Java RecyclerView不在片段中显示项，但在活动中工作
免责声明：在搜索了整个StackOverflow之后，我还没有找到解决方案Java RecyclerView不在片段中显示项，但在活动中工作,java,android,android-fragments,android-recyclerview,android-adapter,Java,Android,Android Fragments,Android Recyclerview,Android Adapter,免责声明：在搜索了整个StackOverflow之后，我还没有找到解决方案 我以前曾在另一个活动中成功地使用过RecyclerView，因此我将该代码移植到一个片段中。我不知道为什么这些物品没有出现在RecyclerView中。调试后，Fragment\u\u Activities类似乎没有调用ActivitiesAdapter方法，例如onBindViewHolder（）和onCreateViewHolder（） Fragment\u即将到来的活动。java: private Fire
我以前曾在另一个活动中成功地使用过RecyclerView，因此我将该代码移植到一个片段中。我不知道为什么这些物品没有出现在RecyclerView中。调试后，Fragment\u\u Activities类似乎没有调用ActivitiesAdapter方法，例如onBindViewHolder（）和onCreateViewHolder（） Fragment\u即将到来的活动。java:
private FirebaseAuth fAuth;
private FirebaseFirestore fStore;
private FirebaseUser mFirebaseUser;
private RecyclerView mFirestoreList;
private String currentUid;
private CollectionReference catRef;
private List<String> list_category = new ArrayList();
private ArrayAdapter<String> adapter_category;
private Spinner spCategories;
private ActivitiesAdapter adapter;
private View view;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container, @NonNull Bundle savedInstanceState) {
fAuth = FirebaseAuth.getInstance();
mFirebaseUser = fAuth.getCurrentUser();
fStore = FirebaseFirestore.getInstance();
currentUid = mFirebaseUser.getUid();
return inflater.inflate(R.layout.fragment_upcoming_activity, container, false);
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
spCategories = view.findViewById(R.id.category_spinner);
mFirestoreList = view.findViewById(R.id.upcoming_act_recycleView);
//setUpCategoriesSpinner();
setupRecyclerView();
}
public void setUpCategoriesSpinner(){
//Department spinner population
catRef = fStore.collection("parent_categories");
list_category = new ArrayList<>();
adapter_category = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_spinner_item, list_category);
adapter_category.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spCategories.setAdapter(adapter_category);
spCategories.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selected = (String) parent.getSelectedItem();
displayUserData(selected);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
catRef.get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
@Override
public void onComplete(@NonNull Task<QuerySnapshot> task) {
if (task.isSuccessful()) {
for (QueryDocumentSnapshot document : task.getResult()) {
String categoryName = document.getString("category_name");
list_category.add(categoryName);
}
adapter_category.notifyDataSetChanged();
}
}
});
}
public void displayUserData(String selected){
System.out.println("Selected category: " + selected);
Query query;
if (selected.equals("All Categories")) {
System.out.println("ALL");
query = fStore.collection("activities").whereEqualTo("act_purpose", "All");
} else {
System.out.println("OTHER");
String sub = selected.substring(selected.length() - 1);
System.out.println(sub);
int catNo = Integer.parseInt(sub);
query = fStore.collection("activities").whereEqualTo("act_purpose", "All").whereGreaterThan("act_category_number", sub).whereLessThan("act_category_number", sub).orderBy("act_category_number", Query.Direction.DESCENDING).orderBy("start_date", Query.Direction.DESCENDING);
}
//RecyclerOptions
FirestoreRecyclerOptions<ActivitiesModel> options = new FirestoreRecyclerOptions.Builder<ActivitiesModel>()
.setQuery(query, ActivitiesModel.class)
.build();
//View Holder
adapter.updateOptions(options);
}
private void setupRecyclerView(){
Query query = fStore.collection("activities");
//RecyclerOptions
FirestoreRecyclerOptions<ActivitiesModel> options = new FirestoreRecyclerOptions.Builder<ActivitiesModel>()
.setQuery(query, ActivitiesModel.class)
