de.zell.android.util.activities.MainNavigationActivity.java Source code

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Here is the source code for de.zell.android.util.activities.MainNavigationActivity.java

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/*
 * Copyright (C) 2015 Christopher Zell <zelldon91@googlemail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package de.zell.android.util.activities;

import android.app.ActionBar;
import android.content.IntentFilter;
import android.content.res.Configuration;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.view.MenuItem;
import android.view.View;
import android.widget.*;
import de.zell.android.util.R;
import de.zell.android.util.fragments.ActionBarTitleManager;
import de.zell.android.util.fragments.FragmentReplacer;

/**
 * Represents the main navigation activity with a navigation drawer. On the left
 * side of the drawer displays the navigation to other existing views. If some
 * of them are selected the current fragment are replaced with the selected view
 * (respectively fragment). That means it exists only one main fragment in the
 * center which will be replaced every time.
 *
 * Influenced by the Android Navigation Drawer Tutorial:
 * https://developer.android.com/training/implementing-navigation/nav-drawer.html
 *
 * @author Christopher Zell <zelldon91@googlemail.com>
 */
public abstract class MainNavigationActivity extends FragmentActivity {

    /**
     * Drawer which will be used to draw the navigation on the left side.
     */
    private DrawerLayout mDrawerLayout;

    /**
     * The ListView which shows the fragments for the navigation.
     */
    private ListView mDrawerList;

    /**
     * The ActionBar toggle which enables to toggle the navigation bar.
     */
    private ActionBarDrawerToggle mDrawerToggle;

    /**
     * The title of the action bar.
     */
    private CharSequence mDrawerTitle;

    /**
     * The title of the current view.
     */
    private CharSequence mTitle;

    /**
     * The name of the applications.
     */
    private String[] applications;

    /**
     * Returns the navigation fragment array.
     * This array contains the fragments which correspond to the given fragment
     * names. If a specific name is selected in the navigation drawer the 
     * corresponding fragment is showed in the center of the application. 
     * 
     * @return the navigation fragments
     */
    protected abstract Fragment[] getNavigationFragments();

    /**
     * Returns the list adapter for the navigation list.
     * 
     * @return the list adapter
     */
    protected ListAdapter getNavigationListAdapter() {
        return new ArrayAdapter<String>(this, R.layout.drawer_list_item, applications);
    }

    /**
     * Returns the navigations fragment names which will be shown by
     * the navigation drawer.
     * 
     * @return the names of the fragments
     */
    protected abstract String[] getNavigationFragmentNames();

    private ViewFragmentBroadcastReciever reciever;

    protected ViewFragmentBroadcastReciever getBroadcastReciever() {
        return new ViewFragmentBroadcastReciever();
    }

    protected IntentFilter getIntentFilter() {
        IntentFilter filter = new IntentFilter();
        filter.addAction(IntentKeys.BROADCAST_VIEW_FRAGMENT);
        filter.addAction(IntentKeys.BROADCAST_HIDE_FRAGMENT);
        return filter;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_nav_drawer);

        mTitle = mDrawerTitle = getTitle();
        applications = getNavigationFragmentNames();
        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerList = (ListView) findViewById(R.id.left_drawer);

        // set a custom shadow that overlays the main content when the drawer opens
        mDrawerLayout.setDrawerShadow(R.drawable.ic_drawer_shadow, GravityCompat.START);
        // set up the drawer's list view with items and click listener
        mDrawerList.setAdapter(getNavigationListAdapter());

        mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
        initActionBar();

        // ActionBarDrawerToggle ties together the the proper interactions
        // between the sliding drawer and the action bar app icon
        mDrawerToggle = createActionBarDrawerToggle();
        mDrawerLayout.setDrawerListener(mDrawerToggle);
        ((DrawerItemClickListener) mDrawerList.getOnItemClickListener()).selectItem(0);
    }

    private void initActionBar() {
        ActionBar bar = getActionBar();
        // enable ActionBar app icon to behave as action to toggle nav drawer
        bar.setIcon(getActionBarIcon());
        bar.setDisplayHomeAsUpEnabled(true);
        bar.setHomeButtonEnabled(true);
    }

    protected int getActionBarIcon() {
        return R.drawable.ic_launcher;
    }

    /**
     * Returns the progress bar which could be used to show 
     * a progress of an async task or other task.
     * 
     * @return the main progress bar
     */
    public ProgressBar getProgressBar() {
        return (ProgressBar) this.findViewById(R.id.main_progress_bar);
    }

