Java tutorial
/* * Copyright 2014 istvank.eu * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package eu.istvank.apps.lenslog.fragments; import android.app.Activity; import android.content.SharedPreferences; import android.content.res.Configuration; import android.os.Bundle; import android.preference.PreferenceManager; import android.support.v4.app.Fragment; import android.support.v4.widget.DrawerLayout; import android.support.v7.app.ActionBar; import android.support.v7.app.ActionBarActivity; import android.support.v7.app.ActionBarDrawerToggle; 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 eu.istvank.apps.lenslog.R; import eu.istvank.apps.lenslog.activities.MainActivity; /** * 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 { /** * A pointer to the current callbacks instance (the Activity). */ private NavigationDrawerCallbacks mCallbacks; private DrawerLayout mDrawerLayout; private ListView mDrawerListView; private View mFragmentContainerView; private int mCurrentSelectedPosition = 0; public static final int SECTION_CALENDAR = 0; public static final int SECTION_LENSES = 1; public NavigationDrawerFragment() { } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setRetainInstance(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>(getActivity().getBaseContext(), //getActionBar().getThemedContext(), android.R.layout.simple_list_item_activated_1, android.R.id.text1, new String[] { getString(R.string.title_section_calendar), getString(R.string.title_section_lenses) })); 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(Activity host, int fragmentId, DrawerLayout drawerLayout) { mFragmentContainerView = host.findViewById(fragmentId); mDrawerLayout = drawerLayout; } 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."); } } /** * Set the callback to null so we don't accidentally leak the Activity instance. */ @Override public void onDetach() { super.onDetach(); mCallbacks = null; } @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); // do not show Settings item if showing Settings fragment Fragment frgSettings = getFragmentManager().findFragmentByTag(MainActivity.FRAGMENT_SETTINGS); if (frgSettings != null && frgSettings.isVisible()) { menu.removeItem(R.id.action_settings); } showGlobalContextActionBar(); } super.onCreateOptionsMenu(menu, inflater); } @Override public boolean onOptionsItemSelected(MenuItem item) { if (item.getItemId() == R.id.action_settings) { Toast.makeText(getActivity(), "Example action.", Toast.LENGTH_SHORT).show(); 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); } }