.build();
//View Holder
adapter = new ActivitiesAdapter(options);
mFirestoreList.setLayoutManager(new LinearLayoutManager(getContext()));
mFirestoreList.setAdapter(adapter);
adapter.setOnItemClickListener(new ActivitiesAdapter.OnItemClickListener() {
@Override
public void onItemClick(DocumentSnapshot documentSnapshot, int position) {
}
});
}
private ActivitiesAdapter.OnItemClickListener listener;
public ActivitiesAdapter(@NonNull FirestoreRecyclerOptions<ActivitiesModel> options) {
super(options);
}
@Override
protected void onBindViewHolder(@NonNull ActivitiesAdapter.ActivitiesHolder holder, int position, @NonNull ActivitiesModel model) {
String temp = model.getStart_date().toString().trim();
String[] temparray = temp.split(" ");
String startMonth = temparray[1];
String startDate = temparray[2];
String startYear = temparray[5];
String act_title = model.getAct_title();
String act_catName = model.getAct_category_name();
String pdHoursAndPoints = model.getPoints() + " Points · " + model.getHours() + " Hours";
holder.actTitle.setText(act_title);
holder.startDate.setText(startDate + "\n" + startMonth + "\n" + startYear);
holder.actCategory.setText(act_catName);
holder.actPointsAndHours.setText(pdHoursAndPoints);
}
@NonNull
@Override
public ActivitiesAdapter.ActivitiesHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_actlog,
parent, false);
return new ActivitiesAdapter.ActivitiesHolder(v);
}
class ActivitiesHolder extends RecyclerView.ViewHolder {
private TextView startDate, actTitle, actCategory, actPointsAndHours;
public ActivitiesHolder(View itemView) {
super(itemView);
startDate = itemView.findViewById(R.id.textview_startdate);
actTitle = itemView.findViewById(R.id.textview_act_title);
actCategory = itemView.findViewById(R.id.textview_act_category);
actPointsAndHours = itemView.findViewById(R.id.textview_pointsandhours_act);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int position = getAdapterPosition();
if(position != RecyclerView.NO_POSITION && listener != null){
listener.onItemClick(getSnapshots().getSnapshot(position),position);
//insert intent for edit here
}
}
});
}
}
public interface OnItemClickListener{
void onItemClick(DocumentSnapshot documentSnapshot, int position);
}
public void setOnItemClickListener(ActivitiesAdapter.OnItemClickListener listener){
this.listener = listener;
}
私有FirebaseAuth fAuth；
私人FirebaseFirestore商店；
私有FirebaseUser mFirebaseUser；
私人RecyclerView mFirestoreList；
私有字符串currentUid；
私人收藏参考catRef；
private List_category=new ArrayList（）；
专用阵列适配器_类；
私有微调器类别；
私有活动适配器；
私人视野；
@可空
@凌驾
创建视图时的公共视图（@NonNull LayoutInflater inflater、@NonNull ViewGroup container、@NonNull Bundle savedInstanceState）{
fAuth=FirebaseAuth.getInstance（）；
mFirebaseUser=fAuth.getCurrentUser（）；
fStore=FirebaseFirestore.getInstance（）；
currentUid=mFirebaseUser.getUid（）；
返回充气机。充气（R.layout.fragment\u即将进行的\u活动，容器，错误）；
}
@凌驾
已创建视图上的公共void（视图，@Nullable Bundle savedInstanceState）{
super.onViewCreated（视图，savedInstanceState）；
spCategories=view.findviewbyd（R.id.categories\u微调器）；
mFirestoreList=view.findViewById（R.id.coming\u act\u recycleView）；
//setupCategoriesPinner（）；
setupRecyclerView（）；
}
public void setupCategoriesPinner（）{
//部门微调器总体
catRef=fStore.collection（“父类别”）；
list_category=new ArrayList（）；
adapter\u category=new ArrayAdapter（getActivity（），android.R.layout.simple\u微调器\u项，列表\u类别）；
adapter\u category.setDropDownViewResource（android.R.layout.simple\u微调器\u下拉菜单\u项）；
spCategories.setAdapter（适配器\ U类）；
spCategories.setOnItemSelectedListener（新的AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView父视图、视图视图、整型位置、长id）{
所选字符串=（字符串）父级。getSelectedItem（）；
显示用户数据（选中）；
}
@凌驾
未选择公共无效（AdapterView父级）{
}
});
catRef.get（）.addOnCompletListener（新的OnCompletListener（））{
@凌驾
