Develop Reference

How to call fragment from the BottomSheetDialogFragment in android

I find it very difficult to call the InsertSlider in the MainFragment from the BottomSheetDialog.
Any help and thanks
In the BottomSheet :
public class AdminBottomSheetMainSave extends BottomSheetDialogFragment
{
// One Method I don.t Know How To Work
//((MainFragment)getContext()).InsertSliders(new ImageSlider(0,Name,Image,Price,Description));
// Not Work Too
MainFragment fragment = new MainFragment();
fragment.InsertSliders(new ImageSlider(0,Name,Image,Price,Description));
}
In the Fragment :
public class MainFragment extends Fragment
{
public void InsertSliders(ImageSlider imageSlider)
{
imageSliderViewModel.insert(imageSlider);
Toast.makeText(getActivity(), "Done Insert"+imageSlider, Toast.LENGTH_SHORT).show();
}
What is the contact method how do I get to InsertSliders

you should use interface to communicate between two fragments and you need an activity to implement the interface.
define interface in your bottomsheetdialogfragment:
public class AdminBottomSheetMainSave extends BottomSheetDialogFragment
{
public Callback mCallback;
public interface Callback{
void insertSlider(ImageSlider slider);
}
#Override
public void onAttach(Activity activity){
super.onAttach(activity);
mCallback = (Callback) activity;
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
//...
mCallback.insertSlider(new ImageSlider(0,Name,Image,Price,Description));
}
}
then in your activity in our case MainActivity implement Callback interface and override inserSlider method:
public class MainActivity extends AppCompatActivity implements Callback{
MainFragment mainFragment;
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//...
if(savedInstanceState == null){
mainFragment = MainFragment.newInstance(new Bundle()); // use real bundle here
getSupportFragmentManager()
.beginTransaction()
.add(R.id.fragment_holder, mainFragment, "FragMain").commit();
}
}
// Interface method
#Override
public void insertSlider(ImageSlider slider){
if(mainFragment != null){
mainFragment.insertSlider(slider);
}
}
now in your MainFragment:
public class MainFragment extends Fragment{
public static MainFragment newInstance(Bundle args){
MainFragment fragment = new MainFragment();
fragment.setArguments(args);
return fragment;
}
//... Class overrides here onCreateView etc..
// define insertSlider method
public void insertSlider(ImageSlider slider){
imageSliderViewModel.insert(slider);
Toast.makeText(getActivity(), "Done Insert"+slider, Toast.LENGTH_SHORT).show();
}

how to change fragment views programmatically from the parent activity

I am having a fragment that contains for example one button, I want to allow the Activity containing the fragment to change this button view like for example color and title or src Image.
What's the best way to do that ?
Update : sorry If I wasn't clear enough but I want the activity to change the whole view as it's likes , like setting the padding, the color or anything.
It will create the view programmatically and the fragment should replace the old view by the new one and change the view's ID so that the fragment code isn't affected. And If i created methods in the fragment that takes these views when should the Main activity call them ? since the activity has to wait for the layout of the fragment to be created.

1. You must get you fragment from your activity
val fragment = supportFragmentManager.findFragmentByTag("tag")
or
val fragment = supportFragmentManager.findFragmentById(R.id.fragment)
2. Create a method that will do what you wants in you fragment and call this method from the activity
fragment.hideButton()
or you can use interface

Try this way according to your requirement
public abstract class BaseFragment extends Fragment {
BaseActivity yourActivity;
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
yourActivity = (BaseActivity) context;
}
#Override
public void onDetach() {
yourActivity = null;
super.onDetach();
}
public void refreshview(){}
public void setDada(Data data){}
#override
publicn void onStart(){
yourActivity.setCurrentOpenedFragment(this);
}
}
Create the BaseActivity class
public abstract class BaseActivity extends AppCompatActivity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
public void setCurrentOpenedFragment(BaseFragment currentFragment){}
}
Extends the BaseFragment in your fragment i.e.
public class YourFragment extends BaseFragment{
View view;
Button button;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment, container, false);
button = (Button)view.findViewById(R.id.button);
return view;
}
#override
publicn void onStart(){
super.onStart();
//yourActivity.setCurrentOpenedFragment(this);
}
Data data;
#override
public void setDada(Data data){
this.data = data;
}
#Override
public void refreshview() {
button.setcolor(data.getcolor());
}
}
Write the below line of code in your Activity class
public class YourActivity extends BaseActivity{
public static final byte NONE = -1;
public static final byte HOME = 1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.your_activity);
changeFragment(new YourFragment(), HOME);
initview();
}
public void initview(){
Button b = (Button)findViewById(R.id.button);
b.setOnClickListener(new OnClickListener(){
if(currentFragmentOnDrawer != null){
Data data = new Data();
data.setColor(getResource().getcolor(R.color.red));
currentFragmentOnDrawer.setDada(data);
currentFragmentOnDrawer.refreshview()
}
});
}
BaseFragment currentFragmentOnDrawer;
#Override
public void setCurrentOpenedFragment(BaseFragment currentFragment) {
super.setCurrentOpenedFragment(currentFragment);
this.currentFragmentOnDrawer = currentFragment;
}
public void changeFragment(Fragment targetFragment, byte state) {
FragmentTransaction ft = getSupportFragmentManager()
.beginTransaction();
ft.replace(R.id.main_fragment, targetFragment, "" + state);
ft.addToBackStack("" + state);
ft.commit();
}
}
Hope it will help for you

