问题
I followed the recyclerview guidelines and built one for the app I am making, but it does not scroll to the bottom for some reason. I compared it with google code snippets, as well as other code snippets online and can't see the difference. I have posted a picture and the code I am using. I am using tabs, therefore the recyclerview is populated in a fragment.
What the app looks like:
http://imgur.com/H5uOLFR
the adapter class:
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private List<Group> groups;
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView groupName;
public TextView groupDate;
public TextView groupLocation;
public TextView className;
public ViewHolder(View v) {
super(v);
groupName = (TextView) v.findViewById(R.id.groupName);
groupDate = (TextView) v.findViewById(R.id.groupDate);
groupLocation = (TextView) v.findViewById(R.id.groupLocation);
className = (TextView) v.findViewById(R.id.className);
}
}
/*
* TODO: finish this method
*/
public void add(int position, String item) {
notifyItemInserted(position);
}
public void remove(String item) {
int position = groups.indexOf(item);
groups.remove(position);
notifyItemRemoved(position);
}
// Provide a suitable constructor (depends on the kind of dataset)
public MyAdapter(List<Group> groupsList) {
groups = groupsList;
Log.d("TEST", "Number of Groups: " +
Integer.toString(groups.size()));
}
// Create new views (invoked by the layout manager)
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
int viewType) {
// create a new view
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.group_view, parent, false);
// set the view's size, margins, paddings and layout parameters
ViewHolder vh = new ViewHolder(v);
return vh;
}
// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
// - get element from your dataset at this position
// - replace the contents of the view with that element
final Group group = groups.get(position);
// holder.groupName.setText(group.getName());
holder.groupName.setText(group.getName());
holder.groupDate.setText(group.getFormattedDate());
holder.groupLocation.setText(group.getLocation());
holder.className.setText(group.getParent().getName());
}
// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
return groups.size();
}
}
The Fragment class:
public class groupsFragment extends Fragment implements GroupLeaver, GroupRetriever {
private RecyclerView rv;
private List<Group> groups;
private ProgressDialog progressDialog;
@Override
public void onCreate(Bundle savedInstance){
super.onCreate(savedInstance);
Log.d("TEST", "Entered onCreate");
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
AppMain.getController().retrieveGroups(groupsFragment.this);
Log.d("TEST", "Entered onCreateView");
View rootView = inflater.inflate(R.layout.groups_fragment, container, false);
rv = (RecyclerView) rootView.findViewById(R.id.recyclerView);
rv.setLayoutManager(new LinearLayoutManager(getActivity()));
Log.d("TEST", "Size of LIST: " + Integer.toString(groups.size()));
MyAdapter adapter = new MyAdapter(groups);
rv.setAdapter(adapter);
return rootView;
}
@Override
public void onMyGroupsFound(List<Group> groups) {
Log.d("TEST", "Entered onMyGroupsFound");
Logg.info(this.getClass(), "Found %d groups for member %s", groups.size(), User.getCurrentUser().getDisplayName());
this.groups = groups;
}
@Override
public void onGroupLeft(Group oldGroup) {
}
@Override
public void onGroupLeftFailed(Group group, ParseException e) {
}
}
The xml layout for the recyclerview:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<android.support.v7.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:divider="@null"/>
</FrameLayout>
The xml layout for the recyclerview items:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
android:orientation="horizontal">
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="0dp"
android:layout_weight="3"
android:orientation="vertical">
<TextView
android:id="@+id/groupName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Group Name"
/>
<TextView
android:id="@+id/groupDate"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Group Date"
/>
<TextView
android:id="@+id/groupLocation"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Group Location"
/>
</LinearLayout>
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="0dp"
android:layout_weight="1"
android:orientation="vertical">
<TextView
android:id="@+id/className"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="right"
android:text="Class Name"
/>
</LinearLayout>
</LinearLayout>
</FrameLayout>
回答1:
You can use these lines to scroll recyclerview to:
list.add(0, group);
adapter.notifyItemInserted(0);
recyclerview.scrollToPosition(0);
回答2:
Thanks to everyone who responded, but turns out the problem was the version of RecyclerView I was compiling.
Previously I was compiling this
compile 'com.android.support:recyclerview-v7:22.0.0'
But I changed it to this and it worked
compile 'com.android.support:recyclerview-v7:22.2.0'
Credits to @roi divon for the answer: CoordinatorLayout with RecyclerView & CollapsingToolbarLayout
回答3:
Maybe adding these lines to the recyclerView will do:
android:scrollbarAlwaysDrawVerticalTrack="true"
android:scrollbars="vertical"
This is my recyclerView which is working:
<android.support.v7.widget.RecyclerView
android:id="@+id/menuRecycler"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbarAlwaysDrawVerticalTrack="true"
android:scrollbars="vertical"/>
回答4:
I am not sure but I think problem might be Framelayout You can try with Linearlayout instead of Framelayout in your xml layout for the recyclerview items
来源：https://stackoverflow.com/questions/31979858/recyclerview-not-scrolling-to-the-bottom