Java tutorial
/* * Copyright (C) 2012 Juhani Lehtimaki * * 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.androiduipatterns.smashingandroidui.examples.tabs; 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.Gravity; import android.view.LayoutInflater; import android.view.Menu; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import com.androiduipatterns.smashingandroidui.examples.R; public class TabsExampleActivity 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 public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_tabs_example); // 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 action bar. final ActionBar actionBar = getActionBar(); actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS); // 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 // listener for when this tab is selected. actionBar .addTab(actionBar.newTab().setText(mSectionsPagerAdapter.getPageTitle(i)).setTabListener(this)); } } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.activity_tabs_example, menu); return true; } @Override public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) { } @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 onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) { } /** * A {@link FragmentPagerAdapter} that returns a fragment corresponding to one of the primary * sections of the app. */ public class SectionsPagerAdapter extends FragmentPagerAdapter { public SectionsPagerAdapter(FragmentManager fm) { super(fm); } @Override public Fragment getItem(int i) { Fragment fragment = new DummySectionFragment(); Bundle args = new Bundle(); args.putInt(DummySectionFragment.ARG_SECTION_NUMBER, i + 1); fragment.setArguments(args); return fragment; } @Override public int getCount() { return 3; } @Override public CharSequence getPageTitle(int position) { switch (position) { case 0: return getString(R.string.title_section1).toUpperCase(); case 1: return getString(R.string.title_section2).toUpperCase(); case 2: return getString(R.string.title_section3).toUpperCase(); } return null; } } /** * A dummy fragment representing a section of the app, but that simply displays dummy text. */ public static class DummySectionFragment extends Fragment { public DummySectionFragment() { } public static final String ARG_SECTION_NUMBER = "section_number"; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { TextView textView = new TextView(getActivity()); textView.setGravity(Gravity.CENTER); Bundle args = getArguments(); textView.setText(Integer.toString(args.getInt(ARG_SECTION_NUMBER))); return textView; } } }