package com.example.android.horizontalpaging;
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.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import java.util.Locale;
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 android.app.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.sample_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 android.app.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 android.app.ActionBar.TabListener}.
*/
@Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
}
/**
* Unused. Required for {@link android.app.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;
}
}
}