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Back button in toolbar not working in android fragment [duplicate]

This question already has answers here:
Manage toolbar's navigation and back button from fragment in android
(11 answers)
Closed 5 years ago.
I am enabled back button in android fragment using below code.But when I click on it triggers side navigation menu.
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public void onResume() {
super.onResume();
((AppCompatActivity) getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);
((AppCompatActivity) getActivity()).getSupportActionBar().setHomeButtonEnabled(true);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
getActivity().onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

Try this:
Use this code inside class where you are initialising toolbar and drawer layout.
getSupportFragmentManager().addOnBackStackChangedListener(new FragmentManager.OnBackStackChangedListener() {
#Override
public void onBackStackChanged() {
if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
drawerFragment.mDrawerToggle.setDrawerIndicatorEnabled(false);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);// show back button
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
} else {
//show hamburger
drawerFragment.mDrawerToggle.setDrawerIndicatorEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
drawerFragment.mDrawerToggle.syncState();
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
drawerFragment.mDrawerLayout.openDrawer(GravityCompat.START);
}
});
}
}
});
Replace your fragment like below:
Fragment fragment = getHomeFragment();
FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
fragmentTransaction.setCustomAnimations(android.R.anim.fade_in,
android.R.anim.fade_out);
fragmentTransaction.replace(R.id.frame, fragment, CURRENT_TAG);
if (fragment != new HomeFragment()){
fragmentTransaction.addToBackStack(null); //This line is important
}
fragmentTransaction.commit();

Go back to fragment from activity

I have the following Activity code:-
public class legislator_info extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_legislator_info);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
toolbar.setTitle("Legislator Info");
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
Intent i = getIntent();
String bioguide = i.getExtras().getString("Person");
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// click on 'up' button in the action bar, handle it here
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
So basically I have a fragment which has a list view displayed in it. On click of a list Item I start this activity and I want to go back to the previous fragment on the back button click. I tried the above code but I am not able to travel back. Am pretty new at this any help is appreciated.
I have added my fragment in the following way:-
android.support.v4.app.FragmentManager fm = getSupportFragmentManager();
android.support.v4.app.FragmentTransaction ft = fm.beginTransaction();
LegislatorFragment lf = new LegislatorFragment();
ft.replace(R.id.fragment_container,lf);
ft.addToBackStack(null);
ft.commit();

I am still not clear what you want to achieve but you can try this
#Override
public void onBackPressed() {
super.onBackPressed();
finish();
}
EDIT:
case android.R.id.home:
//call onBackPressed here
onBackPressed();
return true;

You have to override onOptionsItemSelected because you are trying with Action bar's back button.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
Then override BackPressed -
#Override
public void onBackPressed()
{
FragmentManager fm = getSupportFragmentManager();
if (fm.getBackStackEntryCount() > 0) {
fm.popBackStack();
}
else {
super.onBackPressed();
}
}

Why not works ClickListeners for Toolbar?

I use MaterialDrawer and code MainActivity is:
public class MainActivity extends AppCompatActivity implements KitchenFragment.CallbackOne {
public static final String TAG = "myLogTag";
private Toolbar mToolbar;
private Drawer drawer;
private FragmentManager fm;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mToolbar = (Toolbar) findViewById(R.id.toolbar);
mToolbar.setNavigationOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.d(TAG, "CLICK NOCL");
}
});
setSupportActionBar(mToolbar);
// getSupportActionBar().setDisplayHomeAsUpEnabled(false);
fm = getFragmentManager();
Fragment fragment = fm.findFragmentById(R.id.content_frame);
if (fragment == null) {
fragment = MenuFragment.newInstance();
fm.beginTransaction()
.add(R.id.content_frame, fragment)
.commit();
}
drawer = new DrawerBuilder()
.withActivity(this)
.withToolbar(mToolbar)
.withActionBarDrawerToggle(true)
.withHeader(R.layout.drawer_header)
.addDrawerItems(
new PrimaryDrawerItem().withName(R.string.menu).withIdentifier(1),
new PrimaryDrawerItem().withName(R.string.kitchen_title).withIdentifier(2),
new PrimaryDrawerItem().withName(R.string.information_title).withEnabled(false)
).withOnDrawerItemClickListener(new Drawer.OnDrawerItemClickListener() {
#Override
public boolean onItemClick(View view, int position, IDrawerItem drawerItem) {
Log.d(TAG, "position clicked: " + position);
Fragment fragment = MenuFragment.newInstance();
switch (position) {
case 1:
fragment = MenuFragment.newInstance();
break;
case 2:
fragment = KitchenFragment.newInstance();
break;
default:
fragment = new Fragment();
}
fm.beginTransaction().replace(R.id.content_frame, fragment).commit();
return false;
}
})
.withFireOnInitialOnClick(true)
.withSavedInstance(savedInstanceState)
.withOnDrawerNavigationListener(new Drawer.OnDrawerNavigationListener() {
#Override
public boolean onNavigationClickListener(View view) {
Log.d(TAG, "CLICK in DNL");
if (!drawer.getActionBarDrawerToggle().isDrawerIndicatorEnabled()) {
onBackPressed();
return true;
} else
return false;
}
})
.build();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
Log.d(TAG, "CLICK OIS");
switch (item.getItemId()) {
case R.id.action_settings:
return true;
case android.R.id.home:
getFragmentManager().popBackStackImmediate();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
protected void onSaveInstanceState(Bundle outState) {
outState = drawer.saveInstanceState(outState);
super.onSaveInstanceState(outState);
}
#Override
public void onBackPressed() {
if (drawer.isDrawerOpen())
drawer.closeDrawer();
else if (getFragmentManager().getBackStackEntryCount() == 1) {
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
drawer.getActionBarDrawerToggle().syncState();
getFragmentManager().popBackStack();
} else if (getFragmentManager().getBackStackEntryCount() > 0)
getFragmentManager().popBackStack();
else
super.onBackPressed();
}
#Override
public void setFirstSelected() {
drawer.setSelection(1);
}
}
I'm trying to trace a Click in mToolbar.setNavigationOnClickListener
and withOnDrawerNavigationListener and onOptionsItemSelected.
None of the listeners not reacted for clicking.
How you see i use Activity that launches Fragment (1), which in turn lets Fragment (2 and 3). In 2 and 3 Fragment in OnCreate i use ((AppCompatActivity)getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true); , and I need to by pressing the back button (in toolbar), returning the previous fragment, and not open Drawer

