I have implement an app that has a fragment system exactly like Instagram.
When I select a tab in bottom tab the fragment is replaced in the container.
My problem is when I go to another fragment and get back to this fragment the data is reloading and the fragment recreating.
I have searched and no answer helped me. I see this answer and I think it's correct, but I don't know how to use it and what FragmentMetaData is.
This is my main activity:
public class MainActivity extends FragmentActivity {
//set this tablayout to puplic static, so we can access this from othere fragment
public static TabLayout tabLayout_bottom;
Fragment fragmentHome = new FragmentHome();
Fragment fragmentSearch = new FragmentSearch();
Fragment fragmentLikes = new FragmentLikes();
Fragment fragmentProfile = new FragmentProfile();
//use fragment manager to manage fragment
private FragmentManager fragmentManager = getSupportFragmentManager();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//set current fragment to FragmentHome when activity start
this.getSupportFragmentManager().beginTransaction().replace(R.id.container, fragmentHome).commit();
tabLayout_bottom = (TabLayout) findViewById(R.id.tabs_bottom_home);
//this code change color of statusbar if current android version is more then lollipop
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
getWindow().setStatusBarColor(getResources().getColor(R.color.colorPrimaryDark));
}
createTabIcons_bottom();
//this method change the language of hole app. so if user change his device language, the app not changing
//if you want persian change "en" to "fa"
String languageToLoad = "en"; // your language
Locale locale = new Locale(languageToLoad);
Locale.setDefault(locale);
Configuration config = new Configuration();
config.locale = locale;
}
private void createTabIcons_bottom() {
//this set icon for each tab
tabLayout_bottom.addTab(tabLayout_bottom.newTab().setIcon(R.drawable.ic_home_black_24dp));
tabLayout_bottom.addTab(tabLayout_bottom.newTab().setIcon(R.drawable.ic_search_black_24dp));
tabLayout_bottom.addTab(tabLayout_bottom.newTab().setIcon(R.drawable.ic_add_box_black_24dp));
tabLayout_bottom.addTab(tabLayout_bottom.newTab().setIcon(R.drawable.ic_favorite_black_24dp));
tabLayout_bottom.addTab(tabLayout_bottom.newTab().setIcon(R.drawable.ic_person_black_24dp));
//set color for each icon
tabLayout_bottom.getTabAt(0).getIcon().setColorFilter(getResources().getColor(R.color.colorAccent), PorterDuff.Mode.SRC_IN);
tabLayout_bottom.getTabAt(1).getIcon().setColorFilter(getResources().getColor(R.color.colorPrimaryDark), PorterDuff.Mode.SRC_IN);
tabLayout_bottom.getTabAt(2).getIcon().setColorFilter(getResources().getColor(R.color.colorPrimaryDark), PorterDuff.Mode.SRC_IN);
tabLayout_bottom.getTabAt(3).getIcon().setColorFilter(getResources().getColor(R.color.colorPrimaryDark), PorterDuff.Mode.SRC_IN);
tabLayout_bottom.getTabAt(4).getIcon().setColorFilter(getResources().getColor(R.color.colorPrimaryDark), PorterDuff.Mode.SRC_IN);
tabLayout_bottom.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
//set color when tab selected
int tabIconColor = ContextCompat.getColor(getApplicationContext(), R.color.colorAccent);
tab.getIcon().setColorFilter(tabIconColor, PorterDuff.Mode.SRC_IN);
if (tab.getPosition() == 0) {
GotoFragmentHome();
}
else if (tab.getPosition() == 1) {
GotoFragmentSearch();
}
else if (tab.getPosition() == 2) {
GotoActivityAdd();
}
else if (tab.getPosition() == 3) {
GotoFragmetnLikes();
}
else if (tab.getPosition() == 4) {
GotoFragmetnProfile();
}
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
//set color if tab unselect
int tabIconColor = ContextCompat.getColor(getApplicationContext(), R.color.colorPrimaryDark);
tab.getIcon().setColorFilter(tabIconColor, PorterDuff.Mode.SRC_IN);
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
//each method is for a fragment that use when a tab seleted
//the addToBackStack method hold that fragment in a stack so when back pressed, geting back to last fragment
public void GotoFragmentHome() {
fragmentManager.beginTransaction().replace(R.id.container, fragmentHome).addToBackStack("home").commit();
}
public void GotoFragmentSearch() {
fragmentManager.beginTransaction().replace(R.id.container, fragmentSearch).addToBackStack("search").commit();
}
public void GotoActivityAdd() {
startActivity(new Intent(getApplicationContext(), ActivityAdd.class));
}
public void GotoFragmetnLikes() {
fragmentManager.beginTransaction().replace(R.id.container, fragmentLikes).addToBackStack("likes").commit();
}
public void GotoFragmetnProfile() {
fragmentManager.beginTransaction().replace(R.id.container, fragmentProfile).addToBackStack("profile").commit();
}
#Override
public void onBackPressed() {
