title: Android - Back Button Navigation in Fragment
body: <p>Hello all I have created a simple app for learning purposes. I have placed a button in Fragment 1 of the app, once the button is triggered, it navigates to Fragment 2. I want to be able to go back to Fragment 1 using an actionbar back button as shown in the second picture. I have tried different ways to solve it and I just cant seem to get it right. </p>
  
  <p>So if someone could show me how to return from Fragment 2 to Fragment 1 that would be amazing. Thanks in advance. </p>
  
  <p>Here is the code i have right now. </p>
  
  <p>Picture 1
  <img src="https://i.stack.imgur.com/jpJzx.png" alt="enter image description here">Picture 2</p>
  
  <p><img src="https://i.stack.imgur.com/77TaM.png" alt="Such as the example below:"></p>
  
  <p>MainActivity:</p>
  
  <pre><code>package info.androidhive.slidingmenu;
  
  import info.androidhive.slidingmenu.adapter.NavDrawerListAdapter;
  import info.androidhive.slidingmenu.model.NavDrawerItem;
  
  import java.util.ArrayList;
  
  import android.annotation.SuppressLint;
  import android.app.Activity;
  import android.app.Fragment;
  import android.app.FragmentManager;
  import android.content.res.Configuration;
  import android.content.res.TypedArray;
  import android.os.Bundle;
  import android.support.v4.app.ActionBarDrawerToggle;
  import android.support.v4.widget.DrawerLayout;
  import android.util.Log;
  import android.view.Menu;
  import android.view.MenuItem;
  import android.view.View;
  import android.widget.AdapterView;
  import android.widget.ListView;
  
  public class MainActivity extends Activity {
      private DrawerLayout mDrawerLayout;
      private ListView mDrawerList;
      private ActionBarDrawerToggle mDrawerToggle;
  
      // nav drawer title
      private CharSequence mDrawerTitle;
  
      // used to store app title
      private CharSequence mTitle;
  
      // slide menu items
      private String[] navMenuTitles;
      private TypedArray navMenuIcons;
  
      private ArrayList&lt;NavDrawerItem&gt; navDrawerItems;
      private NavDrawerListAdapter adapter;
  
      @SuppressLint("NewApi")
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          mTitle = mDrawerTitle = getTitle();
  
          // load slide menu items
          navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
  
          // nav drawer icons from resources
          navMenuIcons = getResources()
                  .obtainTypedArray(R.array.nav_drawer_icons);
  
          mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
          mDrawerList = (ListView) findViewById(R.id.list_slidermenu);
  
          navDrawerItems = new ArrayList&lt;NavDrawerItem&gt;();
  
          // adding nav drawer items to array
          // Home
          navDrawerItems.add(new NavDrawerItem(navMenuTitles[0], navMenuIcons.getResourceId(0, -1)));
  
  
  
          // Recycle the typed array
          navMenuIcons.recycle();
  
          mDrawerList.setOnItemClickListener(new SlideMenuClickListener());
  
          // setting the nav drawer list adapter
          adapter = new NavDrawerListAdapter(getApplicationContext(),
                  navDrawerItems);
          mDrawerList.setAdapter(adapter);
  
          // enabling action bar app icon and behaving it as toggle button
          getActionBar().setDisplayHomeAsUpEnabled(true);
          getActionBar().setHomeButtonEnabled(true);
  
          mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
                  R.drawable.ic_drawer, //nav menu toggle icon
                  R.string.app_name, // nav drawer open - description for accessibility
                  R.string.app_name // nav drawer close - description for accessibility
          ) {
              public void onDrawerClosed(View view) {
                  getActionBar().setTitle(mTitle);
                  // calling onPrepareOptionsMenu() to show action bar icons
                  invalidateOptionsMenu();
              }
  
              public void onDrawerOpened(View drawerView) {
                  getActionBar().setTitle(mDrawerTitle);
                  // calling onPrepareOptionsMenu() to hide action bar icons
                  invalidateOptionsMenu();
              }
          };
          mDrawerLayout.setDrawerListener(mDrawerToggle);
  
          if (savedInstanceState == null) {
              // on first time display view for first nav item
              displayView(0);
          }
      }
  
      /**
       * Slide menu item click listener
       * */
      private class SlideMenuClickListener implements
              ListView.OnItemClickListener {
          @Override
          public void onItemClick(AdapterView&lt;?&gt; parent, View view, int position,
                  long id) {
              // display view for selected nav drawer item
              displayView(position);
          }
      }
  
