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How to go to previous page in Webview present in a Fragment?

I have an actvity called SearchActivity. It has a searchbar and 4 tabs with Webviews. When I enter text and click on search, all the tabs are loading respective urls that I'm passing to them. But when I click on back button I want all the webviews to go back to the previous page, instead the activity closes. I've tried the below code, but it doesn't work. This the code of SearchActivity
public boolean onKeyDown(int keyCode, KeyEvent event) {
int count = getFragmentManager().getBackStackEntryCount();
if (count != 0 && (keyCode == KeyEvent.KEYCODE_BACK) && webView.canGoBack()) {
webView.goBack();
getFragmentManager().popBackStack();
//additional code
} else {
super.onBackPressed();
}
return super.onKeyDown(keyCode, event);
}

1.Add an interface on SearchActivity and implement that interface on MyFragment to communicate between SearchActivity and MyFragment.
2.Override onBackPressed() method of SearchActivity to add custom functions when the back button is pressed and check if fragment's WebView can go back via goBack listener. If can go back, then do so. If can not, call super.onBackPressed().
SearchActivity.java
public class SearchActivity extends AppCompatActivity{
public interface goBack{
boolean canGoBack();
}
#Override
public void onBackPressed() {
Fragment fragment = getSupportFragmentManager().findFragmentById(R.id.fragment_container);
//fragment_container is a layout where fragment is populated
if (fragment instanceof goBack && fragment.canGoBack()) {
return;
}
super.onBackPressed();
}
}
MyFragment.java
public class MyFragment extends Fragment implements SearchActivity.goBack{
#Override
public boolean canGoBack() {
if (webView.canGoBack()) {
webView.goBack();
return true;
}
return false;
}

I would use an interface:
Public Interface InterfaceBackPressed {
onInterfaceBackPressed();
}
Then in your Activity:
public class SearchActivity extends Activity {
...
#Override public void onBackPressed() {
Fragment fragment = getSupportFragmentManager().findFragmentById(R.id.container);
if (!(fragment instanceof InterfaceBackPressed) || !((InterfaceBackPressed) fragment).onBackPressed()) {
super.onInterfaceBackPressed();
}
}
}
and have every fragment implement your interface:
public class MyFragment extends Fragment implements IOnBackPressed{
#Override
public void onInterfaceBackPressed() {
if (webView.canGoBack()) {
webView.goBack();
} else {
super.onInterfaceBackPressed();
}
}
}

implementing onbackpressed in android

i have activity1 takes me to activity2 that takes me to fragment. i would like from fragment to go back to activity2
public void onBackPressed() {
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}

#Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
}
else
super.onBackPressed();
}

While adding fragment from activity2 add it to backstack like this
getSupportFragmentManager().beginTransaction()
.replace(R.id.frame_layout, new SampleFragment())
.addToBackStack(SampleFragment.class.getSimpleName())
.commit();
And onBackPressed check if the fragment is present in backstack and pop it
#Override
public void onBackPressed() {
if(getSupportFragmentManager().getBackStackEntryCount()>0){
Fragment fragment=getSupportFragmentManager().findFragmentById(R.id.YOUR_FRAME_LAYOUT_ID);
if(fragment!=null && fragment.getClass().getSimpleName().equalsIgnoreCase(SampleFragment.class.getSimpleName())){
getSupportFragmentManager().popBackStackImmediate();
}
}else {
super.onBackPressed();
}
}

on fragments get the backpressed event and there call the
getactivity().getsupportfragmentmanager().popbackstack();

Add that fragment transaction to backstack.

Onbackpressed redirect to particular fragment

In my app i have navigation drawer,So i have one MainActivity and rest are fragments. My app is working fine. Whenever i press back button it redirect to previous fragment.it works fine.but what i want is after successful payment i am displaying Successful payment page,on this page when user press back button i want to redirect to HomeFragment,but right now it goes to Placeorder fragment.
#Override
public void onBackPressed() {
if(getFragmentManager().getBackStackEntryCount() == 0) {
super.onBackPressed();
}
else {
getFragmentManager().popBackStack();
}
}

Override your onBackPress method:
#Override
public void onBackPressed() {
if (fragment != null && fragment.getChildFragmentManager().getBackStackEntryCount() > 0){
fragment.getChildFragmentManager().popBackStack();
}else {
super.onBackPressed();
}
}

One way would be saving previous fragment (previousFragment) variable while opening new fragment and making it null when you are in first or placeholder fragment .... then check value of previousFragment inside onBackPressed method , if null perform exit operation else replace fragment with previousFragment by which you will get back to previous fragment on back press.

