my code
**I have a UserAdapter, and a Search Fragment and the user_item and user class. The problem is, the three Click Listeners to open the "Search Fragment " the app crashe!! and close.
i hope so i give u good explanation for the problem and thanks for the help in advance
**
public class SearchFragment extends Fragment {
private RecyclerView recyclerView;
private UserAdapter userAdapter;
private List<User> userList;
EditText search_bar;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_search, container, false);
recyclerView = view.findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
search_bar = view.findViewById(R.id.search_bar);
userList = new ArrayList<>();
userAdapter = new UserAdapter(getContext(), userList, true);
recyclerView.setAdapter(userAdapter);
readUsers();
search_bar.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
searchUsers(charSequence.toString().toLowerCase());
}
@Override
public void afterTextChanged(Editable editable) {
}
});
return view;
}
private void searchUsers(String s){
Query query = FirebaseDatabase.getInstance().getReference("Users").orderByChild("username")
.startAt(s)
.endAt(s+"\uf8ff");
query.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
userList.clear();
for (DataSnapshot snapshot : dataSnapshot.getChildren()){
User user = snapshot.getValue(User.class);
userList.add(user);
}
userAdapter.notifyDataSetChanged();
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
}
private void readUsers() {
final FirebaseUser firebaseUser = FirebaseAuth.getInstance().getCurrentUser();
DatabaseReference reference = FirebaseDatabase.getInstance().getReference("Users");
reference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
if (search_bar.getText().toString().equals("")) {
userList.clear();
for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
User user = snapshot.getValue(User.class);
userList.add(user);
}
userAdapter.notifyDataSetChanged();
}
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
}
}
** my code class Use**
public class User {
private String id;
private String username;
private String fullname;
private String imageurl;
private String bio;
public User(String id, String username, String fullname, String imageurl, String bio) {
this.id = id;
this.username = username;
this.fullname = fullname;
this.imageurl = imageurl;
this.bio = bio;
}
public User() {
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getFullname() {
return fullname;
}
public void setFullname(String fullname) {
this.fullname = fullname;
}
public String getImageurl() {
return imageurl;
}
public void setImageurl(String imageurl) {
this.imageurl = imageurl;
}
public String getBio() {
return bio;
}
public void setBio(String bio) {
this.bio = bio;
}
}
my code UserAdapter
public class UserAdapter extends RecyclerView.Adapter<UserAdapter.ImageViewHolder> {
private Context mContext;
private List<User> mUsers;
private boolean isFragment;
private FirebaseUser firebaseUser;
public UserAdapter(Context context, List<User> users, boolean isFragment){
mContext = context;
mUsers = users;
this.isFragment = isFragment;
}
@NonNull
@Override
public UserAdapter.ImageViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.user_item, parent, false);
return new UserAdapter.ImageViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull final UserAdapter.ImageViewHolder holder, final int position) {
firebaseUser = FirebaseAuth.getInstance().getCurrentUser();
final User user = mUsers.get(position);
holder.btn_follow.setVisibility(View.VISIBLE);
isFollowing(user.getId(), holder.btn_follow);
holder.username.setText(user.getUsername());
holder.fullname.setText(user.getFullname());
Glide.with(mContext).load(user.getImageurl()).into(holder.image_profile);
if (user.getId().equals(firebaseUser.getUid())){
holder.btn_follow.setVisibility(View.GONE);
}
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (isFragment) {
SharedPreferences.Editor editor = mContext.getSharedPreferences("PREFS", MODE_PRIVATE).edit();
editor.putString("profileid", user.getId());
editor.apply();
((FragmentActivity) mContext).getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new ProfileFragment()).commit();
} else {
Intent intent = new Intent(mContext, Main2Activity.class);
intent.putExtra("publisherid", user.getId());
mContext.startActivity(intent);
}
}
});
holder.btn_follow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (holder.btn_follow.getText().toString().equals("follow")) {
FirebaseDatabase.getInstance().getReference().child("Follow").child(firebaseUser.getUid())
.child("following").child(user.getId()).setValue(true);
FirebaseDatabase.getInstance().getReference().child("Follow").child(user.getId())
.child("followers").child(firebaseUser.getUid()).setValue(true);
addNotification(user.getId());
} else {
FirebaseDatabase.getInstance().getReference().child("Follow").child(firebaseUser.getUid())
