My app flow is:
Activity A -> Activity B (this activity has buttons which on click open fragments)
I want that when I am on Activity B's fragments, on back pressed the flow should be to Activity B and when I am on Activity B then on back pressed app should exit.
I am currently using:
#Override
public void onBackPressed() {
if(getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStackImmediate();
}
else {
super.onBackPressed();
}
}
It's working fine when back pressed on Activity B's fragments, but it's going to Activity A when pressed back from Activity B(and that too for some reason nothing is being displayed in Activity A).
EDIT
My code for calling fragment:
faqsBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mLoginSubmit.setVisibility(View.GONE);
Bundle b1 = new Bundle();
b1.putString("ComingFrom","Login");
android.support.v4.app.Fragment faqsFragment = new fragment11Faqs();
faqsFragment.setArguments(b1);
android.support.v4.app.FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.framelayoutfaqs,faqsFragment);
transaction.addToBackStack(faqsFragment.toString());
transaction.commit();
}
});
You should call finish() when you call Activity B right after declaring its intent from ActivityA
Like this
Intent intent=new Intent(ActivityA.this,ActivityB.class);
startActivity(intent);
finish();
And you code for backstack is fine in activity b just add finish() after super.onBackPressed();
#Override
public void onBackPressed() {
if(getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStackImmediate();
}
else {
super.onBackPressed();
finish();
}
}
Here is how to add fragment to backstack
Fragment cameraEditing = new Editing(); FragmentManager
fragmentManager = getFragmentManager(); FragmentTransaction
fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.cameraLayout,
cameraEditing,"cameraEditing");
fragmentTransaction.addToBackStack("cameraEditing");
fragmentTransaction.commit();
Related
I want to when button clicked to return to previous fragment. This is how I create fragment:
getActivity().getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragment_container, statisticsSpecificStudentFragment)
.addToBackStack("StatisticsStudentOverallFragment")
.commit();
This is how I try and return to this fragment, from whom I started new fragment:
btDone.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
getActivity().getSupportFragmentManager().popBackStack();
}
});
All that happends is that it reloads current fragment, like I added current one to stack but I did not.
Try
popBackStack("StatisticsStudentOverallFragment")
Or
addToBackStack(null)
and keep popBackStack() like you have it already.
I want to handle onBackPressed in fragment
I use following code in my activity but this return 0
#Override
public void onBackPressed() {
int count = getFragmentManager().getBackStackEntryCount();
Toast.makeText(getBaseContext(), ""+count, Toast.LENGTH_SHORT).show();
if (count == 1) {
super.onBackPressed();
//additional code
} else {
getFragmentManager().popBackStack();
}
}
Just add .addToBackStack(null) in your Activity or Fragment . When you adding or replacing fragment. Like below
getSupportFragmentManager().beginTransaction().replace(R.id.parent_layout, new MyFragment()).addToBackStack(null).commit();
Note:- you don't have to do anything in your onBackPressed() method.
Just app this line when you want to replace any fragment and manage backsack on Fragment.
ClientHome per = new ClientHome();
Bundle bundle = new Bundle();
bundle.putString("usertype", "client");
per.setArguments(bundle);
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.setCustomAnimations(R.anim.slide_from_left, R.anim.slide_to_right);
fragmentTransaction.replace(R.id.content_frame, per, "tag");
fragmentTransaction.addToBackStack("tag");
fragmentTransaction.commit();
In my app, am using a navigation drawer (in Fragment A) to navigate to fragments:
public void displayView(int viewId){
Fragment fragment = null;
String title = getString(R.string.app_name);
switch (viewId) {
case R.id.nav_menu:
fragment = new MenuFragment();
title = getString(R.string.menu_title);
viewIsAtHome = false;
break;
case R.id.nav_reservation:
fragment = new ReservationFragment();
title = getString(R.string.reservation_title);
viewIsAtHome = false;
break;
...
if (fragment != null) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame, fragment);
ft.commit();
}
// set the toolbar title
if (getSupportActionBar() != null) {
getSupportActionBar().setTitle(title);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
}
}
displayView() is called in onNavigationItemSelected:
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
displayView(item.getItemId());
return true;
}
Now, in ReservationFragment I am displaying a list of reservations and a FloatingActionButton to start Activity B where the user can add a reservation if there are no reservations. When the user is done adding a reservation, I want to display it in the Reservation fragment. This requires me to "go back" to the Fragment.How do I accomplish this since Activity B knows nothing about Activity A?
What I've tried:
I tried creating a method in Activity A like this:
public void navigateToFragment(int viewId) {
displayView(R.id.nav_reservation);
}
and then called this method from Activity B:
saveButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
new MainActivity().navigateToFragment(R.id.nav_reservation);
//MainActivity is Activity A
}
});
the app crashes due to a nullPointerException in displayView() from the line:
String title = getString(R.string.app_name);
This isn't surprising since am creating a new MainActivity object that knows nothing about the previous state of the Activity, right?
This question mirrors my problem but is based on Settings so I can't really use the answer in my case.
How do I accomplish this task?