未完成的公共void（@NonNull任务）{
if（task.issusccessful（））{
对于（QueryDocumentSnapshot文档：task.getResult（））{
String categoryName=document.getString（“category_name”）；
列表\类别。添加（类别名称）；
}
适配器_category.notifyDataSetChanged（）；
}
}
});
}
public void displayUserData（已选择字符串）{
System.out.println（“所选类别：+所选类别”）；
查询；
如果（选定。等于（“所有类别”））{
系统输出打印项次（“全部”）；
query=fStore.collection（“活动”）。其中equalto（“行为目的”、“全部”）；
}否则{
系统输出打印项次（“其他”）；
String sub=selected.substring（selected.length（）-1）；
系统输出打印项次（sub）；
int catNo=Integer.parseInt（sub）；
query=fStore.collection（“activities”）.whereEqualTo（“act\u purpose”、“All”）.wheregreether（“act\u category\u number”，sub）.whereLessThan（“act\u category\u number”，sub）.orderBy（“act\u category\u number”，query.Direction.DESCENDING”）.orderBy（“开始日期”，query.Direction.DESCENDING”）；
}
//回收选项
FirestoreRecyclerOptions选项=新建FirestoreRecyclerOptions.Builder（）
.setQuery（查询，ActivitiesModel.class）
.build（）；
//视图持有者
adapter.updateOptions（选项）；
}
私有void setupRecyclerView（）{
Query=fStore.collection（“活动”）；
//回收选项
FirestoreRecyclerOptions选项=新建FirestoreRecyclerOptions.Builder（）
.setQuery（查询，ActivitiesModel.class）
.build（）；
//视图持有者
适配器=新活动适配器（选项）；
setLayoutManager（新的LinearLayoutManager（getContext（））；
mFirestoreList.setAdapter（适配器）；
setOnItemClickListener（新活动adapter.OnItemClickListener（）{
@凌驾
public void onItemClick（DocumentSnapshot DocumentSnapshot，int位置）{
}
});
}
private FirebaseAuth fAuth;
private FirebaseFirestore fStore;
private FirebaseUser mFirebaseUser;
private RecyclerView mFirestoreList;
private String currentUid;
private CollectionReference catRef;
private List<String> list_category = new ArrayList();
private ArrayAdapter<String> adapter_category;
private Spinner spCategories;
private ActivitiesAdapter adapter;
private View view;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @NonNull ViewGroup container, @NonNull Bundle savedInstanceState) {
fAuth = FirebaseAuth.getInstance();
mFirebaseUser = fAuth.getCurrentUser();
fStore = FirebaseFirestore.getInstance();
currentUid = mFirebaseUser.getUid();
return inflater.inflate(R.layout.fragment_upcoming_activity, container, false);
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
spCategories = view.findViewById(R.id.category_spinner);
mFirestoreList = view.findViewById(R.id.upcoming_act_recycleView);
//setUpCategoriesSpinner();
setupRecyclerView();
}
public void setUpCategoriesSpinner(){
//Department spinner population
catRef = fStore.collection("parent_categories");
list_category = new ArrayList<>();
adapter_category = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_spinner_item, list_category);
adapter_category.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spCategories.setAdapter(adapter_category);
spCategories.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
String selected = (String) parent.getSelectedItem();
displayUserData(selected);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
catRef.get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
@Override
public void onComplete(@NonNull Task<QuerySnapshot> task) {
if (task.isSuccessful()) {
for (QueryDocumentSnapshot document : task.getResult()) {
String categoryName = document.getString("category_name");
list_category.add(categoryName);
}
adapter_category.notifyDataSetChanged();
}
}
});
}
public void displayUserData(String selected){
System.out.println("Selected category: " + selected);
Query query;
if (selected.equals("All Categories")) {
System.out.println("ALL");
query = fStore.collection("activities").whereEqualTo("act_purpose", "All");
} else {
System.out.println("OTHER");
String sub = selected.substring(selected.length() - 1);
System.out.println(sub);
int catNo = Integer.parseInt(sub);
