我在Activity_Homescreen中有一个视图寻呼机，并设置为FragmentPagerAdapter。 activity有4个选项卡，寻呼机适配器使用相同的片段用于前三个选项卡，另一个片段用于选项卡布局中的最后一个选项卡。初始3个选项卡的片段有两个片段（映射和回收器视图）嵌套在那片段里面。
最初，当我使用应用时，片段正确加载，即，当我从 TAB 1 - > TAB 2 - ＆gt;
如果有人能够尽快发布解决方案，那就太棒了。谢谢。
Activity_Homescreen.java
private Toolbar toolbar;
private DrawerLayout drawerLayout;
private TabLayout tabLayout;
private SearchView searchView;
private boolean searchSubmitted = false;
private NetworkInfo activeNetworkInfo;
private Homescreen_Pojo pojoInstance = Homescreen_Pojo.getInstance();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_homescreen);
ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
pojoInstance.setActiveNetworkInfo(activeNetworkInfo);
pojoInstance.setAdvancedSearchSubmitted(false);
pojoInstance.setSearchSubmitted(false);
setupToolbar();
setupTabLayout();
setupNavigationDrawer();
setupNavigationItems();
setupViewPager();
}
@Override
public void onPostCreate(Bundle savedInstanceState, PersistableBundle persistentState) {
super.onPostCreate(savedInstanceState, persistentState);
}
public void setupToolbar() {
toolbar = (Toolbar) findViewById(R.id.toolBar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
toolbar.setLogo(R.drawable.header_logo);
getSupportActionBar().setDisplayShowTitleEnabled(false);
}
private void setupNavigationDrawer() {
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle drawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.app_name, R.string.app_name);
drawerLayout.setDrawerListener(drawerToggle);
drawerToggle.syncState();
}
private void setupNavigationItems() {
final NavigationView navigationView = (NavigationView) findViewById(R.id.navigation_view);
TextView userNameCtrl = (TextView) navigationView.findViewById(R.id.navigation_userName);
ImageView userImageCtrl = (ImageView) navigationView.findViewById(R.id.navigation_userImage);
String userName = UserCredentials.getInstance().getUserName();
String userPhotoUrl = UserCredentials.getInstance().getUserPhotoUrl();
if (userName != null && userPhotoUrl != (null)) {
userNameCtrl.setText(userName);
new LoadImage(userImageCtrl).execute(userPhotoUrl);
}
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
CharSequence menuItemTitle = menuItem.getTitle();
if (Objects.equals(menuItemTitle, "Rate App")) {
final String appPackageName = getPackageName();
try {
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));
} catch (android.content.ActivityNotFoundException anfe) {
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/details?id=" + appPackageName)));
}
} else {
Activity_Login.integration.logout();
Intent intent = new Intent(getApplicationContext(), Activity_Login.class);
startActivity(intent);
}
drawerLayout.closeDrawers();
return true;
}
});
}
private void setupTabLayout() {
tabLayout = (TabLayout) findViewById(R.id.tabLayout);
tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
tabLayout.setTabMode(TabLayout.MODE_FIXED);
tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.near_me_hover).setTag(1));
tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.all_hostels).setTag(2));
tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.top_five).setTag(3));
tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.advanced_search).setTag(4));
}
private void setupViewPager() {
PagerAdapter pagerAdapter = new PagerAdapter(getSupportFragmentManager());
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
viewPager.setOffscreenPageLimit(1);
viewPager.setAdapter(pagerAdapter);
pojoInstance.setViewPager(viewPager);
}
public boolean isInternetConnected() {
boolean connection = true;
activeNetworkInfo = pojoInstance.getActiveNetworkInfo();
if (activeNetworkInfo == null || !activeNetworkInfo.isConnected()) {
connection = false;
}
return connection;
}
@Override
protected void onResume() {
final ViewPager viewPager = pojoInstance.getViewPager();
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
switch (tab.getPosition()) {
case 0:
viewPager.setCurrentItem(tab.getPosition());
tab.setIcon(R.drawable.near_me_hover);
break;
case 1:
viewPager.setCurrentItem(tab.getPosition());
tab.setIcon(R.drawable.all_hostels_hover);