//this says that if no fragment was in stack, so exit app
if (fragmentManager.getBackStackEntryCount() > 0) {
fragmentManager.popBackStack();
fragmentManager.popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
else {
//exit hole app
moveTaskToBack(true);
return;
}
}
}
And this is one of my fragments:
public class FragmentSearch extends Fragment {
private LinearLayout toolbar_search;
public FragmentSearch() {
// Required empty public constructor
}
View rootView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
rootView = inflater.inflate(R.layout.fragment_search, container, false);
//select search tab if user back to this fragment
MainActivity.tabLayout_bottom.getTabAt(1).select();
//save current tab position in sharedpreferance. so if uer get back from Add Activity, select last tab
int tabselected=MainActivity.tabLayout_bottom.getSelectedTabPosition();
SharedPreferences.Editor editor=getActivity().getSharedPreferences("selectedtab", Context.MODE_PRIVATE).edit();
editor.putInt("selectedtab",tabselected);
editor.commit();
toolbar_search=(LinearLayout) rootView.findViewById(R.id.toolbar_in_searchfragment);
toolbar_search.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
startActivity(new Intent(getActivity(), ActivitySearch.class));
}
});
return rootView;
}
}
If somebody help me I'd be grateful. I see the savedInstanceState in some answers but that has not worked for me.
Related
I make a simple android App which have a Login activity and one fragment(BottomSheetDialogFragment) I am trying to add multiple languages through the fragment (which have multiple buttons) to main activity(Login Activity) but its not working here below the code can some one help me please?
Login Activity
public class LoginActivity extends AppCompatActivity {
private ActivityLoginBinding binding;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityLoginBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
binding.button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
bottomnav bottomnav=new bottomnav();
bottomnav.show(getSupportFragmentManager(),bottomnav.getTag());
}
});
}
}
Fragment
public class bottomnav extends BottomSheetDialogFragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view= inflater.inflate(R.layout.fragment_bottomnav, container, false);
Button urdu,hindi,arabic,eng;
eng=view.findViewById(R.id.english);
urdu=view.findViewById(R.id.urdu);
hindi=view.findViewById(R.id.hindi);
arabic=view.findViewById(R.id.arabic);
eng.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
return view;
}
private void setlocale(String language) {
Locale locale= new Locale(language);
Locale.setDefault(locale);
Configuration config = new Configuration();
config.locale = locale;
getContext().getResources().updateConfiguration(config,
getContext().getResources().getDisplayMetrics());
}
public void onClick(View v) {
switch(v.getId()) {
case R.id.english:
setlocale("");
break;
case R.id.urdu:
setlocale("ur");
break;
case R.id.hindi:
setlocale("hi");
break;
case R.id.arabic:
setlocale("ar");
break;
default:
}
}
}
Login activity
Fragment
You need to refresh the activity for the language changes to apply
in my app I have a navigationbar with three tabs, each tab is a Fragment and the bar looks like this: https://gyazo.com/5052f885effb3e0154d407b3bd8d3884 It's simply a normal navigation bar with three tabs.
So now I want to display my Interstitial ad (which I load in my MainActivity onCreate) by pressing the second tab in this case the tab which is named "Ausraster".
So I did the following: I loaded the Interstitial ad in my MainActivity onCreate like this:
public class MainActivity extends AppCompatActivity{
public InterstitialAd mInterstitialAd;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
AdRequest adRequest = new AdRequest.Builder().build();
mInterstitialAd = new InterstitialAd(MainActivity.this);
mInterstitialAd.setAdUnitId("MY ID");
mInterstitialAd.loadAd(adRequest);
}
and then I wrote the displayInterstitial method in my MainActivity:
public void displayInterstitial() {
mInterstitialAd.setAdListener(new AdListener() {
public void onAdLoaded() {
if (mInterstitialAd.isLoaded()) {
mInterstitialAd.show();
}
}
});
}
At last I wrote this line in the onCreateView of my second fragment the "Ausraster" fragment:
((MainActivity)getActivity()).displayInterstitial();
Should now actually fold everything but the problem is following: If I start the application the Interstitial Ad displays after a delay of 3 seconds without pressing on the second tab. But I want that its only display if I click on the second tab. So what can I do?
I have this problem now over a month and I would be so glad if someone can tell me why the Interstitial ad displays without pressing the second tab.
