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I'm using the ActionBar and tab navigation with Fragments.

Each tab contain a Fragment FragmentX with a ListView, and when clicking on an item of a list FragmentX is replaced by another Fragment FragmentY with the detail of the item.

How can I set the Up button of the ActionBar to load FragmentX when I'm in FragmentY?

The doc shows that the navigation should be done between Activities, but the ActionBar's navigation tabs allow to navigate between Fragments, not Activities.

What am I missing?

public class MainActivity extends FragmentActivity implements
ActionBar.TabListener {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide
     * fragments for each of the sections. We use a
     * {@link android.support.v4.app.FragmentPagerAdapter} derivative, which
     * will keep every loaded fragment in memory. If this becomes too memory
     * intensive, it may be best to switch to a
     * {@link android.support.v4.app.FragmentStatePagerAdapter}.
     */
    SectionsPagerAdapter mSectionsPagerAdapter;

    /**
     * The {@link ViewPager} that will host the section contents.
     */
    ViewPager mViewPager;

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

        // Set up the action bar.
        final ActionBar actionBar = getActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        // Create the adapter that will return a fragment for each of the three
        // primary sections of the app.
        mSectionsPagerAdapter = new SectionsPagerAdapter(
                getSupportFragmentManager());

        // Set up the ViewPager with the sections adapter.
        mViewPager = (ViewPager) findViewById(R.id.pager);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        // When swiping between different sections, select the corresponding
        // tab. We can also use ActionBar.Tab#select() to do this if we have
        // a reference to the Tab.
        mViewPager
        .setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                actionBar.setSelectedNavigationItem(position);
            }
        });

        // For each of the sections in the app, add a tab to the action bar.
        for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
            // Create a tab with text corresponding to the page title defined by
            // the adapter. Also specify this Activity object, which implements
            // the TabListener interface, as the callback (listener) for when
            // this tab is selected.

            LinearLayout view = (LinearLayout) getLayoutInflater().inflate(R.layout.tab, null);

            ImageView icon = (ImageView) view.findViewById(R.id.icon);
            icon.setImageResource(tabIconList[i]);

            TextView title = (TextView) view.findViewById(R.id.title);
            title.setText(tabTitleList[i]);


            actionBar.addTab(actionBar.newTab()
                    .setCustomView(view)
                    .setTabListener(this));
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
        // When the given tab is selected, switch to the corresponding page in
        // the ViewPager.
        mViewPager.setCurrentItem(tab.getPosition());
    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
    }

    @Override
    public void onTabReselected(ActionBar.Tab tab,
            FragmentTransaction fragmentTransaction) {
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
     * one of the sections/tabs/pages.
     */
    public class SectionsPagerAdapter extends FragmentPagerAdapter {

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a DummySectionFragment (defined as a static inner class
            // below) with the page number as its lone argument.


            Fragment fragment = null;

            switch(position){
            case 0:
                fragment = new MyListFragment1();
                break;
            case 1:
                fragment = new MyListFragment2();
                break;
            case 2:
                fragment = new MyListFragment3();
                break;
            default: fragment = new MyListFragment1();

            }

            return fragment;

        }

        @Override
        public int getCount() {
            // Show 3 total pages.
            return 3;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            Locale l = Locale.getDefault();
            switch (position) {
            case 0:
                return getString(R.string.title1).toUpperCase(l);
            case 1:
                return getString(R.string.title2).toUpperCase(l);
            case 2:
                return getString(R.string.title3).toUpperCase(l);
            }
            return null;
        }
    }

}
jul
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2 Answers2

0

Active up navigation when you load FragmentY. Then intercept up navigation on onOptionsItemSelected, just popup the backstack and launch your FragmentX.

I've done a rapid search on SO and i found this, wich inspired me.

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JJ86
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0

I didn't use the ActionBar in the end. Too many constraints (I had another issue and I wanted to add a View above the ActionBar, which seemed complicated).

It was much simpler doing my own layout from scratch.

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jul
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