I want to remove a fragment and show a toast when I click a textView. My code shows the toast, but doesn't remove the fragment.
My method:
public void hide(View view) {
My_frag myFrag= new My_frag();
FragmentTransaction transaction = getSupportFragmentManager()
.beginTransaction();
transaction.remove(myFrag);
transaction.commit();
Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_LONG)
.show();
}
My_frag class:
public class My_frag extends android.support.v4.app.Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.my_frag_layout, container, false);
}
}
At some point you must create and add the Fragment correct? You are re-creating the fragment in your hide(...) method so you are trying to remove something that has never been added. Sure you may have added an instance, but not the instance you are trying to remove.
Instead, create a global variable Fragment fragToRemove in your Activity. When you create the fragment (that is where ever you do transaction.add(fragToRemove = new My_Frag);) you will hold an instance. then change your transaction.remove(myFrag) to transaction.remove(fragToRemove) and it should work just fine.
Take the instance of Fragment Transaction other than that was taken while adding fragment to activity and call remove method on that and pass the same instance of Fragment which was used at the time.
Example:
public class MainActivity extends AppCompatActivity {
FragmentTransaction fragmentTransaction;
BlankFragment blankFragment;
Button b;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b = (Button) findViewById(R.id.activity_button);
fragmentTransaction = getSupportFragmentManager().beginTransaction();
blankFragment=new BlankFragment(); //Fragment instance
fragmentTransaction.add(R.id.main_layout,blankFragment).commit();
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.remove(blankFragment).commit(); //created different
}
});
}
In the same way you can do in fragments also and can also remove fragment X on the click of component of fragment X.
Related
The signup page of my app is divided into three fragments. FragmentA, FragmentB and FragmentC which is attached to same activity. On clicking the next button which is present in FragmentA it will call FragmentB and same is for FragmentB and FragmentC. As I move forward the buttons of the previous fragment overlaps the current one. Below is my code. How can I avoid this situation?
MainActivity.class
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.signup_page);
init();
}
private void init() {
ViewPager2 viewPager = findViewById(R.id.signup_pager);
List<Fragment> fragmentList = new ArrayList<Fragment>();
FragmentA aFragment = new FragmentA();
FragmentB bFragment = new FragmentB();
fragmentList.add(aFragment);
fragmentList.add(bFragment);
SignupFragmentPagerAdapter signupFragmentPagerAdapter = new SignupFragmentPagerAdapter(this,fragmentList);
viewPager.setUserInputEnabled(false);
viewPager.setAdapter(signupFragmentPagerAdapter);
}
}
FragmentA.class
public class FragmentA extends Fragment {
EditText et_name;
Spinner sp_user_type;
Button bt_next;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fraga,container,false);
et_name = view.findViewById(R.id.editTextTextPersonName);
sp_user_type = view.findViewById(R.id.user_spinner);
bt_next = view.findViewById(R.id.button8);
bt_next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
FragmentB bFragment = new FragmentB();
FragmentManager manager = getParentFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.frag_a, bFragment);
transaction.addToBackStack(null);
transaction.commit();
}
});
return view;
}
}
FragmentB.class
public class FragmentB extends Fragment {
Button bt_next;
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragb,container,false);
bt_next = view.findViewById(R.id.button9);
bt_next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
FragmentC cFragment = new FragmentC();
FragmentManager manager = getParentFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.frag_b, Fragment);
transaction.addToBackStack(null);
transaction.commit();
}
});
return view;
}
}
Cause of your problem:
You are making fragment transaction (from A to B) within Fragment A itself; and not through the placeholder of these fragments (which is in your case the ViewPager itself; So the MainActivity still sees that the ViewPager is at the first page and therefore shows Fragment A in the background.
You have two options to solve this:
First: Since you're disable page scrolling; I don't see any use to
the ViewPager .. so you can just have a fragment placeholder in the
main activity, and make fragment transaction on this placeholder.
Second: if you have a need to the ViewPager, instead of making
fragment transaction, you can use
viewPager.setCurrentItem(position) and set the position to the
target fragment according to the order you add them in the adapter.
You can do that from your fragment when you hit the button using:
((MainActivity)requireActivity()).myViewPager.setCurrentItem(position)
How to access button id in an activity.
Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_meter);
if (Build.VERSION.SDK_INT >= 23) {
checkLocationPermission();
}
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
Fragment map = new Map();
fragmentTransaction.add(R.id.fragment_container, map);
fragmentTransaction.commit();
...
}
Fragment
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (view == null) {
view = inflater.inflate(R.layout.fragment_map, container, false);
Button button = (Button)getActivity().findViewById(R.id.btnStop);
}
How to implement setOnClickListener method of btnStop in my code fragment?
add this to fragment:
final View.OnClickListener btnClick = new View.OnClickListener() {
public void onClick(View v){
//button clicked
}
}
add this to activity onCreate:
Button button = (Button)getActivity().findViewById(R.id.btnStop);
button.setOnClickListener(map.btnClick );
another way:
add this to fragment:
Button btnStop;
add this to onCreate of Activity:
map.btnStop = (Button)getActivity().findViewById(R.id.btnStop);
Then in any event listener of fragment that is called after onCreate of Activity (for example onActivityCreated and onStart) you have access to the btnStop and you can set onClick listener for it.