Here are all my codes, I hope you can explain it to me and sorry for my bad English :)
MainActivity:
public class MainActivity extends AppCompatActivity{
FragmentManager mFragmentManager;
FragmentTransaction mFragmentTransaction;
public InterstitialAd mInterstitialAd;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/**
*Setup the NavigationView
*/
mNavigationView = (NavigationView) findViewById(R.id.shitstuff) ;
/**
* Lets inflate the very first fragment
* Here , we are inflating the TabFragment as the first Fragment
*/
mFragmentManager = getSupportFragmentManager();
mFragmentTransaction = mFragmentManager.beginTransaction();
mFragmentTransaction.replace(R.id.containerView,new TabFragment()).commit();
AdRequest adRequest = new AdRequest.Builder().build();
mInterstitialAd = new InterstitialAd(MainActivity.this);
mInterstitialAd.setAdUnitId("MyId");
mInterstitialAd.loadAd(adRequest);
}
public void displayInterstitial() {
mInterstitialAd.setAdListener(new AdListener() {
public void onAdLoaded() {
if (mInterstitialAd.isLoaded()) {
mInterstitialAd.show();
}
}
});
}
}
TabFragment:
public class TabFragment extends Fragment {
public static TabLayout tabLayout;
public static ViewPager viewPager;
public static int int_items = 3 ;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
/**
*Inflate tab_layout and setup Views.
*/
View x = inflater.inflate(R.layout.tab_layout,null);
tabLayout = (TabLayout) x.findViewById(R.id.tabs);
viewPager = (ViewPager) x.findViewById(R.id.viewpager);
/**
*Set an Apater for the View Pager
*/
viewPager.setAdapter(new MyAdapter(getChildFragmentManager()));
/**
* Now , this is a workaround ,
* The setupWithViewPager dose't works without the runnable .
* Maybe a Support Library Bug .
*/
tabLayout.post(new Runnable() {
#Override
public void run() {
tabLayout.setupWithViewPager(viewPager);
}
});
return x;
}
class MyAdapter extends FragmentPagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
/**
* Return fragment with respect to Position .
*/
#Override
public Fragment getItem(int position)
{
if(position == 0){
return new KommentareFragment();
}
if(position == 1){
return new AusrasterFragment();
}
if(position == 2){
return new LustigesFragment();
}
return null;
}
#Override
public int getCount() {
return int_items;
}
/**
* This method returns the title of the tab according to the position.
*/
#Override
public CharSequence getPageTitle(int position) {
switch (position){
case 0 :
return "Kommentare";
case 1 :
return "Ausraster";
case 2 :
return "Lustiges";
}
return null;
}
}
final public void showInterstitial(){
mInterstitialAd.setAdListener(new AdListener() {
#Override
public void onAdLoaded() {
super.onAdLoaded();
if(mInterstitialAd.isLoaded()){
mInterstitialAd.show();
}
}
#Override
public void onAdClosed() {
}
});
}
}
And at last my secondFragment:
public class AusrasterFragment extends Fragment{
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView=inflater.inflate(R.layout.ausraster_layout,container,false);
return rootView;
}
The ViewPager loads other off-screen fragments in advance to make the animation look smooth when change the tab.
Because of this, the ads was getting loaded without clicking on the second tab. However, you can change the number of off screen fragments to load by using viewPager.setOffscreenPageLimit but its default and minimum value is 1. If you set it to 1, your second tab will be created in advance but not the third one.
To load ads on selection of second tab, you have to use ViewPager's pageChangeListener and check if second tab got selected, show the Ads.
viewPager.setOnPageChangeListener(new OnPageChangeListener() {
public void onPageScrollStateChanged(int state) {}
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {}
public void onPageSelected(int position) {
if(position == 1)
displayInterstitial();
}
});
And don't forget to remove ((MainActivity)getActivity()).displayInterstitial(); from the fragment.
I am building an OpenGL live wallpaper. I decided to have a Navigation Drawer in my main activity since there are a lot of features the user will have access to.
The problem/issue
If I press the "hardware" back button to normally close an app the initial fragment that is shown just refreshes and the app never closes. If I hit the home button and go back to the app everything is a black screen. I've searched all throughout Google thinking that maybe I wasn't destroying the MainActivity properly or for a way to terminate a fragment. I've tried calling finish() in the main activity's onDestroy method. I've tried utilizing the remove method from fragment manager in each fragments onDetach method per posts that I've found online. Nothing has worked. I'm stumped. I've set debug points in the main activity on the onDestroy method and on the fragments onDetach method with no error being produced or any information being given. At this point I am clueless. Here's my MainActivity class.