break;
case 2:
viewPager.setCurrentItem(tab.getPosition());
tab.setIcon(R.drawable.top_five_hover);
break;
case 3:
viewPager.setCurrentItem(tab.getPosition());
tab.setIcon(R.drawable.advanced_search_hover);
break;
}
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
switch (tab.getPosition()) {
case 0:
tab.setIcon(R.drawable.near_me);
break;
case 1:
tab.setIcon(R.drawable.all_hostels);
break;
case 2:
tab.setIcon(R.drawable.top_five);
break;
case 3:
tab.setIcon(R.drawable.advanced_search);
break;
}
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
tabLayout.getTabAt(position).select();
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
super.onResume();
}
public void infoClick(MenuItem menuItem) {
AlertDialog.Builder builder = new AlertDialog.Builder(Activity_HomeScreen.this);
LayoutInflater inflater = LayoutInflater.from(getApplication());
View infoView = inflater.inflate(R.layout.homescreen_toolbar_info, null);
builder.setView(infoView);
builder.setCancelable(true);
builder.setIcon(R.drawable.launcher_icon);
builder.setNeutralButton("Ok, got it", null);
builder.show();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_home_screen, menu);
final MenuItem searchItem = menu.findItem(R.id.search);
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
searchView = null;
if (searchItem != null) {
searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
}
if (searchView != null) {
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setIconifiedByDefault(true);
searchView.setSubmitButtonEnabled(false);
searchView.setQueryHint("Place / Hostel Name");
searchView.setOnSearchClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
toolbar.setBackgroundColor(R.drawable.header_searchview);
}
});
searchView.setOnCloseListener(new SearchView.OnCloseListener() {
@Override
public boolean onClose() {
searchView.onActionViewCollapsed();
toolbar.setBackgroundResource(R.drawable.header_bg);
return true;
}
});
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
Homescreen_Pojo.getInstance().setUserQuery(query);
pojoInstance.setSearchSubmitted(true);
Intent intent = new Intent(Activity_HomeScreen.this, Activity_SimpleSearchView.class);
startActivity(intent);
return true;
}
@Override
public boolean onQueryTextChange(String newText) {
return false;
}
});
}
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
return id == R.id.action_settings || super.onOptionsItemSelected(item);
}
}
PagerAdapter.java
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new Fragment_Tabs_CommonUI();
case 1:
return new Fragment_Tabs_CommonUI();
case 2:
return new Fragment_Tabs_CommonUI();
case 3:
return new Fragment_Tab4();
}
return null;
}
@Override
public int getCount() {
return 4;
}
}
Fragment for first 3 tabs
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
int num = Homescreen_Pojo.getInstance().getViewPager().getCurrentItem();
tabView = inflater.inflate(R.layout.tab_common_ui, container, false);
if (Homescreen_Pojo.getInstance().isSearchSubmitted()) {
setUserVisibleHint(true);
}
return tabView;
}
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
int number = Homescreen_Pojo.getInstance().getViewPager().getCurrentItem();
if (isVisibleToUser) {
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getActivity());
if (status == ConnectionResult.SUCCESS) {
FragmentManager fragmentManager = getChildFragmentManager();
MapFragment mapFragment = new MapFragment();
CardList_Fragment listFragment = new CardList_Fragment();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.add(R.id.map_container, mapFragment);
transaction.add(R.id.cardlist_container, listFragment);
transaction.commitAllowingStateLoss();
fragmentManager.executePendingTransactions();
} else {
Snackbar.make(tabView, "GooglePlay Service not available !!", Snackbar.LENGTH_LONG).show();
}
}
}
}
MapFragment
public MapFragment() {
super();
}
@Override
public View onCreateView(LayoutInflater arg0, ViewGroup arg1, Bundle arg2) {
View v = super.onCreateView(arg0, arg1, arg2);
initializeMap();
return v;
}
private void initializeMap() {