You should simulate function as below in abstract class fragment
/**
* Handle "Back" key pressed.
* #return TRUE if the "Back" key pressed was handled. FALSE indicate it's not handled and parent class can handle it.
*/
public abstract boolean onBackPressed()
And in MainActivity, you will handle this function
#Override
public void onBackPressed() {
if (mSelectedFragment != null && mSelectedFragment.onBackPressed()) {
return;
} else {
super.onBackPressed
}
}

inside your onBackPressed() do like this:
#Override
public void onBackPressed() {
if(getSupportFragmentManger.findFragmentByTag("paymentFragment") != null){
//add homeFragment;
}
else{
if(getFragmentManager().getBackStackEntryCount() == 0) {
super.onBackPressed();
}
else {
getFragmentManager().popBackStack();
}
}
}

you can set some global variable (true when payment is success else false) in Application class and in onbackpressed of your activity just check that variable is true or not.Then in backpressed of your activity call this function.
public void clearBackStack() {
FragmentManager manager = getSupportFragmentManager();
if (manager.getBackStackEntryCount() > 0) {
FragmentManager.BackStackEntry first = manager.getBackStackEntryAt(0);
manager.popBackStack(first.getId(), FragmentManager.POP_BACK_STACK_INCLUSIVE);
}
}

Use:
fragmentTransaction.replace(R.id.fragment_container, mFeedFragment);
fragmentTransaction.commit();
Don't do this:
fragmentTransaction.addToBackStack(null);

Follow this simple method
declare an integer as
public int count;
initialise this count as count=0 in your main page
now include this in your main activity
#Override
public void onBackPressed() {
if (count == 1) {
if (exit) {
super.onBackPressed();
return;
} else {
Toast.makeText(this, "Press Back again to Exit.", Toast.LENGTH_SHORT).show();
exit = true;
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
exit = false;
}
}, 2000);
}
}else {
toolbar.setTitle("Home");
mDrawerLayout.closeDrawers();
count=1;
display(0);
}
}

android activity onBackPressed not called

#Override
public void onBackPressed() {
if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
FragmentManager.BackStackEntry bSE = getSupportFragmentManager().getBackStackEntryAt(getSupportFragmentManager().getBackStackEntryCount() - 1);
Fragment frag = getSupportFragmentManager().findFragmentByTag(bSE.getName());
if (frag instanceof BackButtonBlocker)
{
BackButtonBlocker callback = (BackButtonBlocker) frag;
callback.onBackPressed();
}
else {
getSupportFragmentManager().popBackStack();
}
} else {
super.onBackPressed();
}
}
BackButtonBlocker interface is for callback. my fragment implements BackButtonBlocker but sometimes onBackPressed not occurs (onKeyUp as well).
when I open navigation drawer, onBackPressed and full logic works exactly.
why should activity lose focus?
android.support.v4.app.Fragment
public interface BackButtonBlocker{ void onBackPressed();}

take out super.onBackPressed(); from else{}

What I have done is that, I have not implemented any interface to handle back pressed see below.
#Override
public void onBackPressed() {
if (getDrawerLayout().isDrawerOpen(GravityCompat.START)) {
closeLeftMenu();
}
else {
if (getSupportFragmentManager().getBackStackEntryCount() > 1) {
super.onBackPressed();
} else {
finish(); // Means it is home and you can exit it from here.
}
}}
When drawer is open just close it then use your code.