public class MainActivity extends AppCompatActivity implements OnNavigationItemSelectedListener, OnPostSelectedListener{
FragmentManager mFragmentManager;
FragmentTransaction mFragmentTransaction;
TextView usrTag, tagrEmail;
CircleImageView tagrPic;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
mFragmentManager = getSupportFragmentManager();
mFragmentTransaction = mFragmentManager.beginTransaction();
mFragmentTransaction.add(R.id.cLMain, new PreviewFragment()).addToBackStack("PreviewFragment").commit();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
View header = navigationView.getHeaderView(0);
usrTag = (TextView)header.findViewById(R.id.usrName);
tagrEmail = (TextView)header.findViewById(R.id.usrEmail);
tagrPic = (CircleImageView)header.findViewById(R.id.usrImg);
Log.i("MainActivity: ", "User Photo: " + getProfilePic(this));
usrTag.setText(getUserName(getBaseContext()));
tagrEmail.setText(getUserEmail(getBaseContext()));
GlideUtils.loadProfileIcon(getProfilePic(getBaseContext()), tagrPic);
}
#Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
Fragment fragment = null;
Class fragmentClass = null;
int id = item.getItemId();
if (id == R.id.nav_home) {
fragmentClass = PreviewFragment.class;
} else if (id == R.id.nav_custom) {
startCustomLabelCreator();
} else if (id == R.id.nav_mylabels) {
} else if (id == R.id.nav_commLabels) {
fragmentClass = PostsFragment.class;
} else if (id == R.id.nav_share) {
} else if (id == R.id.nav_send) {
}
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.cLMain, fragment).commit();
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
public void startCustomLabelCreator(){
Intent cLC = new Intent(getBaseContext(), CreateLabel.class);
startActivity(cLC);
}
#Override
public void onPostComment(String postKey) {
}
#Override
public void onPostLike(String postKey) {
}
#Override
public void onPhotoSelected(String photoUrl) {
}
#Override
protected void onDestroy() {
super.onDestroy();
finish();
}
}
My Fragments
public class PostsFragment extends Fragment implements ConfirmSelectedPhotoListener{
public static final String TAG = "PostsFragment";
private static final String KEY_LAYOUT_POSITION = "layoutPosition";
private int mRecyclerViewPosition = 0;
private OnPostSelectedListener mListener;
private RecyclerView mRecyclerView;
private RecyclerView.Adapter<PostViewHolder> mAdapter;
public PostsFragment() {
// Required empty public constructor
}
public static PostsFragment newInstance() {
PostsFragment fragment = new PostsFragment();
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_posts, container, false);
rootView.setTag(TAG);
mRecyclerView = (RecyclerView) rootView.findViewById(R.id.my_recycler_view);
return rootView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity());
linearLayoutManager.setReverseLayout(true);
linearLayoutManager.setStackFromEnd(true);
mRecyclerView.setLayoutManager(linearLayoutManager);
Log.d(TAG, "Restoring recycler view position (all): " + mRecyclerViewPosition);
Query allPostsQuery = FirebaseUtil.getPostsRef();
mAdapter = getFirebaseRecyclerAdapter(allPostsQuery);
mAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
#Override
public void onItemRangeInserted(int positionStart, int itemCount) {
super.onItemRangeInserted(positionStart, itemCount);
// TODO: Refresh feed view.
}
});
mRecyclerView.setAdapter(mAdapter);
}
private FirebaseRecyclerAdapter<Post, PostViewHolder> getFirebaseRecyclerAdapter(Query query) {
return new FirebaseRecyclerAdapter<Post, PostViewHolder>(
Post.class, R.layout.post_item, PostViewHolder.class, query) {
#Override
public void populateViewHolder(final PostViewHolder postViewHolder,
final Post post, final int position) {
setupPost(postViewHolder, post, position, null);
}
#Override
public void onViewRecycled(PostViewHolder holder) {
super.onViewRecycled(holder);
// FirebaseUtil.getLikesRef().child(holder.mPostKey).removeEventListener(holder.mLikeListener);
}
};
}
private void setupPost(final PostViewHolder postViewHolder, final Post post, final int position, final String inPostKey) {
postViewHolder.setPhoto(post.getThumb_url());
Log.d(TAG, post.getThumb_url());
postViewHolder.setText(post.getText());
postViewHolder.setTimestamp(DateUtils.getRelativeTimeSpanString(
(long) post.getTimestamp()).toString());
final String postKey;
if (mAdapter instanceof FirebaseRecyclerAdapter) {
postKey = ((FirebaseRecyclerAdapter) mAdapter).getRef(position).getKey();
} else {
postKey = inPostKey;
}
Author author = post.getAuthor();
postViewHolder.setAuthor(author.getFull_name(), author.getUid());
postViewHolder.setIcon(author.getProfile_picture(), author.getUid());
ValueEventListener likeListener = new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
postViewHolder.setNumLikes(dataSnapshot.getChildrenCount());
if (dataSnapshot.hasChild(FirebaseUtil.getCurrentUserId())) {
postViewHolder.setLikeStatus(PostViewHolder.LikeStatus.LIKED, getActivity());
} else {
postViewHolder.setLikeStatus(PostViewHolder.LikeStatus.NOT_LIKED, getActivity());
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
};
FirebaseUtil.getLikesRef().child(postKey).addValueEventListener(likeListener);
postViewHolder.mLikeListener = likeListener;
postViewHolder.setPostClickListener(new PostViewHolder.PostClickListener() {
#Override
public void showComments() {
Log.d(TAG, "Comment position: " + position);
mListener.onPostComment(postKey);
}
#Override
public void toggleLike() {
Log.d(TAG, "Like position: " + position);
mListener.onPostLike(postKey);
}
#Override
public void savePhotoUrl() {
//mListener.onPhotoSelected(post.getFull_url());
showLabelConfirm(post.getFull_url());
}
});
}
#Override
public void onDestroy() {
super.onDestroy();
if (mAdapter != null && mAdapter instanceof FirebaseRecyclerAdapter) {
((FirebaseRecyclerAdapter) mAdapter).cleanup();
}
}
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// Save currently selected layout manager.