You can create a method in the activity, probably like
public void yourMethod() {
button.performClick();// you can access all the components present in your activity
}
Now create an instance of the activity in the fragment and access this method.
YourActivity activityInstance = (YourActivity) getActivity();
And then you can access the method using the isntance of the activity like
activityInstance.yourMethod();
Whenever you want to perform a click function, you just have to call the funciton.
I have "home_fragment.java" class file in my project
which i need to be launched when the app starts.
but i am only able to add 'activities' as launch default,not fragments.
please help me to add a 'fragment' as a launch activity.
i am new to android ,thank you.
this is my home_fragment.java
public class home_fragment extends Fragment {
View myView;
Button more;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
View myview = inflater.inflate(R.layout.home_layout,container, false);
Button button = (Button) myview.findViewById(R.id.button5);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// do something
}
});
return myview;
}
}
you have to add the fragment into the activity and launch this activity.
it is not possible for fragment to be launched independently.
in empty activity add this xml
<fragment android:name="com.company.appName.fragments.FirstFragment"
android:id="#+id/fragment_place"
android:layout_width="match_parent"
android:layout_height="match_parent" />
and in activity onCreate method do this
Fragment fr = new FirstFragment();
fr.setArguments(args);
FragmentManager fm = getFragmentManager();
FragmentTransaction fragmentTransaction = fm.beginTransaction();
fragmentTransaction.replace(R.id.fragment_place, fr);
fragmentTransaction.commit();
hope this will help you.
Fragment must be launched from Activity.
You can do it by launching your fragment from your activity onCreate() method like this:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getFragmentManager().beginTransaction().replace(android.R.id.content, new MyFragment()).commit();
}
I'm trying to add a view in fragment B from fragment A, they both belong to the same activity but they are never running simultaneously
My activity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fm = getSupportFragmentManager();
Fragment_Main main = new Fragment_Main();
fm.beginTransaction()
.replace(R.id.mainContainer, main)
.commit();
/* Fragment_Main is a fragment with two buttons
* to either call fragment A or fragment B and
* mainContainer is a FrameLayout occupying the whole screen
*/
}
Fragment A:
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_subjects, container, false);
ButterKnife.bind(this, view);
AddButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentB.addMyView();
}
});
return view;
}
Fragment B:
public static void addMyView(){
final RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
params.setMargins(0, 200, 0, 0);
CustomView mView = new CustomView(mContext, "english", "a1", "10:12", "14:32");
mLayout.addView(mView, params);
// CustomView is the custom view I want to add
}
Question:
I know that a fragment can't communicate with another fragment directly, how do I tell the activity to add a view permanently to FragmentB when the method addMyView() is called?
Persisting for one activity lifecycle
FragmentA should set a flag (e.g. a boolean attribute) on the Activity instance.
When FragmentB is instantiated, the Activity should pass this flag to the created instance (e.g. via Bundle). FragmentB should then decide whether or not to add the View.
Persisting permanently
FragmentA should set a SharedPreferences flag.
FragmentB should check this flag in onCreateView and potentially add the View depending on the value.
General advice:
Solving communication between instances with static values/methods is almost always bad practice.
I have two fragment, "A" and "B".
When I return (BackPressed) to my fragment "A", the values of edittext aren't refresh. Why?
I have this code to call fragment "B".
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_container_pedido_novo,
container, false);
btnAddProduto = (Button) view.findViewById(R.id.btnNovoProduto);
btnAddProduto.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Fragment fragment = new FragmentContainerProduto(true);
FragmentManager frgManager = getActivity()
.getSupportFragmentManager();
frgManager.beginTransaction()
.replace(R.id.content_frame, fragment)
.addToBackStack(null).commit();
}
});
edtCodPedido = (EditText) view.findViewById(R.id.edtCodPedidoNovo);
edtVlBruto = (EditText) view.findViewById(R.id.edtVlBrutoPedidoNovo);
edtCodPedido
.setText(String.valueOf(GlobalUtil.objPedido.getCodPedido()));
edtVlBruto.setText(String.valueOf(GlobalUtil.objPedido.getVlBruto()));
return view;
}
Someone?
When you return to a fragment from the back stack Android does not re-create the fragment but re-uses the same instance of it and starts with onCreateView() in the fragment lifecycle. The key thing is you should not inflate view again in onCreateView() of the fragment to which you return, because you are using the existing fragment instance. You need to save and reuse the rootView. See here the answer of Vince Yuan How can I maintain fragment state when added to the back stack?.
Well, I just need put this code...
#Override
public void onResume() {
super.onResume();
edtVlBruto.setText(String.valueOf(GlobalUtil.objPedido.getVlBruto()));
edtCodPedido
.setText(String.valueOf(GlobalUtil.objPedido.getCodPedido()));
}