I fixed this issue by adding setFocusableInTouchMode(true); requestFocus(); on Mainactivity's container view

Popbackstack Finishes Activity in OnBackPressed

I have an Activity with two Fragments (List & Details), in onCreate(), I start the List Fragment if savedInstance is null like so
public static final int CLIENT_LIST_FRAGMENT = 1;
public static final int CLIENT_DETAILS_FRAGMENT = 2;
private int currentFragment = 0;
if (savedInstanceState == null) {
//On first run, start the list fragment
if (currentFragment == 0) {
ClientListFragment listFrag = new ClientListFragment();
getSupportFragmentManager().beginTransaction()
.add(R.id.container_client, listFrag, Constants.CLIENT_LIST_FRAGMENT_TAG)
.commit();
currentFragment = CLIENT_LIST_FRAGMENT;
} else {
switch (currentFragment) {
case CLIENT_LIST_FRAGMENT:
addListFragment();
break;
case CLIENT_DETAILS_FRAGMENT:
addDetailsFragment(0);
break;
}
}
}
And here is the method that add the DetailsFragment and ListFragment as needed
private void addListFragment(){
ClientDetailsFragment listFrag = new ClientDetailsFragment();
getSupportFragmentManager().beginTransaction()
.replace(R.id.container_client, listFrag, Constants.CLIENT_LIST_FRAGMENT_TAG)
.addToBackStack("details")
.commit();
currentFragment = CLIENT_LIST_FRAGMENT;
}
private void addDetailsFragment(long companyId){
ClientDetailsFragment detailsFrag = ClientDetailsFragment.newInstance(companyId);
getSupportFragmentManager().beginTransaction()
.replace(R.id.container_client, detailsFrag, Constants.CLIENT_DETAILS_TAG)
.addToBackStack(null)
.commit();
currentFragment = CLIENT_DETAILS_FRAGMENT;
}
This works as expected except that when I click the back button from the Details Fragment, instead of taking me back to the List Fragment, it actually finishes the Activity. It goes back to the List Fragment for a split second and then finishes the host Activity and goes back to the calling Activity. How can I stop this behavior, after going through a lot of onBackpress related question on SO here is my overide of the onBackPressed
#Override
public void onBackPressed() {
if (currentFragment == CLIENT_DETAILS_FRAGMENT){
getSupportFragmentManager().popBackStackImmediate();
}else {
super.onBackPressed();
}
}
Thanks

Activity onBackPressed() should be:
For android.support.v4.app.Fragment
#Override
public void onBackPressed() {
if (getSupportFragmentManager().getBackStackEntryCount() > 1)
getSupportFragmentManager().popBackStack();
else
finish();
}
For android.app.Fragment
#Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 1)
getFragmentManager().popBackStack();
else
finish();
}

I usually check whether the current fragment instance belongs to the fragment that invoked onBackPressed(). This code is untested; it's just to give you an idea on how to proceed. I hope you are not calling this.finish() on this Activity.
#Override
public void onBackPressed() {
Fragment fragment = getSuportFragmentManager().findFragmentByTag(Constants.CLIENT_DETAILS_TAG);
if (fragment instanceof ClientDetailsFragment) {
getSupportFragmentManager().popBackStackImmediate();
}
else {
super.onBackPressed();
}
}
Let me know if that helps.

Good Lord, I was chasing the wrong shadow for two days. I was listening, handling and overriding the wrong event.
This SO question saved me Why is onBackPressed() not being called?
And the gist is "onBackPressed() is invoked when user clicks on a hardware back button (or on the 'up' button in the navigation bar), not the button in the action bar. For this one you need to override onOptionsItemSelected() method. Example:"
I was catching this event the fragment and calling getActivity.onBackpressed. When I stopped this, it became obvious to me that the onBackPressed is not being called. Here is my solution, may not be optimal but it works
if (item.getItemId() == android.R.id.home){
if (currentFragment == CLIENT_DETAILS_FRAGMENT){
getSupportFragmentManager().popBackStackImmediate();
currentFragment = CLIENT_LIST_FRAGMENT;
return true;
}
}

if (currentFragment == 0) {
ClientListFragment listFrag = new ClientListFragment();
getSupportFragmentManager().beginTransaction()
.add(R.id.container_client, listFrag, Constants.CLIENT_LIST_FRAGMENT_TAG)
.commit();
currentFragment = CLIENT_LIST_FRAGMENT;
}
while changing this add to addToBackStack()
and,
change onBackPressed() like,
#Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() == 1) {
MainActivity.this.finish();
}
else {
getFragmentManager().popBackStack();
}
}
Hope, this will work.