int recyclerViewScrollPosition = getRecyclerViewScrollPosition();
Log.d(TAG, "Recycler view scroll position: " + recyclerViewScrollPosition);
savedInstanceState.putSerializable(KEY_LAYOUT_POSITION, recyclerViewScrollPosition);
super.onSaveInstanceState(savedInstanceState);
}
private int getRecyclerViewScrollPosition() {
int scrollPosition = 0;
// TODO: Is null check necessary?
if (mRecyclerView != null && mRecyclerView.getLayoutManager() != null) {
scrollPosition = ((LinearLayoutManager) mRecyclerView.getLayoutManager())
.findFirstCompletelyVisibleItemPosition();
}
return scrollPosition;
}
#Override
public void onSelectedPhoto(String selectPhoto) {
mListener.onPhotoSelected(selectPhoto);
}
public interface OnPostSelectedListener {
void onPostComment(String postKey);
void onPostLike(String postKey);
void onPhotoSelected(String photoUrl);
}
private void showLabelConfirm(String uriBmp) {
FragmentManager fm = getFragmentManager();
PhotoDialogFragment editNameDialogFragment = PhotoDialogFragment.newInstance(uriBmp);
// SETS the target fragment for use later when sending results
editNameDialogFragment.setTargetFragment(PostsFragment.this, 300);
editNameDialogFragment.show(fm, "fragment_edit_name");
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnPostSelectedListener) {
mListener = (OnPostSelectedListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnPostSelectedListener");
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
}
Second Fragment:
public class PreviewFragment extends RajBaseFragment {
#Override
public ISurfaceRenderer createRenderer() {
return new PreviewRenderer(getContext());
}
}
Which extends:
public abstract class RajBaseFragment extends Fragment implements IDisplay, View.OnClickListener {
protected FrameLayout mLayout;
protected ISurface mRajawaliSurface;
protected ISurfaceRenderer mRenderer;
public RajBaseFragment(){
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
// Inflate the view
mLayout = (FrameLayout) inflater.inflate(getLayoutID(), container, false);
mLayout.findViewById(R.id.relative_layout_loader_container).bringToFront();
// Find the TextureView
mRajawaliSurface = (ISurface) mLayout.findViewById(R.id.rajwali_surface);
// Create the loader
mRenderer = createRenderer();
onBeforeApplyRenderer();
applyRenderer();
return mLayout;
}
protected void onBeforeApplyRenderer() {
}
protected void applyRenderer() {
mRajawaliSurface.setSurfaceRenderer(mRenderer);
}
#Override
public void onClick(View v) {
}
#Override
public void onDestroyView() {
super.onDestroyView();
if (mLayout != null)
mLayout.removeView((View) mRajawaliSurface);
}
#Override
public int getLayoutID() {
return R.layout.rajawali_textureview_fragment;
}
}
I've tried all the recommendations below so far and the primary fragment that is set in the MainActivity's onCreate method still gets refreshed/reloaded when the back button is pressed rather than the app exiting/closing.
In your onNavigationItemSelected method, you are replacing the current fragment with fragment even in cases where fragment is null, which has undefined effects. You should not do that.
One fix is to replace this code block:
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
with this one:
if (fragmentClass != null) {
fragment = fragmentClass.newInstance();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.cLMain, fragment).addToBackStack().commit();
}
(and then leave out the fragment transaction below this point).
Also, there is a call to finish in the onDestroy method, which probably is not causing the problem but should be taken out because it does not make any sense there.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
break;
}
return true;
}
replace your onOptionsItemSelected() with mine.
Don't include your first fragment into backstack.
Try to change you fragment transaction line code without addToBackStack
as below:
mFragmentTransaction.add(R.id.cLMain, new PreviewFragment()).commit();
While adding fragment with addToBackStack, this allows back
navigation for added fragment.Because of fragment in backstack,
empty(black) activity layout will be displayed.
