ActionBarWithDrawerLayout.java

/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * 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 com.example.android.supportv7.app;

import com.example.android.supportv7.R;
import com.example.android.supportv7.Shakespeare;

import android.content.res.Configuration;
import android.os.Bundle;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class ActionBarWithDrawerLayout extends AppCompatActivity {
    private DrawerLayout mDrawerLayout;
    private ListView mDrawer;
    private TextView mContent;

    private ActionBarHelper mActionBar;

    private ActionBarDrawerToggle mDrawerToggle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.action_bar_drawer_layout);
        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawer = (ListView) findViewById(R.id.start_drawer);
        mContent = (TextView) findViewById(R.id.content_text);

        mDrawerLayout.setDrawerListener(new DemoDrawerListener());

        // The drawer title must be set in order to announce state changes when
        // accessibility is turned on. This is typically a simple description,
        // e.g. "Navigation".
        mDrawerLayout.setDrawerTitle(GravityCompat.START, getString(R.string.drawer_title));

        mDrawer.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,
                Shakespeare.TITLES));
        mDrawer.setOnItemClickListener(new DrawerItemClickListener());

        mActionBar = createActionBarHelper();
        mActionBar.init();

        // ActionBarDrawerToggle provides convenient helpers for tying together the
        // prescribed interactions between a top-level sliding drawer and the action bar.
        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
                R.string.drawer_open, R.string.drawer_close);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);

        // Sync the toggle state after onRestoreInstanceState has occurred.
        mDrawerToggle.syncState();
    }

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

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

    /**
     * This list item click listener implements very simple view switching by changing
     * the primary content text. The drawer is closed when a selection is made.
     */
    private class DrawerItemClickListener implements ListView.OnItemClickListener {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            mContent.setText(Shakespeare.DIALOGUE[position]);
            mActionBar.setTitle(Shakespeare.TITLES[position]);
            mDrawerLayout.closeDrawer(mDrawer);
        }
    }

    /**
     * A drawer listener can be used to respond to drawer events such as becoming
     * fully opened or closed. You should always prefer to perform expensive operations
     * such as drastic relayout when no animation is currently in progress, either before
     * or after the drawer animates.
     *
     * When using ActionBarDrawerToggle, all DrawerLayout listener methods should be forwarded
     * if the ActionBarDrawerToggle is not used as the DrawerLayout listener directly.
     */
    private class DemoDrawerListener implements DrawerLayout.DrawerListener {
        @Override
        public void onDrawerOpened(View drawerView) {
            mDrawerToggle.onDrawerOpened(drawerView);
            mActionBar.onDrawerOpened();
        }

        @Override
        public void onDrawerClosed(View drawerView) {
            mDrawerToggle.onDrawerClosed(drawerView);
            mActionBar.onDrawerClosed();
        }

        @Override
        public void onDrawerSlide(View drawerView, float slideOffset) {
            mDrawerToggle.onDrawerSlide(drawerView, slideOffset);
        }

        @Override
        public void onDrawerStateChanged(int newState) {
            mDrawerToggle.onDrawerStateChanged(newState);
        }
    }

    /**
     * Create a compatible helper that will manipulate the action bar if available.
     */
    private ActionBarHelper createActionBarHelper() {
        return new ActionBarHelper();
    }

    /**
     * Action bar helper for use on ICS and newer devices.
     */
    private class ActionBarHelper {
        private final ActionBar mActionBar;
        private CharSequence mDrawerTitle;
        private CharSequence mTitle;

        ActionBarHelper() {
            mActionBar = getSupportActionBar();
        }

        public void init() {
            mActionBar.setDisplayHomeAsUpEnabled(true);
            mActionBar.setDisplayShowHomeEnabled(false);
            mTitle = mDrawerTitle = getTitle();
        }

        /**
         * When the drawer is closed we restore the action bar state reflecting
         * the specific contents in view.
         */
        public void onDrawerClosed() {
            mActionBar.setTitle(mTitle);
        }

        /**
         * When the drawer is open we set the action bar to a generic title.
         * The action bar should only contain data relevant at the top level of
         * the nav hierarchy represented by the drawer, as the rest of your content
         * will be dimmed down and non-interactive.
         */
        public void onDrawerOpened() {
            mActionBar.setTitle(mDrawerTitle);
        }

        public void setTitle(CharSequence title) {
            mTitle = title;
        }
    }
}