query = fStore.collection("activities").whereEqualTo("act_purpose", "All").whereGreaterThan("act_category_number", sub).whereLessThan("act_category_number", sub).orderBy("act_category_number", Query.Direction.DESCENDING).orderBy("start_date", Query.Direction.DESCENDING);
}
//RecyclerOptions
FirestoreRecyclerOptions<ActivitiesModel> options = new FirestoreRecyclerOptions.Builder<ActivitiesModel>()
.setQuery(query, ActivitiesModel.class)
.build();
//View Holder
adapter.updateOptions(options);
}
private void setupRecyclerView(){
Query query = fStore.collection("activities");
//RecyclerOptions
FirestoreRecyclerOptions<ActivitiesModel> options = new FirestoreRecyclerOptions.Builder<ActivitiesModel>()
.setQuery(query, ActivitiesModel.class)
.build();
//View Holder
adapter = new ActivitiesAdapter(options);
mFirestoreList.setLayoutManager(new LinearLayoutManager(getContext()));
mFirestoreList.setAdapter(adapter);
adapter.setOnItemClickListener(new ActivitiesAdapter.OnItemClickListener() {
@Override
public void onItemClick(DocumentSnapshot documentSnapshot, int position) {
}
});
}
private ActivitiesAdapter.OnItemClickListener listener;
public ActivitiesAdapter(@NonNull FirestoreRecyclerOptions<ActivitiesModel> options) {
super(options);
}
@Override
protected void onBindViewHolder(@NonNull ActivitiesAdapter.ActivitiesHolder holder, int position, @NonNull ActivitiesModel model) {
String temp = model.getStart_date().toString().trim();
String[] temparray = temp.split(" ");
String startMonth = temparray[1];
String startDate = temparray[2];
String startYear = temparray[5];
String act_title = model.getAct_title();
String act_catName = model.getAct_category_name();
String pdHoursAndPoints = model.getPoints() + " Points · " + model.getHours() + " Hours";
holder.actTitle.setText(act_title);
holder.startDate.setText(startDate + "\n" + startMonth + "\n" + startYear);
holder.actCategory.setText(act_catName);
holder.actPointsAndHours.setText(pdHoursAndPoints);
}
@NonNull
@Override
public ActivitiesAdapter.ActivitiesHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_actlog,
parent, false);
return new ActivitiesAdapter.ActivitiesHolder(v);
}
class ActivitiesHolder extends RecyclerView.ViewHolder {
private TextView startDate, actTitle, actCategory, actPointsAndHours;
public ActivitiesHolder(View itemView) {
super(itemView);
startDate = itemView.findViewById(R.id.textview_startdate);
actTitle = itemView.findViewById(R.id.textview_act_title);
actCategory = itemView.findViewById(R.id.textview_act_category);
actPointsAndHours = itemView.findViewById(R.id.textview_pointsandhours_act);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int position = getAdapterPosition();
if(position != RecyclerView.NO_POSITION && listener != null){
listener.onItemClick(getSnapshots().getSnapshot(position),position);
//insert intent for edit here
}
}
});
}
}
public interface OnItemClickListener{
void onItemClick(DocumentSnapshot documentSnapshot, int position);
}
public void setOnItemClickListener(ActivitiesAdapter.OnItemClickListener listener){
this.listener = listener;
}
private Activities Adapter.OnItemClickListener侦听器；
公共活动适配器（@NonNull FirestoreRecyclerOptions选项）{
超级（期权）；
}
@凌驾
BindViewHolder上受保护的无效（@NonNull ActivitiesAdapter.ActivitiesHolder holder，int位置，@NonNull ActivitiesModel模型）{
字符串temp=model.getStart_date（）.toString（）.trim（）；
字符串[]temparray=temp.split（“”）；
字符串startMonth=temparray[1]；
字符串startDate=temparray[2]；
字符串startYear=temparray[5]；
字符串act_title=model.getAct_title（）；
字符串act_catName=model.getAct_category_name（）；
字符串pdHoursAndPoints=model.getPoints（）+“Points·”+model.getHours（）+“Hours”；
持有人.actTitle.setText（法案标题）；
holder.startDate.setText（startDate+“\n”+startMonth+“\n”+startYear）；
holder.actCategory.setText（act_catName）；
holder.ac