per the navigation drawer design guidelines, updates the action bar to show the global app
       * 'context', rather than just what's in the current screen.
       */
      private void showGlobalContextActionBar() {
          ActionBar actionBar = getActionBar();
          actionBar.setDisplayShowTitleEnabled(true);
          actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
          actionBar.setTitle(R.string.app_name);
      }
  
      private ActionBar getActionBar() {
          return ((ActionBarActivity) getActivity()).getSupportActionBar();
      }
  
      /**
       * Callbacks interface that all activities using this fragment must implement.
       */
      public static interface NavigationDrawerCallbacks {
          /**
           * Called when an item in the navigation drawer is selected.
           */
          void onNavigationDrawerItemSelected(int position);
      }
  }
  