The MaterialDrawer already handles all the listeners for you. If you need to do an action after the drawer opens or closes you can provide the listener via the DrawerBuilder
For the icon you have this listener:
OnDrawerNavigationListener
https://github.com/mikepenz/MaterialDrawer/blob/develop/library/src/main/java/com/mikepenz/materialdrawer/DrawerBuilder.java#L1158
For drawer close / open this listener:
OnDrawerListener
https://github.com/mikepenz/MaterialDrawer/blob/develop/library/src/main/java/com/mikepenz/materialdrawer/DrawerBuilder.java#L1116

I suggest you to create new Activity using android studio wizard. File->New->Activity->Navigation Drawer Activity.
In that case ActionBarDrawerToaggle is used
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
This toggle contains click listener which handle open/close drawer functionality for you.
Also you can that item clicks implemented through OnNavigationItemSelectedListener.onNavigationItemSelected(MenuItem item)

MainActivity to fragment and back to MainActivity on pressing back button

I have a Mainactivity which contains a Layout which is parent of 4 sub layout. on clicking on sub layout i am going to a new fragment replacing main layout. But i cant go back to MainActivity after pressing Back button
MainActivity.java
public class MainActivity extends AppCompatActivity {
RelativeLayout aboutUs;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
aboutUs = (RelativeLayout) findViewById(R.id.aboutUs);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
//click methods goes here
public void clickAboutUs(View view){
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
FragmentAboutUs fragmentAboutUs = new FragmentAboutUs();
fragmentTransaction.replace(R.id.fragment_container,fragmentAboutUs);
fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
FragmentAboutUs.java
public class FragmentAboutUs extends Fragment
{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.about_us, container,false);
return view;
}
}
How to go back to main page again after pressing back button from fragment.

Try Like this
public boolean popFragment() {
boolean isPop = false;
Fragment currentFragment = getSupportFragmentManager()
.findFragmentById(R.id.flContent);
if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
isPop = true;
getSupportFragmentManager().popBackStackImmediate();
}
return isPop;
}
#Override
public void onBackPressed() {
if (!popFragment()) {
finish();
}
}
public void replaceFragment(Fragment fragment, boolean addToBackStack) {
FragmentTransaction transaction = getSupportFragmentManager()
.beginTransaction();
if (addToBackStack) {
transaction.addToBackStack(null);
} else {
getSupportFragmentManager().popBackStack(null,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
transaction.replace(R.id.fragment_container, fragment);
transaction.commit();
getSupportFragmentManager().executePendingTransactions();
}
add above method is in your parent Activity
And Use like
FragmentAboutUs fragmentAboutUs = new FragmentAboutUs();
replaceFragment(fragmentAboutUs , true);

If you have one Activity and four fragments then set onBackPressed() as below in your MainActivity.
#Override
public void onBackPressed()
{
super.onBackPressed();
finish();
}
And in fragments:
#Override
public void onResume() {
super.onResume();
new PlayListFragment();
getView().setFocusableInTouchMode(true);
getView().requestFocus();
getView().setOnKeyListener(new View.OnKeyListener() {
#Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
if (event.getAction() == KeyEvent.ACTION_UP && keyCode == KeyEvent.KEYCODE_BACK){
if(getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
}
return true;
}
return false;
}
});
}