Creating Multiple event callbacks from fragment to the activity

I was able to create a single event callback from a fragment to the activity. However, I have problem with creating two event callbacks from the same fragment.
Basically, I have a button on the fragment1 layout, when click on it, it will execute something in mainactivity, and then, it changes hide the Button at fragment1 layout, and then I need to send a Boolean from the fragment to activity, then initiate fragment2.
How can I implement the 2nd callback interface in the mainacativity.
Here is my code:
at Fragment1:
public class Fragment1 extends Fragment{
private static final String TAG = "Fragment1";
Boolean in1, in2;
Button btn1;
ListenerA mListenerA;
public interface ListenerA{
public void methodA(Boolean in1);
};
ListenerB mListenerB;
public interface ListenerB{
public void methodB(Boolean in2);
};
#Override
public void onAttach(Context context) {
super.onAttach(context);
if(context instanceof ListenerA)
mListenerA = (ListenerA)context;
if(context instanceof ListenerB)
mListenerB = (ListenerB)context;
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View myView = inflater.inflate(R.layout.fragment1, container, false);
btn1 = (Button) myView.findViewById(R.id.btn1_ID);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mListenerA.methodA(true);
}
});
return myView;
}
public void showBtnMethod (Boolean showBtn){
if (showBtn==false) {
btn1.setVisibility(View.INVISIBLE);
mListenerB.methodB(true); //***** problematic line
}
}
}
and the code in the main activity is below. please note that on the first line I was able only to implement one method from the fragment.
public class MainActivity extends AppCompatActivity implements Fragment1.ListenerA {
private static final String TAG = "MainActivity";
public Fragment1 mFragment1;
public Fragment2 mFragment2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
FragmentTransaction transaction1 = getSupportFragmentManager().beginTransaction();
mFragment1 = new Fragment1();
transaction1.replace(R.id.content_fragment_ID, mFragment1);
transaction1.commit();
}
}
// this gets called by ListenerA when click on the button
public void methodA(Boolean in){
if (in==true){
Toast.makeText(MainActivity.this, "mMethodA Executed", Toast.LENGTH_SHORT).show();
triggerShowMethod();
}
};
private void triggerShowMethod(){
mFragment1.showBtnMethod(false);
};
// Problematic section is below
public void methodB(Boolean in){
if (in==true){
FragmentTransaction transaction2 = getSupportFragmentManager().beginTransaction();
mFragment2 = new Fragment2();
transaction2.replace(R.id.content_fragment_ID, mFragment2);
transaction2.commit();
Toast.makeText(MainActivity.this, "mMethodB Executed", Toast.LENGTH_LONG).show();
}
};
}

You can simply consolidate both interfaces into one:
public interface Listener{
public void methodA(Boolean in1);
public void methodB(Boolean in2);
};
and in your MainActivity:
public class MainActivity extends AppCompatActivity implements Fragment1.Listener

Your activity doesn't implement ListenerB.
public class MainActivity extends AppCompatActivity implements Fragment1.ListenerA, Fragment1.ListenerB {
}

fragment callback using interface

I have an Activity that starts a Fragment. Inside that fragment i have an EditText. And when i get the text that the user types there, i want to get that from my Activity with the help of an interface. I'm using this guide
On my MainActivity i'm implementing the commentListener interface and i've managed to get the result inside the onCommentEntered method. But on doneListener, which is triggered when the user presses a button finishing the activity, i'm getting null.
Obviously onCommentEntered runs after doneListener.
Any suggestions on how to get the result on doneListener?
class MainActivity implements fragment.commentListener{
static String comment;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.addtransaction);
done=(TextView)findViewById(R.id.done_button);
}
// called when user presses a button and MainActivity finishes.
public void doneListener(View v){
// Here i get NULL
System.out.println(comment);
finish();
}
#Override
public void onCommentEntered(String data) {
comment=data;
// Here i get what the user typed
System.out.println(comment);
}
}
My fragment
public class thefragment extends Fragment {
commentListener cListener;
static TextView note;
EditText comment;
public interface commentListener{
void onCommentEntered(String data);
}
public static thefragment newInstance(){
return new thefragment ();
}
public thefragment (){
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
cListener=(commentListener) context;
}
#Override
public void onDetach() {
super.onDetach();
cListener=null;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v;
v=inflater.inflate(R.layout.fragment, container, false);
comment=(EditText)v.findViewById(R.id.comment_picker);
comment.setOnFocusChangeListener(new View.OnFocusChangeListener() {
#Override
public void onFocusChange(View v, boolean hasFocus) {
if (!hasFocus) {
cListener.onCommentEntered(comment.getText().toString());
}
}
});
return v;
}
}