Change onBackPressed() as below which automatically close app after if no any Fragment found in FragmentManager:
#Override
public void onBackPressed() {
if (getSupportFragmentManager().getBackStackEntryCount() == 0) {
this.finish();
} else {
getSupportFragmentManager().popBackStack();
}
}
Also you can see some similar Q/A on below links which helps you get more idea to solve your problem:
Fragment pressing back button
In Fragment on back button pressed Activity is blank
Transaction of fragments in android results in blank screen
It's solved my blank screen problem. Hope its helps you.
Try this code, hope this helps you, take necessary stuffs which are required for you. Also, try running this project in Android studio, it works.
https://github.com/asifali22/Navigation_Health/blob/master/app/src/main/java/com/thenewboston/mynavigation/MainActivity.java
When user press to back button it'll check fragment manager's backstack and if backstack entity count is bigger than 0 (this means there's a fragment in backstack) it'll popBackStack else it'll finish activity.
If you add your initial fragment to backstack, when user press back button they'll see a blank screen.
Also when you init your activity if you need to put a fragment it's a best practice to check if saved instance state is null. Here i modified some part of your code.
if(savedInstanceState == null){
mFragmentManager = getSupportFragmentManager();
mFragmentTransaction = mFragmentManager.beginTransaction();
mFragmentTransaction.add(R.id.cLMain, new PreviewFragment()).commit();
}
I hope this'll help you. If you still have problem let me know.
Good luck.
create subclass for ISurface and override onKeyDown method like this
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
Log.e("Custom View", "onKeyDown");
//return super.onKeyDown(keyCode, event);
return false;
}
Could be related with the lifecycle...
Try using GLSurfaceView. I believe is easier for what you want, is special for OpenGL rendering and there is plenty information about it. Examples, lifecycle among others. Let me know if helped. If not, please, provide more info.
In my android application I have a ViewPager and 5 fragments. I previously used viewPager.setCurrentItem() to navigate, but the requirement for navigation animation has changed; For an example in some fragments when a previous fragment is called, we were asked not to show going back (left to right animation), instead show the user their moving to the next fragment (right to left animation). For an example in some cases user has to insert the same data again and again so instead of creating new fragmnets for these, we re-used the existing ones we created- so when the viewPager.setCurrentItem() is calling a fragment in the back (ex: we are now in 20th fragment and we are calling 10th fragment) it goes back and shows left to right animation.
Now we are not using the viewPager.setCurrentItem() method to navigate, instead we use FragmentTransaction. However we did not remove the fragments from the ViewPager anyway, expecting to complete this with minimum work (we are at the end of project when this requirement appeared)
But when we use the FragmentTransaction we have a new issue now. When we come back the onCreateView of fragmnets are getting called all the time! This didn't happen when we were using viewPager.setCurrentItem(). Lot of our code which should run only once are in this onCreateView.
Another issue is setUserVisibleHint() is called only in first fragment and that is also only at the initial run! All of our code which should run every time the fragmnet is displayed is located in this method.
Below is an example code, which demonstrate our issue.
MainActivity.java
public class MainActivity extends FragmentActivity {
private ViewPager viewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager=(ViewPager)findViewById(R.id.viewPager);
viewPager.setAdapter(new MyPagerAdapter2(getSupportFragmentManager()));
viewPager.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if (viewPager.getCurrentItem() == 0) {
return true;
}
if (viewPager.getCurrentItem() == 1) {
return true;
}
if (viewPager.getCurrentItem() == 2) {
return true;
}
if (viewPager.getCurrentItem() == 3) {
return true;
}
if (viewPager.getCurrentItem() == 4) {
return true;
}
return false;
}
});
}
private class MyPagerAdapter2 extends FragmentPagerAdapter {
public MyPagerAdapter2(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
switch(pos) {
case 0: return FirstFragment1.newInstance("FirstFragment_1");
case 1: return SecondFragment1.newInstance("SecondFragment_1");
case 2: return ThirdFragment1.newInstance("ThirdFragment_1");
case 3: return FourthFragment1.newInstance("FourthFragment_1");
case 4: return FifthFragment1.newInstance("FifthFragment_1");