You can Override the onBackPressed of MainActivity
#Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 1) {
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}

Here is how it can be done in Xamarin:
Load fragment (I wrote helper method for that, but it's not necessary):
public void LoadFragment(Activity activity, Fragment fragment)
{
var backStateName = fragment.GetType().Name;
var fm = activity.FragmentManager;
var ft = fm.BeginTransaction();
ft.Replace(Resource.Id.mainContainer, fragment);
ft.AddToBackStack(backStateName);
ft.Commit();
}
Back button (in MainActivity):
public override void OnBackPressed()
{
if (isNavDrawerOpen()) drawerLayout.CloseDrawers();
else
{
var backStackEntryCount = FragmentManager.BackStackEntryCount;
if (backStackEntryCount == 1) Finish();
else if (backStackEntryCount > 1) FragmentManager.PopBackStack();
else base.OnBackPressed();
}
}
isNavDrawerOpen method:
bool isNavDrawerOpen()
{
return drawerLayout != null && drawerLayout.IsDrawerOpen(Android.Support.V4.View.GravityCompat.Start);
}

actionbar up navigation with fragments

I have a tabbed Actionbar/viewpager layout with three tabs say A, B, and C. In tab C tab(fragment),I am adding another fragment say fragment D. with
DFragment f= new DFragment();
ft.add(android.R.id.content, f, "");
ft.remove(CFragment.this);
ft.addToBackStack(null);
ft.commit();
I modify actionbar in DFragment's onResume to add up button:
ActionBar ab = getActivity().getActionBar();
ab.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
ab.setDisplayHomeAsUpEnabled(true);
ab.setDisplayShowHomeEnabled(true);
Now in DFragment, when I press hardware(phone) Back button, I return to the original Tabbed(ABC) layout with CFragment selected. How can I achieve this functionality with actionbar up button?

Implement OnBackStackChangedListener and add this code to your Fragment Activity.
#Override
public void onCreate(Bundle savedInstanceState) {
//Listen for changes in the back stack
getSupportFragmentManager().addOnBackStackChangedListener(this);
//Handle when activity is recreated like on orientation Change
shouldDisplayHomeUp();
}
#Override
public void onBackStackChanged() {
shouldDisplayHomeUp();
}
public void shouldDisplayHomeUp(){
//Enable Up button only if there are entries in the back stack
boolean canGoBack = getSupportFragmentManager().getBackStackEntryCount()>0;
getSupportActionBar().setDisplayHomeAsUpEnabled(canGoBack);
}
#Override
public boolean onSupportNavigateUp() {
//This method is called when the up button is pressed. Just the pop back stack.
getSupportFragmentManager().popBackStack();
return true;
}

I got it. just override onOptionsItemSelected in hosting activity and popup the backstack, e.g.
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home: {
FragmentManager fm = getSupportFragmentManager();
if (fm.getBackStackEntryCount() > 0) {
fm.popBackStack();
return true;
}
break;
}
}
return super.onOptionsItemSelected(item);
}
Call getActionBar().setDisplayHomeAsUpEnabled(boolean); and getActionBar().setHomeButtonEnabled(boolean); in onBackStackChanged() as explained in an answer below.

If you have one parent activity and want this up button to work as a back button, you can use this code:
add this to the onCreate in your main activity class
getSupportFragmentManager().addOnBackStackChangedListener(new FragmentManager.OnBackStackChangedListener() {
#Override
public void onBackStackChanged() {
int stackHeight = getSupportFragmentManager().getBackStackEntryCount();
if (stackHeight > 0) { // if we have something on the stack (doesn't include the current shown fragment)
getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
} else {
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
getSupportActionBar().setHomeButtonEnabled(false);
}
}
});
and then add onOptionsItemSelected like so:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
getSupportFragmentManager().popBackStack();
return true;
....
}
I generally use this all the time and seems pretty legit

you can go back with up button like back button ;
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
super.onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}

I used a combination of Roger Garzon Nieto's and sohailaziz's answers. My app has a single MainActivity, and fragments A, B, C that are loaded into it. My "home" fragment (A) implements OnBackStackChangedListener, and checks the size of the backStack; if it's less than one, then it hides the UP button. Fragments B and C always load the back button (in my design, B is launched from A, and C is launched from B). The MainActivity itself just pops the backstack on UP button tap, and has methods to show/hide the button, which the fragments call:
MainActivity:
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
getSupportFragmentManager().popBackStack();
return true;
}
return super.onOptionsItemSelected(item);
}
public void showUpButton() { getSupportActionBar().setDisplayHomeAsUpEnabled(true); }
public void hideUpButton() { getSupportActionBar().setDisplayHomeAsUpEnabled(false); }
fragmentA (implements FragmentManager.OnBackStackChangedListener):
public void onCreate(Bundle savedinstanceSate) {
// listen to backstack changes
getActivity().getSupportFragmentManager().addOnBackStackChangedListener(this);
// other fragment init stuff
...
}
public void onBackStackChanged() {
// enable Up button only if there are entries on the backstack
if(getActivity().getSupportFragmentManager().getBackStackEntryCount() < 1) {
((MainActivity)getActivity()).hideUpButton();
}
}
fragmentB, fragmentC:
public void onCreate(Bundle savedinstanceSate) {
// show the UP button
((MainActivity)getActivity()).showUpButton();
// other fragment init stuff
...
}

