| package com.example.android.horizontalpaging; |
| |
| import java.util.Locale; |
| |
| import android.app.ActionBar; |
| import android.app.FragmentTransaction; |
| import android.os.Bundle; |
| import android.support.v4.app.Fragment; |
| import android.support.v4.app.FragmentActivity; |
| import android.support.v4.app.FragmentManager; |
| import android.support.v4.app.FragmentPagerAdapter; |
| import android.support.v4.app.NavUtils; |
| import android.support.v4.view.ViewPager; |
| import android.view.Gravity; |
| import android.view.LayoutInflater; |
| import android.view.Menu; |
| import android.view.MenuItem; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.widget.TextView; |
| |
| 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; |
| |
| /** |
| * Create the activity. Sets up an {@link ActionBar} with tabs, and then configures the |
| * {@link ViewPager} contained inside R.layout.activity_main. |
| * |
| * <p>A {@link SectionsPagerAdapter} will be instantiated to hold the different pages of |
| * fragments that are to be displayed. A |
| * {@link android.support.v4.view.ViewPager.SimpleOnPageChangeListener} will also be configured |
| * to receive callbacks when the user swipes between pages in the ViewPager. |
| * |
| * @param savedInstanceState |
| */ |
| @Override |
| protected void onCreate(Bundle savedInstanceState) { |
| super.onCreate(savedInstanceState); |
| // Load the UI from res/layout/activity_main.xml |
| setContentView(R.layout.activity_main); |
| |
| // Set up the action bar. The navigation mode is set to NAVIGATION_MODE_TABS, which will |
| // cause the ActionBar to render a set of tabs. Note that these tabs are *not* rendered |
| // by the ViewPager; additional logic is lower in this file to synchronize the ViewPager |
| // state with the tab state. (See mViewPager.setOnPageChangeListener() and onTabSelected().) |
| // BEGIN_INCLUDE (set_navigation_mode) |
| final ActionBar actionBar = getActionBar(); |
| actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS); |
| // END_INCLUDE (set_navigation_mode) |
| |
| // BEGIN_INCLUDE (setup_view_pager) |
| // 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); |
| // END_INCLUDE (setup_view_pager) |
| |
| // 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. |
| // BEGIN_INCLUDE (page_change_listener) |
| mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() { |
| @Override |
| public void onPageSelected(int position) { |
| actionBar.setSelectedNavigationItem(position); |
| } |
| }); |
| // END_INCLUDE (page_change_listener) |
| |
| // BEGIN_INCLUDE (add_tabs) |
| // 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. |
| actionBar.addTab( |
| actionBar.newTab() |
| .setText(mSectionsPagerAdapter.getPageTitle(i)) |
| .setTabListener(this)); |
| } |
| // END_INCLUDE (add_tabs) |
| } |
| |
| /** |
| * Update {@link ViewPager} after a tab has been selected in the ActionBar. |
| * |
| * @param tab Tab that was selected. |
| * @param fragmentTransaction A {@link FragmentTransaction} for queuing fragment operations to |
| * execute once this method returns. This FragmentTransaction does |
| * not support being added to the back stack. |
| */ |
| // BEGIN_INCLUDE (on_tab_selected) |
| @Override |
| public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) { |
| // When the given tab is selected, tell the ViewPager to switch to the corresponding page. |
| mViewPager.setCurrentItem(tab.getPosition()); |
| } |
| // END_INCLUDE (on_tab_selected) |
| |
| /** |
| * Unused. Required for {@link ActionBar.TabListener}. |
| */ |
| @Override |
| public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) { |
| } |
| |
| /** |
| * Unused. Required for {@link ActionBar.TabListener}. |
| */ |
| @Override |
| public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) { |
| } |
| |
| // BEGIN_INCLUDE (fragment_pager_adapter) |
| /** |
| * A {@link FragmentPagerAdapter} that returns a fragment corresponding to |
| * one of the sections/tabs/pages. This provides the data for the {@link ViewPager}. |
| */ |
| public class SectionsPagerAdapter extends FragmentPagerAdapter { |
| // END_INCLUDE (fragment_pager_adapter) |
| |
| public SectionsPagerAdapter(FragmentManager fm) { |
| super(fm); |
| } |
| |
| // BEGIN_INCLUDE (fragment_pager_adapter_getitem) |
| /** |
| * Get fragment corresponding to a specific position. This will be used to populate the |
| * contents of the {@link ViewPager}. |
| * |
| * @param position Position to fetch fragment for. |
| * @return Fragment for specified position. |
| */ |
| @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 = new DummySectionFragment(); |
| Bundle args = new Bundle(); |
| args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, position + 1); |
| fragment.setArguments(args); |
| return fragment; |
| } |
| // END_INCLUDE (fragment_pager_adapter_getitem) |
| |
| // BEGIN_INCLUDE (fragment_pager_adapter_getcount) |
| /** |
| * Get number of pages the {@link ViewPager} should render. |
| * |
| * @return Number of fragments to be rendered as pages. |
| */ |
| @Override |
| public int getCount() { |
| // Show 3 total pages. |
| return 3; |
| } |
| // END_INCLUDE (fragment_pager_adapter_getcount) |
| |
| // BEGIN_INCLUDE (fragment_pager_adapter_getpagetitle) |
| /** |
| * Get title for each of the pages. This will be displayed on each of the tabs. |
| * |
| * @param position Page to fetch title for. |
| * @return Title for specified page. |
| */ |
| @Override |
| public CharSequence getPageTitle(int position) { |
| Locale l = Locale.getDefault(); |
| switch (position) { |
| case 0: |
| return getString(R.string.title_section1).toUpperCase(l); |
| case 1: |
| return getString(R.string.title_section2).toUpperCase(l); |
| case 2: |
| return getString(R.string.title_section3).toUpperCase(l); |
| } |
| return null; |
| } |
| // END_INCLUDE (fragment_pager_adapter_getpagetitle) |
| } |
| |
| /** |
| * A dummy fragment representing a section of the app, but that simply displays dummy text. |
| * This would be replaced with your application's content. |
| */ |
| public static class DummySectionFragment extends Fragment { |
| /** |
| * The fragment argument representing the section number for this |
| * fragment. |
| */ |
| public static final String ARG_SECTION_NUMBER = "section_number"; |
| |
| public DummySectionFragment() { |
| } |
| |
| @Override |
| public View onCreateView(LayoutInflater inflater, ViewGroup container, |
| Bundle savedInstanceState) { |
| View rootView = inflater.inflate(R.layout.fragment_main_dummy, container, false); |
| TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label); |
| dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER))); |
| return rootView; |
| } |
| } |
| |
| } |