Java tutorial
/* * Copyright 2017 lizhaotailang * * 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.pagenews.zhihudaily.homepage; import android.content.Context; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.design.widget.FloatingActionButton; import android.support.design.widget.TabLayout; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.view.ViewPager; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import com.pagenews.zhihudaily.R; import com.pagenews.zhihudaily.adapter.MainPagerAdapter; import java.util.Random; /** * Created by Lizhaotailang on 2016/8/23. */ public class MainFragment extends Fragment { private Context context; private MainPagerAdapter adapter; private TabLayout tabLayout; private ZhihuDailyFragment zhihuDailyFragment; private GuokrFragment guokrFragment; private DoubanMomentFragment doubanMomentFragment; private ZhihuDailyPresenter zhihuDailyPresenter; private GuokrPresenter guokrPresenter; private DoubanMomentPresenter doubanMomentPresenter; public MainFragment() { } public static MainFragment newInstance() { return new MainFragment(); } @Override public void onAttach(Context context) { super.onAttach(context); } @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); this.context = getActivity(); if (savedInstanceState != null) { FragmentManager manager = getChildFragmentManager(); zhihuDailyFragment = (ZhihuDailyFragment) manager.getFragment(savedInstanceState, "zhihu"); guokrFragment = (GuokrFragment) manager.getFragment(savedInstanceState, "guokr"); doubanMomentFragment = (DoubanMomentFragment) manager.getFragment(savedInstanceState, "douban"); } else { zhihuDailyFragment = ZhihuDailyFragment.newInstance(); guokrFragment = GuokrFragment.newInstance(); doubanMomentFragment = DoubanMomentFragment.newInstance(); } zhihuDailyPresenter = new ZhihuDailyPresenter(context, zhihuDailyFragment); guokrPresenter = new GuokrPresenter(context, guokrFragment); doubanMomentPresenter = new DoubanMomentPresenter(context, doubanMomentFragment); } @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_main, container, false); initViews(view); setHasOptionsMenu(true); // tab layout???fab tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() { @Override public void onTabSelected(TabLayout.Tab tab) { FloatingActionButton fab = (FloatingActionButton) getActivity().findViewById(R.id.fab); if (tab.getPosition() == 1) { fab.hide(); } else { fab.show(); } } @Override public void onTabUnselected(TabLayout.Tab tab) { } @Override public void onTabReselected(TabLayout.Tab tab) { } }); return view; } private void initViews(View view) { tabLayout = (TabLayout) view.findViewById(R.id.tab_layout); ViewPager viewPager = (ViewPager) view.findViewById(R.id.view_pager); viewPager.setOffscreenPageLimit(3); adapter = new MainPagerAdapter(getChildFragmentManager(), context, zhihuDailyFragment, guokrFragment, doubanMomentFragment); viewPager.setAdapter(adapter); tabLayout.setupWithViewPager(viewPager); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { super.onCreateOptionsMenu(menu, inflater); inflater.inflate(R.menu.main, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { int id = item.getItemId(); if (id == R.id.action_feel_lucky) { feelLucky(); } return true; } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); FragmentManager manager = getChildFragmentManager(); manager.putFragment(outState, "zhihu", zhihuDailyFragment); manager.putFragment(outState, "guokr", guokrFragment); manager.putFragment(outState, "douban", doubanMomentFragment); } public void feelLucky() { Random random = new Random(); int type = random.nextInt(3); switch (type) { case 0: zhihuDailyPresenter.feelLucky(); break; case 1: guokrPresenter.feelLucky(); break; default: doubanMomentPresenter.feelLucky(); break; } } public MainPagerAdapter getAdapter() { return adapter; } }