default: return FirstFragment1.newInstance("DefaultFragment_1");
}
}
#Override
public int getCount() {
return 1;
}
}
public void setCurrentItem(int which) {
if(viewPager != null && which >= 0 && which <= 4) {
viewPager.setCurrentItem(which);
}
}
}
FirstFragment1.java
public class FirstFragment1 extends Fragment {
TextView textView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.first_frag_1, container, false);
TextView tv = (TextView) v.findViewById(R.id.tvFragFirst);
tv.setText("FRAGMENT 01");
textView=(TextView)v.findViewById(R.id.textView1);
textView.setText("Fragment Name : - 01");
Log.d("FRAGMENT_01", "ON_CREATE");
Button button1 = (Button) v.findViewById(R.id.nextButton);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (getActivity() != null) {
FragmentManager fragmentManager=getFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.setCustomAnimations(R.anim.from_right, R.anim.to_left);
transaction.replace(R.id.firstFragment, new SecondFragment1());
transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
transaction.addToBackStack(null);
transaction.commit();
}
}
});
return v;
}
public static FirstFragment1 newInstance(String text) {
FirstFragment1 f = new FirstFragment1();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
#Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
Activity a = getActivity();
if (a != null) a.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LOCKED);
// textView.setText("Fragment Name : - 01");
Log.d("FRAGMENT_01", "VISIBLE_HINT");
}
}
}
SecondFragment1.java
public class SecondFragment1 extends Fragment {
TextView textView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.second_frag_1, container, false);
TextView tv = (TextView) v.findViewById(R.id.tvFragSecond);
tv.setText("FRAGMENT 03");
textView=(TextView)v.findViewById(R.id.textView2);
textView.setText("Fragment Name : - 02");
Log.d("FRAGMENT_02", "ON_CREATE");
Button button=(Button)v.findViewById(R.id.printButton);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(getActivity() != null) {
FragmentManager fragmentManager=getFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.setCustomAnimations(R.anim.from_right, R.anim.to_left);
transaction.replace(R.id.secondFrag, new FirstFragment1());
transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
transaction.addToBackStack(null);
transaction.commit();
}
}
});
Button button1=(Button)v.findViewById(R.id.nextButton);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (getActivity() != null) {
FragmentManager fragmentManager=getFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.setCustomAnimations(R.anim.from_right, R.anim.to_left);
transaction.replace(R.id.secondFrag, new ThirdFragment1());
transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
transaction.addToBackStack(null);
transaction.commit();
}
}
});
return v;
}
public static SecondFragment1 newInstance(String text) {
SecondFragment1 f = new SecondFragment1();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
#Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if(isVisibleToUser) {
Activity a = getActivity();
if(a != null) a.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LOCKED);
Log.d("FRAGMENT_02","VISIBLE_HINT");
}
}
}
As you can see in our code, we use below to navigate between Fragments. (Below code shows navigating from first fragmnet to second)
FragmentManager fragmentManager=getFragmentManager();
FragmentTransaction transaction = fragmentManager.beginTransaction();
transaction.setCustomAnimations(R.anim.from_right, R.anim.to_left);
transaction.replace(R.id.firstFragment, new SecondFragment1());
transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
transaction.addToBackStack(null);
transaction.commit();
Looking at our code, and considering we have added the ViewPager as well, how can we make sure that onCreateView is only called once and setUserVisibleHint is called everytime the fragment is displayed?
there is challenges when using setUserVisibleHint is called.try viewPager.setOffscreenPageLimit(5); and use setMenuVisibility method and if you launch app on any fragment by notification
#Override
public void setMenuVisibility(boolean menuVisible) {
super.setMenuVisibility(menuVisible);
if(menuVisible && isResumed()){
// do your work here
}
if(!isResumed()){
// do your work when Activity is created
}
}
Put all of your code which you want should not be called everytime in onCreate() method and the code which you want should be called everytime in onCreateView() method.
I'm trying to implement the back press feature for a fragment and activity regarding the navigation drawer but it's not working. Does anyone know what I'm doing wrong / what is missing and what needs to be done in order to fix this?