.child("following").child(user.getId()).removeValue();
FirebaseDatabase.getInstance().getReference().child("Follow").child(user.getId())
.child("followers").child(firebaseUser.getUid()).removeValue();
}
}
});
}
private void addNotification(String userid){
DatabaseReference reference = FirebaseDatabase.getInstance().getReference("Notifications").child(userid);
HashMap<String, Object> hashMap = new HashMap<>();
hashMap.put("userid", firebaseUser.getUid());
hashMap.put("text", "started following you");
hashMap.put("postid", "");
hashMap.put("ispost", false);
reference.push().setValue(hashMap);
}
@Override
public int getItemCount() {
return mUsers.size();
}
public class ImageViewHolder extends RecyclerView.ViewHolder {
public TextView username;
public TextView fullname;
public CircleImageView image_profile;
public Button btn_follow;
public ImageViewHolder(View itemView) {
super(itemView);
username = itemView.findViewById(R.id.username);
fullname = itemView.findViewById(R.id.fullname);
image_profile = itemView.findViewById(R.id.image_profile);
btn_follow = itemView.findViewById(R.id.btn_follow);
}
}
private void isFollowing(final String userid, final Button button){
final FirebaseUser firebaseUser = FirebaseAuth.getInstance().getCurrentUser();
DatabaseReference reference = FirebaseDatabase.getInstance().getReference()
.child("Follow").child(firebaseUser.getUid()).child("following");
reference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
if (dataSnapshot.child(userid).exists()){
button.setText("following");
} else{
button.setText("follow");
}
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
}
}
** user_item**
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="8dp"
android:orientation="vertical">
<de.hdodenhof.circleimageview.CircleImageView
android:layout_width="50dp"
android:layout_height="50dp"
android:id="@+id/image_profile"
android:src="@mipmap/ic_launcher"/>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toEndOf="@+id/image_profile"
android:layout_marginStart="5dp"
android:orientation="vertical"
android:layout_centerVertical="true">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/username"
android:text="username"
android:maxLines="1"
android:textStyle="bold"
android:textColor="@color/colorPrimaryDark"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/fullname"
android:text="full_name"
android:maxLines="1"/>
</LinearLayout>
<Button
android:layout_width="wrap_content"
android:layout_height="30dp"
android:background="@drawable/button_background"
android:id="@+id/btn_follow"
android:textColor="@color/colorPrimary"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true"
android:visibility="gone"/>
</RelativeLayout>
stack trace
E/AndroidRuntime: FATAL EXCEPTION: main
Process: commenting, PID: 24881
java.lang.ClassCastException: androidx.appcompat.widget.AppCompatButton cannot be cast to androidx.recyclerview.widget.RecyclerView
at commenting.Fragment.SearchFragment.onCreateView(SearchFragment.java:47)
at androidx.fragment.app.Fragment.performCreateView(Fragment.java:2600)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManagerImpl.java:881)
at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManagerImpl.java:1238)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManagerImpl.java:1303)
at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:439)
at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManagerImpl.java:2079)
at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManagerImpl.java:1869)
at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManagerImpl.java:1824)
at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManagerImpl.java:1727)
at androidx.fragment.app.FragmentManagerImpl$2.run(FragmentManagerImpl.java:150)
at android.os.Handler.handleCallback(Handler.java:907)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:216)
at android.app.ActivityThread.main(ActivityThread.java:7625)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987)
I/Process: Sending signal. PID: 24881 SIG: 9
Fragment.SearchFragment
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Fragment.SearchFragment">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bar"
android:background="?android:attr/windowBackground">
<androidx.appcompat.widget.Toolbar
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?android:attr/windowBackground"
android:id="@+id/toolbar">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_search_light"/>
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/search_bar"
android:background="@android:color/transparent"
android:hint="search_bar"
android:layout_marginStart="10dp"
android:inputType="text"/>
</androidx.appcompat.widget.Toolbar>
</com.google.android.material.appbar.AppBarLayout>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/bar"
android:id="@+id/recycler_view"/>
</RelativeLayout>