Create a new Interface, as well as implement the same in Fragment. create a method in the interface and override the same in Fragments. While calling the fragment from Activity create an Interface type fragment and call the interface method.
eg:
public class thefragment extends Fragment implement fragmentNofyInterface {
...
#Override
protected void notify(String txt){
mTvTxt.setText(txt);
}
.....
}
Interface Format
public interface fragmentNofyInterface {
protected void notify(String txt);
}
Activity format
class MainActivity implements fragment.commentListener{
.....
private fragmentNofyInterface mFragmentNotifier;
.........
thefragment mFragment = new thefragment();
mFragmentNotifier = (fragmentNofyInterface ) mFragment;
FragmentTransaction transaction = mFragmentMngr.beginTransaction().
add(R.id.rl_fragment_navigation_container,
mFragment);
transaction .commit();
......
//Notify the fragment when you required
mFragmentNotifier.notify("hello world");
}

Switching to addTextChangedListener and TextWatcher for my EditText, like this here,
seems to fix my problem.Now onCommentEntered method is called before doneListener and thus String commentgets whatever was typed in the EditText.Thanks everyone for helping.

Comunicattion between fragments

I'm creating an app, and I have a doubt on how to communicate between fragments, I know I must communicate to the parent activity and etcetera my question is more best practice oriented. My app consists of a MainActivity with a navigation drawer which depending on the selection calls a fragment and puts it on the main screen.
I have 2 fragments which via a button need to call another fragment (I can convert it to an activity with no problem) that opens the camera to scan a barcode (BarScanFragment) (https://github.com/dm77/barcodescanner).
My question is it possible to know which fragment called the BarScanFragment so I can send the argument to the correct fragment, and how do I achieve it.
BarScanFragment.java
public class BarScanFragment extends Fragment implements ZXingScannerView.ResultHandler{
private ZXingScannerView mScannerView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
mScannerView = new ZXingScannerView(getActivity());
return mScannerView;
}
#Override
public void onResume() {
super.onResume();
mScannerView.setResultHandler(this);
mScannerView.startCamera();
}
#Override
public void onPause() {
super.onPause();
mScannerView.stopCamera();
}
#Override
public void handleResult(Result result) {
Log.i("TAG", result.getText());
Bundle args = new Bundle();
args.putString("barcodeScan", result.getText());
}
FragmentA.java
......
......
barcodeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Fragment content = new BarScanFragment();
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.flFragmentContainer, content).addToBackStack("TRADEIN")
.commit();
/*Intent intent = new Intent(rootView.getContext(), BarcodeScannerActivity.class);
startActivity(intent);*/
}
});
Fragment b.java
.....
.....
barcodeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Fragment content = new BarScanFragment();
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.flFragmentContainer, content).addToBackStack("INFOPRODUCT")
.commit();
/*Intent intent = new Intent(rootView.getContext(), BarcodeScannerActivity.class);
startActivity(intent);*/
}
});

Take a look on setTargetFragment and getTargetFragment. It's the easiest way to communicate back and forth between fragment.
Here there is a little example https://github.com/alexfu/TargetFragmentExample

You can add a parameter to the BarScanFragment's constructor:
public BarScanFragment(int creatorFragment) {
// Do something with creatorFragment
}
Save "creatorFragment" values in your activity:
public static final int FRAGMENT_1 = 0;
public static final int FRAGMENT_2 = 1;
Then in your button listeners create the BarScanFragment with a specific value:
Fragment content = new BarScanFragment(MainActivity.FRAGMENT_1);
or
Fragment content = new BarScanFragment(MainActivity.FRAGMENT_2);

Declare callbacks in your activity and call methods from another fragment using these callbacks
public interface Callback1 {
void callbackMethod1();
}
public interface Callback2 {
void callbackMethod2();
}
public class Activity extends ActionBarActivity implements Callback1, Callback2 {
Fragment1 mFragment1;
Fragment2 mFragment2;
#Override
public void callbackMethod1() {
mFragment2.method2();
}
#Override
public void callbackMethod2() {
mFragment1.method1();
}
}
public class Fragment1 extends Fragment {
Callback1 callback;
#Override
public void onAttach(android.app.Activity activity) {
super.onAttach(activity);
callback = (Callback1) getActivity();
}
void callMethodOfFragment1() {
callback.callbackMethod1();
}
#Override
public void onDetach() {
super.onDetach();
callback = null;
}
public void method1() {
do_sth_in_fr2();
}
}
public class Fragment2 extends Fragment {
Callback2 callback;
#Override
public void onAttach(android.app.Activity activity) {
super.onAttach(activity);
callback = (Callback2) getActivity();
}
void callMethodOfFragment2() {
callback.callbackMethod2();
}
#Override
public void onDetach() {
super.onDetach();
callback = null;
}
public void method2() {
do_sth_in_fr1();
}
}