      @Override
      public boolean onCreateOptionsMenu(Menu menu) {
          getMenuInflater().inflate(R.menu.main, menu);
          return true;
      }
  
      @Override
      public boolean onOptionsItemSelected(MenuItem item) {
          // toggle nav drawer on selecting action bar app icon/title
          if (mDrawerToggle.onOptionsItemSelected(item)) {
              return true;
          }
          // Handle action bar actions click
          switch (item.getItemId()) {
          case R.id.action_settings:
              return true;
          default:
              return super.onOptionsItemSelected(item);
          }
      }
  
      /* *
       * Called when invalidateOptionsMenu() is triggered
       */
      @Override
      public boolean onPrepareOptionsMenu(Menu menu) {
          // if nav drawer is opened, hide the action items
          boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
          menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
          return super.onPrepareOptionsMenu(menu);
      }
  
      /**
       * Diplaying fragment view for selected nav drawer list item
       * */
      private void displayView(int position) {
          // update the main content by replacing fragments
          Fragment fragment = null;
          switch (position) {
          case 0:
              fragment = new Fragment_1();
              break;
  
  
          default:
              break;
          }
  
          if (fragment != null) {
              FragmentManager fragmentManager = getFragmentManager();
              fragmentManager.beginTransaction()
                      .replace(R.id.frame_container, fragment).commit();
  
              // update selected item and title, then close the drawer
              mDrawerList.setItemChecked(position, true);
              mDrawerList.setSelection(position);
              setTitle(navMenuTitles[position]);
              mDrawerLayout.closeDrawer(mDrawerList);
          } else {
              // error in creating fragment
              Log.e("MainActivity", "Error in creating fragment");
          }
      }
  
      @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);
      }
  
  }
  </code></pre>
  
  <p>Fragment_1:</p>
  
  <pre><code>package info.androidhive.slidingmenu;
  
  import android.app.Fragment;
  import android.app.FragmentManager;
  import android.app.FragmentTransaction;
  import android.content.Intent;
  import android.os.Bundle;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.View.OnClickListener;
  import android.view.ViewGroup;
  import android.widget.Button;
  
  public class Fragment_1 extends Fragment implements OnClickListener{
      private Button button;
      public Fragment_1(){}
  
      @Override
  
      public View onCreateView(LayoutInflater inflater, ViewGroup container,
              Bundle savedInstanceState) {
  
          View rootView = inflater.inflate(R.layout.fragment_1, container, false);
  
          Button b = (Button) rootView.findViewById(R.id.button1);
          b.setOnClickListener(this);
  
          return rootView;
      }
  
      public void onClick(View v) {
  
          switch (v.getId()) {
          case R.id.button1:
  
              Fragment newFragment = new Fragment_2();
              FragmentTransaction transaction = getFragmentManager().beginTransaction();
  
              FragmentManager fragmentManager = getFragmentManager();
              fragmentManager.beginTransaction()
                      .replace(R.id.frame_container, newFragment).commit();
  
              break;
          }
      }
  
  
  }
  </code></pre>
  
  <p>Fragment_2:</p>
  
  <pre><code>package info.androidhive.slidingmenu;
  
  import android.app.Fragment;
  import android.os.Bundle;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.ViewGroup;
  
  public class Fragment_2 extends Fragment {
  
      public Fragment_2(){}
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container,
              Bundle savedInstanceState) {
  
          View rootView = inflater.inflate(R.layout.fragment_2, container, false);
  
          return rootView;
      }
  
  
  }
  </code></pre>
  
  <p>Manifest:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="info.androidhive.slidingmenu"
      android:versionCode="1"
      android:versionName="1.0" &gt;
  
      &lt;uses-sdk
          android:minSdkVersion="11"
          android:targetSdkVersion="17" /&gt;
  
      &lt;application
          android:allowBackup="true"
          android:icon="@drawable/ic_launcher"
          android:label="@string/app_name"
          android:theme="@style/AppTheme" &gt;
          &lt;activity
              android:name="info.androidhive.slidingmenu.MainActivity"
              android:label="@string/app_name" &gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
  
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
          &lt;activity android:name=".Fragment_2" &gt;
          &lt;/activity&gt;
  
      &lt;/application&gt;
  
  &lt;/manifest&gt;
  </code></pre>