GPS_Tracker gpsTracker = new GPS_Tracker(getActivity());
googleMap = getMap();
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
googleMap.setMyLocationEnabled(true);
googleMap.getUiSettings().setZoomControlsEnabled(true);
googleMap.getUiSettings().setMyLocationButtonEnabled(true);
googleMap.getUiSettings().setCompassEnabled(true);
googleMap.getUiSettings().setRotateGesturesEnabled(true);
googleMap.getUiSettings().setZoomGesturesEnabled(true);
googleMap.getUiSettings().setScrollGesturesEnabled(true);
googleMap.getUiSettings().setTiltGesturesEnabled(true);
LatLng technoparkLocation = new LatLng(8.55765, 76.88092);
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(technoparkLocation, 15));
double userLatitude = gpsTracker.getLatitude();
double userLongitude = gpsTracker.getLongitude();
pojoInstance.setUserLatitude(userLatitude);
pojoInstance.setUserLongitude(userLongitude);
LatLng userLocation = new LatLng(userLatitude, userLongitude);
googleMap.addMarker(new MarkerOptions().position(userLocation).title("User Location").icon(BitmapDescriptorFactory.fromResource(R.drawable.map_userlocation)));
}
public void addMarkers(final ArrayList<Hostel> hostelList, Context mContext) {
this.mapContext = mContext;
for (Hostel hostel : hostelList) {
Marker marker;
if (hostel.getHostelType().equals("gents")) {
marker = googleMap.addMarker(new MarkerOptions().position(new LatLng(hostel.getHostelLatitude(), hostel.getHostelLongitude())).icon(BitmapDescriptorFactory.fromResource(R.drawable.map_marker_gents)).title(hostel.getName()).snippet(hostel.getPlace()));
} else if (hostel.getHostelType().equals("ladies")) {
marker = googleMap.addMarker(new MarkerOptions().position(new LatLng(hostel.getHostelLatitude(), hostel.getHostelLongitude())).icon(BitmapDescriptorFactory.fromResource(R.drawable.map_marker_ladies)).title(hostel.getName()).snippet(hostel.getPlace()));
} else {
marker = googleMap.addMarker(new MarkerOptions().position(new LatLng(hostel.getHostelLatitude(), hostel.getHostelLongitude())).icon(BitmapDescriptorFactory.fromResource(R.drawable.map_marker_family)).title(hostel.getName()).snippet(hostel.getPlace()));
}
String markerTitle = marker.getTitle();
infoWindowHashMap.put(markerTitle, hostel);
showHostelInMap.put(markerTitle, marker);
pojoInstance.setInfoWindowHashMap(infoWindowHashMap);
pojoInstance.setShowInMap(showHostelInMap);
}
googleMap.setOnInfoWindowClickListener(new GoogleMap.OnInfoWindowClickListener() {
@Override
public void onInfoWindowClick(Marker marker) {
if (infoWindowHashMap.containsKey(marker.getTitle())) {
Hostel hostel = infoWindowHashMap.get(marker.getTitle());
Intent hostelIntent = new Intent(mapContext, Activity_HostelDetails.class).setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
hostelIntent.putExtra("hostelObj", hostel);
mapContext.startActivity(hostelIntent);
}
}
});
}
public void highlightMarker(Hostel hostel) {
if (pojoInstance.getInfoWindowHashMap().containsValue(hostel)) {
String title = hostel.getName();
HashMap<String, Marker> hashMap = pojoInstance.getShowInMap();
if (hashMap.containsKey(title)) {
Marker marker = (Marker) hashMap.get(title);
googleMap.animateCamera(CameraUpdateFactory.newLatLng(marker.getPosition()), 250, null);
marker.showInfoWindow();
}
}
}
}
RecylerView Fragment
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.cardlist_fragment, container, false);
RecyclerView recyclerView = (RecyclerView) rootView.findViewById(R.id.rv);
ImageView noResults = (ImageView) rootView.findViewById(R.id.no_results);
TextView noResultsText = (TextView) rootView.findViewById(R.id.no_results_text);
recyclerView.setVisibility(View.VISIBLE);
noResults.setVisibility(View.GONE);
noResultsText.setVisibility(View.GONE);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
Homescreen_Pojo.getInstance().setRecyclerView(recyclerView);
Homescreen_Pojo.getInstance().setNoResultsText(noResultsText);
Homescreen_Pojo.getInstance().setNoResultsImage(noResults);
HostelDetailsManager manager = new HostelDetailsManager(getContext(), recyclerView);
manager.jsonRequest(APIcontroller.getInstance().getURL());
return rootView;
}
}