activity class
public class BakerlooHDNActivity extends AppCompatActivity {
//save our header or result
private Drawer result = null;
// Declaring Views and Variables
ViewPager pager;
BakerlooHDNViewPagerAdapter adapter;
BakerlooHDNSlidingTabLayout bakerloohdntabs;
int Numboftabs = 2;
private int getFactorColor(int color, float factor) {
float[] hsv = new float[3];
Color.colorToHSV(color, hsv);
hsv[2] *= factor;
color = Color.HSVToColor(hsv);
return color;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bakerloo_hdn);
final String actionBarColor = "#B36305";
Toolbar mToolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(mToolbar);
if(getSupportActionBar()!=null) {
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(false);
getSupportActionBar().setTitle(Html.fromHtml("<font color='#FFFFFF'>" + getResources().getString(R.string.hdn) + "</font>"));
getSupportActionBar().setSubtitle(Html.fromHtml("<font color='#FFFFFF'>" + getResources().getString(R.string.zone_3) + "</font>"));
final Drawable upArrow = ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha);
upArrow.setColorFilter(getResources().getColor(R.color.white), PorterDuff.Mode.SRC_ATOP);
getSupportActionBar().setHomeAsUpIndicator(upArrow);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
getWindow().setStatusBarColor(getFactorColor(Color.parseColor(actionBarColor), 0.8f));
}
// start of navigation drawer
headerResult = new AccountHeaderBuilder()
.withActivity(getActivity())
.withCompactStyle(true)
.withHeaderBackground(R.color.bakerloo)
.withProfileImagesVisible(false)
.withTextColor(Color.parseColor("#FFFFFF"))
.withSelectionListEnabled(false)
.addProfiles(
new ProfileDrawerItem().withName(getString(R.string.hdn)).withEmail(getString(R.string.hello_world))
)
.build();
result = new DrawerBuilder()
.withActivity(getActivity())
.withAccountHeader(headerResult)
.withTranslucentStatusBar(false)
.withActionBarDrawerToggle(false)
.withSelectedItem(-1)
.addDrawerItems(
new PrimaryDrawerItem().withName(R.string.hello_world).withIdentifier(1).withCheckable(false)
)
.build();
// end of navigation drawer
}
#Override
public void onBackPressed() {
if (result.isDrawerOpen()) {
result.closeDrawer();
} else {
super.onBackPressed();
}
LocalBroadcastManager.getInstance(getApplicationContext()).sendBroadcast(new Intent("BACKPRESSED_TAG"));
}
}
fragment class
public class FragmentBakerlooHDN extends android.support.v4.app.Fragment {
public FragmentBakerlooHDN() {
// Required empty constructor
}
BroadcastReceiver onNotice = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// do stuff when back in activity is pressed
result.closeDrawer();
}
};
// Declaring navigation drawer
private AccountHeader headerResult = null;
private Drawer result = null;
/**
* Whether or not the activity is in two-pane mode, i.e. running on a tablet
* device.
*/
private boolean mTwoPane;
#Override
public void onCreate(Bundle savedInstanceState) {
LocalBroadcastManager.getInstance(getActivity()).registerReceiver(onNotice, new IntentFilter("BACKPRESSED_TAG"));
super.onCreate(savedInstanceState);
}
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_bakerloo_hdn, container, false);
// start of navigation drawer
headerResult = new AccountHeaderBuilder()
.withActivity(getActivity())
.withCompactStyle(true)
.withHeaderBackground(R.color.bakerloo)
.withProfileImagesVisible(false)
.withTextColor(Color.parseColor("#FFFFFF"))
.withSelectionListEnabled(false)
.addProfiles(
new ProfileDrawerItem().withName(getString(R.string.hdn)).withEmail(getString(R.string.hello_world))
)
.build();
result = new DrawerBuilder()
.withActivity(getActivity())
.withAccountHeader(headerResult)
.withTranslucentStatusBar(false)
.withActionBarDrawerToggle(false)
.withSelectedItem(-1)
.addDrawerItems(
new PrimaryDrawerItem().withName(R.string.hello_world).withIdentifier(1).withCheckable(false)
)
.build();
// end of navigation drawer
super.onCreate(savedInstanceState);
return v;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
View v = getView();
super.onActivityCreated(savedInstanceState);
}
}
try this:
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
#Override
public void onCreate() {
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerList = (ListView) findViewById(R.id.navdrawer);
}
#Override
public void onBackPressed() {
if(mDrawerLayout.isDrawerOpen(mDrawerList)) mDrawerLayout.closeDrawer(mDrawerList);
else super.onBackPressed();
}
EDIT:
You can use LocalBroadcastManager to update fragment when in activity back is pressed:
in fragment add new BroadcastReceiver() Instance:
BroadcastReceiver onNotice = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// do stuff when back in activity is pressed
// headerResult.closeDrawer();
}
};
and register it with tag in onCreate method:
LocalBroadcastManager.getInstance(this).registerReceiver(onNotice,
new IntentFilter("BACKPRESSED_TAG"));
Then, in Activity OnBackPressed method call broadcast:
LocalBroadcastManager.getInstance(context).sendBroadcast(new Intent("BACKPRESSED_TAG"));
Do you have a reference inside your code to the interface? Looks like you're calling that interface directly hence the errors. Try renaming that method too. It might be conflicting with the super class's onBackPressed method.
Your problem is that your interface is named exactly as the property you are trying to use.
Rename it and use a instance.
#Override
public void onBackPressed() {
OnBackPressedListener instance = getSettedListener();
if (result.isDrawerOpen()) {
result.closeDrawer();
} else {
return instance.onBackPressed();
}
}
public interface OnBackPressedListener {
boolean onBackPressed();
}
This code would compile if you also implement the method getSettedListener on your code (that could be like the following):
public OnBackPressedListener getSettedListener() {
return new OnBackPressedListener(){
boolean onBackPressed(){
if(shouldConsumeBack)
return consumeBack();
else return false;
};
}
}
But this code could return the Fragment that does implements the method.