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Il existe une activité dans laquelle il existe un fragment, appelons-le FirstFragment. Il y a un framelayout dans ce fragment contenant un autre fragment, SecondFragment. En cliquant sur SecondFragment, ThirdFragment est tiré. Ici, je dois être en mesure de revenir au SecondFragment en appuyant sur le bouton de retour. Cependant, en cliquant sur le bouton de retour, l'activité est fermée. Voici mon code:Retour ne fonctionne pas dans le fragment interne
MainActivity.java
public class MainActivity extends AppCompatActivity{
ViewPager viewPager;
String[] titles;
SecondFragment secondFragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentPagerAdapter fragment = new FragmentPagerAdapter(getSupportFragmentManager());
viewPager = findViewById(R.id.viewPager);
viewPager.setAdapter(fragment);
firstFragment = new FirstFragment();
}
public class FragmentPagerAdapter extends android.support.v4.app.FragmentPagerAdapter {
public FragmentPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0 : return FirstFragment.newInstance("hi");
default: return new OtherFragment();
}
}
@Override
public int getCount() {
return 3;
}
}
@Override
public void onBackPressed() {
if (getFragmentManager().getBackStackEntryCount() > 0) {
getFragmentManager().popBackStack();
} else {
super.onBackPressed();
}
}
}
FirstFragment.java
public class FirstFragment extends Fragment implements RecyclerViewListener {
public FirstFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
Fragment secondFragment =SecondFragment.newInstance("hi");
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
transaction.replace(R.id.frameLayout, secondFragment).commit();
return inflater.inflate(R.layout.fragment_first, container, false);
}
public static FirstFragment newInstance(String text) {
FirstFragment f = new FirstFragment();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
@Override
public void clicked(int position) {
Fragment productDetailFragment = ThirdFragment.newInstance(position);
FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
transaction.add(R.id.frameLayout, productDetailFragment).addToBackStack(null).commit();
Toast.makeText(getContext(), "pos : " + position, Toast.LENGTH_SHORT).show();
}
@Override
public boolean longClicked(int position) {
return false;
}
}
SecondFragment.java
public class SecondFragment extends Fragment {
RecyclerView recyclerView;
static ArrayList<Item> items;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_second, container, false);
recyclerView = v.findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
items = new ArrayList<>();
for (int i = 0; i < 100; i++) {
Item item = new Item(R.drawable.accept_state, "esm" + i, Integer.toString(i * 100));
items.add(item);
}
recyclerView.setAdapter(new RecylcerViewAdapter(getContext(), (RecyclerViewListener) getParentFragment(), items));
return v;
}
public static SecondFragment newInstance(String text) {
SecondFragment f = new SecondFragment();
Bundle b = new Bundle();
b.putString("msg", text);
f.setArguments(b);
return f;
}
}
ThirdFragment.java
public class ThirdFragment extends android.support.v4.app.Fragment {
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_third, container, false);
return v;
}
public static ThirdFragment newInstance(int position) {
ThirdFragment f = new ThirdFragment();
Bundle b = new Bundle();
f.setArguments(b);
return f;
}
}
RecyclerViewListener.java
public interface RecyclerViewListener {
void clicked(int position);
boolean longClicked(int position);
}
RecyclerViewAdapter.java
public class RecylcerViewAdapter extends RecyclerView.Adapter<RecylcerViewAdapter.RecyclerViewHolder>{
private Context context;
private RecyclerViewListener recyclerViewListener;
private ArrayList<Item> items;
public RecylcerViewAdapter(Context context, RecyclerViewListener recyclerViewListener, ArrayList<Item> items) {
this.context = context;
this.recyclerViewListener = recyclerViewListener;
this.items = items;
}
@Override
public RecyclerViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.recycler_item, parent, false);
RecyclerViewHolder recyclerViewHolder = new RecyclerViewHolder(view);
return recyclerViewHolder;
}
@Override
public void onBindViewHolder(RecyclerViewHolder holder, int position) {
holder.bind(position);
}
@Override
public int getItemCount() {
return items.size();
}
public class RecyclerViewHolder extends RecyclerView.ViewHolder {
ImageView imageView;
TextView name;
TextView cost;
public RecyclerViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
recyclerViewListener.clicked(getAdapterPosition());
}
});
itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
return recyclerViewListener.longClicked(getAdapterPosition());
}
});
imageView = itemView.findViewById(R.id.image);
name = itemView.findViewById(R.id.name);
cost = itemView.findViewById(R.id.cost);
}
public void bind(int position) {
Item item = items.get(position);
imageView.setImageResource(item.getImageID());
name.setText(item.getName());
cost.setText(item.getCost());
}
}
}