我正在尝试增加负载。 我尝试应用我要搜索的内容，但没有成功。
这是我的代码。 最新成绩 fragment
public class LatestGradeFragment extends Fragment implements SwipeRefreshLayout.OnRefreshListener{
List<ListGradeData> sectionList;
RecyclerView recyclerView;
SwipeRefreshLayout mSwipeRefreshLayout;
public static LatestGradeFragment newInstance() {
return new LatestGradeFragment();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_latest_grade, container, false);
//RecyclerView+CardView for section
recyclerView = (RecyclerView) rootView.findViewById(R.id.display_recyclerView);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
sectionList = new ArrayList<>();
mSwipeRefreshLayout = (SwipeRefreshLayout) rootView.findViewById(R.id.swipeRefreshSection);
mSwipeRefreshLayout.setOnRefreshListener(this);
mSwipeRefreshLayout.setColorSchemeResources(R.color.colorPrimary,
android.R.color.holo_green_dark,
android.R.color.holo_orange_dark,
android.R.color.holo_blue_dark);
mSwipeRefreshLayout.post(new Runnable() {
@Override
public void run() {
mSwipeRefreshLayout.setRefreshing(true);
// Fetching data from server
loadSection();
}
});
return rootView;
}
@Override
public void onRefresh() {
loadSection();
}
private void loadSection() {
mSwipeRefreshLayout.setRefreshing(true);
StringRequest stringRequest = new StringRequest(Request.Method.GET, Constants.USER_GRADE,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
//converting the string to json array object
JSONArray array = new JSONArray(response);
if(sectionList!=null) {
sectionList.clear();
}
//traversing through all the object
for (int i = 0; i < array.length(); i++) {
//getting product object from json array
JSONObject sections = array.getJSONObject(i);
//adding the product to product list
sectionList.add(new ListGradeData(
sections.getInt("id"),
sections.getString("section"),
sections.getString("level"),
sections.getString("schoolyear")
));
}
//creating adapter object and setting it to recyclerview
LatestGradeAdapter adapter = new LatestGradeAdapter(getActivity(), sectionList);
recyclerView.setAdapter(adapter);
} catch (JSONException e) {
e.printStackTrace();
}
// Stopping swipe refresh
mSwipeRefreshLayout.setRefreshing(false);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
// Stopping swipe refresh
mSwipeRefreshLayout.setRefreshing(false);
}
});
//adding our stringrequest to queue
Volley.newRequestQueue(getActivity().getApplicationContext()).add(stringRequest);
}
@Override
public String toString() {
return "LatestGradeFragment";
}
}`
这是我的 LatestGradeAdapter:
public class LatestGradeAdapter extends RecyclerView.Adapter<LatestGradeAdapter.RecyclerViewHolder> {
private Context mCtx;
private List<ListGradeData> sectionList;
`public LatestGradeAdapter(Context mCtx, List<ListGradeData> sectionList) {
this.mCtx = mCtx;
this.sectionList = sectionList;
}
@NonNull
@Override
public RecyclerViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(mCtx);
View view = inflater.inflate(R.layout.section_data_list, parent, false);
return new LatestGradeAdapter.RecyclerViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull RecyclerViewHolder holder, int position) {
final ListGradeData sections = sectionList.get(position);
//BIND DATA
holder.textViewSection.setText(sections.getSection());
holder.textViewLevel.setText(sections.getLevel());
holder.textViewSchoolYear.setText(sections.getSchoolyear());
}
@Override
public int getItemCount() {
return sectionList.size();
}
public class RecyclerViewHolder extends RecyclerView.ViewHolder {
//Variables for list
TextView textViewSection, textViewLevel, textViewSchoolYear;
//Variables for head section
TextView textHeaderSection, textHeaderLevel, textHeaderSchoolYear;
public RecyclerViewHolder(final View itemView) {
super(itemView);
textViewSection = (TextView) itemView.findViewById(R.id.textSection);
textViewLevel = (TextView) itemView.findViewById(R.id.textLevel);
textViewSchoolYear = (TextView) itemView.findViewById(R.id.textYear);
}
}
}`
最佳答案
在您的 LatestGradeFragment.class 中添加此代码
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
int lastVisiblePosition = layoutManager.findLastVisibleItemPosition();
if (lastVisiblePosition == recyclerView.getChildCount()) {
progrssBar.setVisibility(View.VISIBLE);
loadMore(); //This methos is used for load next set of items.
}
}
});
public void loadMore(){
//load next set of items to adapter
adapter.notifyDataSetChanged();
progrssBar.setVisibility(View.GONE);
}
像这样创建你的 fragment_latest_grade:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="@id/progressBar" />
<ProgressBar
android:id="@+id/progressBar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerInParent="true"
android:visibility="gone" />
</RelativeLayout>
关于android - 如何在我的 fragment 和适配器中添加更多负载，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/51297177/