There are three quick methods that come to my mind. First you can start activityB with startActivityForResult and handle the result in activityA after user does what he wants in activityB. Second you can set activityA as singleTop and before finishing activityB you can startActivityA with clearTop an intent flag called clear_top(https://developer.android.com/reference/android/content/Intent.html#FLAG_ACTIVITY_CLEAR_TOP).
Last but not the least, you can connect two activity by binding service in both activities and communicate via that service that you bound.
I'm attempting to implement a back stack while using fragments, but when using the Back button, I keep getting taken out of the app to the home screen.
Activity opens fragment A; Fragment A has a clickable TextView that opens fragment B (this works). Hitting BACK should return me to fragment A, but it takes me to the home screen instead.
Here is the activity's call to the opening of fragment A in onCreate:
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add(R.id.fragment_layout_container, new FragmentLogin(), "fragment_login")
.addToBackStack("login_screen")
.commit();
Log.d("Back", getFragmentManager().getBackStackEntryCount() +" <- Entry Count at LoginActivity.onCreate" );
At this point, the Log prints 0 <- Entry Count at LoginActivity.onCreate. Something I've done wrong keeps this from printing 1.
Then, the Fragment A has this listener:
forgottenPassword.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();
fragmentTransaction.replace(R.id.fragment_layout_container, new FragmentForgottenPassword(), "fragment_password")
.addToBackStack("forgotten_password")
.commit();
Log.d("Back", getFragmentManager().getBackStackEntryCount() + " <- Entry Count at FragmentLogin.onCreateView.Listener");
}
});
The Log here prints 1 <- Entry Count at FragmentLogin.onCreateView.Listener. Here, the listener works and opens fragment B - but the back button returns me to the home screen.
Use this in your Activity it should pop out the fragments already added to backstack
#Override
public void onBackPressed()
{
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
Try Like This,
public void replaceFragment(Fragment fragment, boolean addToBackStack) {
FragmentTransaction transaction = getFragmentManager()
.beginTransaction();
if (addToBackStack) {
transaction.addToBackStack(null);
} else {
getFragmentManager().popBackStack(null,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
transaction.replace(R.id.fragment_layout_container, fragment);
transaction.commitAllowingStateLoss();
getFragmentManager().executePendingTransactions();
}
and Used it like this,
replaceFragment(new FragmentForgottenPassword(), true);
There is a GitHub library that will do this work for you!https://github.com/rathodchintan/Fragment-Back-StackWhenever you are displaying any new fragment, just push that fragment into stack using following code.
//here this fragment is our first fragment
homeListFragment = new HomeListFragment();
fragmentStack.push(homeListFragment);It has many other stack options too.
Solve by using getActivity()
I have this MainActivity.java and RepeatEntry.java
inside my MainActivity i have this code to have RepeatEntry ui
//i did hide two linear layout here with buttons and edittext inside it ,using the following method
hideTwoLinearLayout();
showCategoryContainerLayout();
Fragment fragment = new RepeatEntry();
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
//category_cont is a linear layout container for my fragment
ft.replace(R.id.category_cont, fragment);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.commit();
inside my RepeatEntry.java sample code
Button k = (Button) v.findViewById(R.id.button);
k.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Intent intent = new Intent(getActivity(),MainActivity.class);
// startActivity(intent);
// if i use popBackStack and also remove the code for intent , i cannot show what i hide
//note i have a method inside mainactivity to showTwoLinearLayout()
getFragmentManager().popBackStack();
}
});
Now my question is, do i have other option other than using intent to go back to MainActivity view
Note:Edited
You can add the transaction to backstack and then reverse with poping the backstack the code is here
Fragment fragment = new RepeatEntry();
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
//category_cont is a linear layout container for my fragment
ft.replace(R.id.category_cont, fragment).addToBackStack("tag");
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.commit();
And for going back to the activity view call this to pop backstack
FragmentManager fm = getFragmentManager();
fm.popBackStack();
Also you can use the tag to poping back the specific transaction with
fm.popBackStack("tag");
There is a method called onAttach in your fragment. You can write an interface and assign your fragment's activity like:
private MyFragmentListener mListener;
#Override public void onAttach(Activity activity) {
super.onAttach(activity);
mListener = ((MainActivity) activity);
}
public interface MyFragmentListener{
void onClicked(int value);
}
//Call your listener when button clicked or other events
... mListener.onClicked(position);
Or another solution is to use Otto or Eventbus to get rid unnecessary code
You can also go back in Fragment like
getActivity().getSupportFragmentManager().popBackStack();
any way i solve my problem just in case if anyone might see this.I came up with two solution which i think the first one is best for me.Thanks to Adnan Basar who give me idea.
First solution is so simple by just adding this code inside my onClick event
((MainActivity) getActivity()).showTwoLinearLayout();
((MainActivity) getActivity()).hideCategoryContainerLayout();
Second Solution I created Activity after extends Fragment{
Activity mainActivity;
And use override methods
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
mainActivity= activity;
}
#Override
public void onDestroy() {
super.onDestroy();
// this is where i call the method for showing the twolinearlayout again
((MainActivity) mainActivity).showTwoLinearLayout();
((MainActivity) mainActivity).hideCategoryContainerLayout();
}