    /**
     * Creates a action bar drawer toggle object, which will be used
     * for the toggling of the drawer.
     * 
     * @return the drawer toggle object
     */
    private ActionBarDrawerToggle createActionBarDrawerToggle() {
        return new ActionBarDrawerToggle(this, /* host Activity */
                mDrawerLayout, /* DrawerLayout object */
                R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */
                R.string.drawer_open, /* "open drawer" description for accessibility */
                R.string.drawer_close /* "close drawer" description for accessibility */) {
            @Override
            public void onDrawerClosed(View view) {
                onDrawerChanged(mTitle);
            }

            @Override
            public void onDrawerOpened(View drawerView) {
                onDrawerChanged(mDrawerTitle);
            }

            /**
             * Will be called if the drawer was changed.
             * Sets the given title as ActionBar title and calls
             * the invalidateOptionsMenu to prepare the menu.
             */
            private void onDrawerChanged(CharSequence title) {
                getActionBar().setTitle(title);
                invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
            }
        };
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // The action bar home/up action should open or close the drawer.
        // ActionBarDrawerToggle will take care of this.
        return mDrawerToggle.onOptionsItemSelected(item);
    }

    /**
     * Starts the searching with the tipped query. The query is tipped in on the
     * navigation bar (left).
     *
     * @param query the value which is searched for
     */
    protected abstract void startSearch(String query);

    /**
     * The click listener for the ListView in the navigation drawer.
     */
    private class DrawerItemClickListener implements ListView.OnItemClickListener {

        /**
         * Contains all existing main fragments.
         */
        private final Fragment fragments[];

        public DrawerItemClickListener() {
            fragments = getNavigationFragments();
            for (int i = 0; i < fragments.length; i++) {
                Fragment frg = fragments[i];
                Bundle title = frg.getArguments();
                if (title == null)
                    title = new Bundle();
                title.putString(ActionBarTitleManager.ARG_ACTION_BAR_TITLE, applications[i % applications.length]);
                frg.setArguments(title);
            }
        }

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            selectItem(position);
        }

        /**
         * Selects the item which the user has clicked and starts the clicked
         * fragment (application).
         *
         * @param position the position in the list
         */
        public void selectItem(int position) {
            // update the main content by replacing fragments
            FragmentReplacer.replace(getSupportFragmentManager(), getFragmentForChoice(position),
                    FragmentReplacer.MAIN_CONTENT);
            // update selected item and title, then close the drawer
            mDrawerList.setItemChecked(position, true);
            setTitle(applications[position % applications.length]);
            mDrawerLayout.closeDrawer(mDrawerList);
        }

        /**
         * Returns for the given choice the corresponding fragment.
         * 
         * @param choice        the choice
         * @return              the corresponding fragment
         */
        private Fragment getFragmentForChoice(int choice) {
            return fragments[choice % fragments.length];
        }
    }

    @Override
    public void setTitle(CharSequence title) {
        mTitle = title;
        getActionBar().setTitle(mTitle);
    }

    /*
     * When using the ActionBarDrawerToggle, you must call it during
     * onPostCreate() and onConfigurationChanged()...
     */
    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        // Sync the toggle state after onRestoreInstanceState has occurred.
        mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        // Pass any configuration change to the drawer toggls
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

    @Override
    protected void onStart() {
        super.onStart();
        reciever = getBroadcastReciever();
        registerReceiver(reciever, getIntentFilter());
    }

    @Override
    protected void onStop() {
        super.onStop();
        unregisterReceiver(reciever);
    }
}