I know this question is old, but may be someone (like me) also needs it.
If your Activity extends AppCompatActivity, you can use a simpler (two-step) solution:
1 - Whenever you add a non-home fragment just show the up button, right after commiting the fragment transaction. Like this:
// ... add a fragment
// Commit the transaction
transaction.commit();
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
2 - Then when UP button is pressed, you hide it.
#Override
public boolean onSupportNavigateUp() {
getSupportActionBar().setDisplayHomeAsUpEnabled(false);
return true;
}
That's it.

This worked for me. Override onSupportNavigateUp and onBackPressed, for example (code in Kotlin);
override fun onBackPressed() {
val count = supportFragmentManager.backStackEntryCount
if (count == 0) {
super.onBackPressed()
} else {
supportFragmentManager.popBackStack()
}
}
override fun onSupportNavigateUp(): Boolean {
super.onSupportNavigateUp()
onBackPressed()
return true
}
Now in the fragment, if you display the up arrow
activity.supportActionBar?.setDisplayHomeAsUpEnabled(true)
Clicking on it takes you back the previous activity.

Kotlin:
class MyActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
...
supportFragmentManager.addOnBackStackChangedListener { setupHomeAsUp() }
setupHomeAsUp()
}
private fun setupHomeAsUp() {
val shouldShow = 0 < supportFragmentManager.backStackEntryCount
supportActionBar?.setDisplayHomeAsUpEnabled(shouldShow)
}
override fun onSupportNavigateUp(): Boolean =
supportFragmentManager.popBackStack().run { true }
...
}

This is a very good and reliable solution: http://vinsol.com/blog/2014/10/01/handling-back-button-press-inside-fragments/
The guy has made an abstract fragment that handles the backPress behaviour and is switching between the active fragments using the strategy pattern.
For some of you there maybe a little drawback in the abstract class...
Shortly, the solution from the link goes like this:
// Abstract Fragment handling the back presses
public abstract class BackHandledFragment extends Fragment {
protected BackHandlerInterface backHandlerInterface;
public abstract String getTagText();
public abstract boolean onBackPressed();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(!(getActivity() instanceof BackHandlerInterface)) {
throw new ClassCastException("Hosting activity must implement BackHandlerInterface");
} else {
backHandlerInterface = (BackHandlerInterface) getActivity();
}
}
#Override
public void onStart() {
super.onStart();
// Mark this fragment as the selected Fragment.
backHandlerInterface.setSelectedFragment(this);
}
public interface BackHandlerInterface {
public void setSelectedFragment(BackHandledFragment backHandledFragment);
}
}
And usage in the activity:
// BASIC ACTIVITY CODE THAT LETS ITS FRAGMENT UTILIZE onBackPress EVENTS
// IN AN ADAPTIVE AND ORGANIZED PATTERN USING BackHandledFragment
public class TheActivity extends FragmentActivity implements BackHandlerInterface {
private BackHandledFragment selectedFragment;
#Override
public void onBackPressed() {
if(selectedFragment == null || !selectedFragment.onBackPressed()) {
// Selected fragment did not consume the back press event.
super.onBackPressed();
}
}
#Override
public void setSelectedFragment(BackHandledFragment selectedFragment) {
this.selectedFragment = selectedFragment;
}
}

If you want to go back to your previous activity if this activity has an empty stack of fragments:
This could be useful if you have a MainActivity and you are navigating to e.g. a SettingsActivity with nested prefernceScreens. NavigateUp will pop fragments until you can finish the SettingsActivity to go back to parentActivity/root.
/**
* On actionbar up-button popping fragments from stack until it is empty.
* #return true if fragment popped or returned to parent activity successfully.
*/
#Override
public boolean onSupportNavigateUp() {
//Pop back stack if the up button is pressed.
boolean canGoBack = getSupportFragmentManager().getBackStackEntryCount()>0;
if (canGoBack) {
getSupportFragmentManager().popBackStack();
} else {
finish();
return super.onSupportNavigateUp();
}
return true;
}
Note: setDisplayHomeAsUpEnabled(true); in fragment activities onCreate()