Question

我无法弄清楚为什么我的RecyclerView的第一行只显示空的xml-Layout。

就像该行的数据是空的一样。但我得到4行 - 即使我只有3行数据记录。。（行大小用“data-record”-List.size（）;）

指定

无论如何，我正在寻找一种解决方法。有谁知道如何只删除Recycler View的第一行？我是否只需要删除“data-record”列表的第一项？

问候约翰

编辑代码：

VotingHistoryFragment.java：

public class VotingHistoryFragment extends Fragment implements VotingHistoryAdapter.ClickListener{

private Realm realm;
private FragmentStateHandler fragmentStateHandler;
private Backend backend;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
    super.onCreateView(inflater, container, savedInstanceState);
    View layout = inflater.inflate(R.layout.voting_history_fragment_layout, container, false);
    HotFixRecyclerView hotFixRecyclerView = (HotFixRecyclerView) layout.findViewById(R.id.votingHistoryDrawerList);
    realm = Realm.getInstance(getActivity());
    fragmentStateHandler = FragmentStateHandler.getInstance();
    backend = Backend.getInstance();

    VotingHistoryAdapter votingHistoryAdapter = new VotingHistoryAdapter(getActivity());
    votingHistoryAdapter.setClickListener(this);
    hotFixRecyclerView.setAdapter(votingHistoryAdapter);
    hotFixRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
    return layout;
}

private RealmList<Voting> getVotingList() {
    RealmList<Voting> votingList = new RealmList<>();
    votingList.addAll(realm.where(Voting.class).equalTo(Constants.TAG_STATUS, false).findAllSorted(Constants.TAG_TIMESTAMP));
    return votingList;
}

@Override
public void itemClicked(View view, int position) {
    try {
        Voting current = getVotingList().get(position);
        Bundle b = new Bundle();
        b.putString(Constants.TAG_OWNER_ID, backend.loggedOwner.getId());
        b.putString(Constants.TAG_VOTING_ID, current.getId());
        fragmentStateHandler.replaceFrag(Frag.ARCHIVEDVOTINGFRAGMENT, b);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
public void onPause() {
    super.onPause();
    SharedPreferences prefs = getActivity().getSharedPreferences("X", Context.MODE_PRIVATE);
    SharedPreferences.Editor editor = prefs.edit();
    editor.putString("lastActivity", getClass().getName());
    editor.apply();
}
}

VotingHistoryAdapter.java：

public class VotingHistoryAdapter extends HotFixRecyclerView.Adapter <VotingHistoryAdapter.votingHistoryViewHolder>{
private final LayoutInflater    inflater;
private final RealmList<Voting> votingList;
private ClickListener   clickListener;
private final Realm     realm;
private int             increment;

public VotingHistoryAdapter(Context context) {
    inflater = LayoutInflater.from(context);
    realm = Realm.getInstance(context);
    realm.setAutoRefresh(false);

    // query votings
    RealmQuery<Voting> votingRealmQuery = realm.where(Voting.class);
    votingList = new RealmList<>();
    votingList.addAll(votingRealmQuery.equalTo("status", false).findAll());
    increment = 0;

}

@Override
public votingHistoryViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = inflater.inflate(R.layout.voting_history_row, parent, false);

    return new votingHistoryViewHolder(view);
}

@Override
public void onBindViewHolder(votingHistoryViewHolder holder, int position) {
    Voting current = votingList.get(position);

    RealmList<Idea> ideaRealmList = new RealmList<>();
    ideaRealmList.addAll(realm.where(Idea.class).equalTo(Constants.TAG_VOTING_ID, current.getId()).findAllSorted(Constants.TAG_VOTECOUNT, false));
    Idea winnerIdea = ideaRealmList.first();
    Calendar calendar = Calendar.getInstance();
    calendar.setTimeInMillis(current.getTimeStamp());

    int mYear = calendar.get(Calendar.YEAR);
    int mMonth = calendar.get(Calendar.MONTH);
    int mDay = calendar.get(Calendar.DAY_OF_MONTH);

    if(winnerIdea==null){Log.d("winnerIdea ", "Idea is null");  return;}

    try {
        Log.d("winnerIdea ", "position:" + position);
        Log.d("winnerIdea ", "titel:" + winnerIdea.getText());
        Log.d("winnerIdea ", "text:" + winnerIdea.getText());
        Log.d("winnerIdea ", "tag1:" + winnerIdea.getTags().get(0).getText());
        Log.d("winnerIdea ", "tag2:" + winnerIdea.getTags().get(1).getText());
        Log.d("winnerIdea ", "tag3:" + winnerIdea.getTags().get(2).getText());
        Log.d("winnerIdea ", "tag4:" + winnerIdea.getTags().get(3).getText());
        Log.d("winnerIdea ", "besitzer: " + winnerIdea.getOwner().getName());
        Log.d("winnerIdea ", "voteCount: " + winnerIdea.getVoteCount());
    } catch (Exception e) {
        e.printStackTrace();
        Log.d("winnerIdea ", "winnerIdea is null!!");
    }

    try {
        holder.voteCardNr.setText("  " + (++increment));
        holder.voteCardWinnerIdeaOwner.setText("  " + winnerIdea.getOwner().getName());
        try {
            holder.voteCardWinnerIdeaVotes.setText("  " + winnerIdea.getVoteCount());
        } catch (Exception e) {
            e.printStackTrace();
            holder.voteCardWinnerIdeaVotes.setText("  " + "0");
        }
            holder.voteCardWinnerIdea.setText("  " + winnerIdea.getTitle());
            holder.voteCardDatum.setText("  am " + mDay + "." + mMonth + "." + mYear);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void setClickListener (ClickListener clickListener) {
    this.clickListener = clickListener;
}

@Override
public int getItemCount() {
    return votingList.size();
}

class votingHistoryViewHolder extends HotFixRecyclerView.ViewHolder implements View.OnClickListener{
    TextView voteCardNr;
    TextView voteCardWinnerIdeaOwner;
    TextView voteCardWinnerIdea;
    TextView voteCardWinnerIdeaVotes;
    TextView voteCardDatum;

    public votingHistoryViewHolder(View itemView) {
        super(itemView);

        itemView.setOnClickListener(this);
        VotingHistoryCardLayout layout = (VotingHistoryCardLayout) itemView.findViewById(R.id.voteRecycleCardLayout);

        List<TextView> views = layout.getVotingHistoryCards();

        try {
            voteCardNr = views.get(0);
            voteCardWinnerIdea = views.get(1);
            voteCardWinnerIdeaOwner = views.get(2);
            voteCardWinnerIdeaVotes = views.get(3);
            voteCardDatum = views.get(4);
        }catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onClick(View v) {
        if(clickListener != null) {
            clickListener.itemClicked(v, getAdapterPosition());
        }
    }
}

public interface ClickListener{
    void itemClicked(View view, int position);
}

}

voting_history_row.xml：

   <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/asdasd">

<smoca.ch.kreagen.layouts.VotingHistoryCardLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/voteRecycleCardLayout"
    android:orientation="vertical"

    />

</LinearLayout>

VotingHistoryCardLayout.java：

public class VotingHistoryCardLayout extends LinearLayout{
    private ArrayList<TextView> views;

    // three different constructors to fit any kind of invoke
    public VotingHistoryCardLayout(Context context) {
        super(context);
        init();
    }

    public VotingHistoryCardLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public VotingHistoryCardLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    // Initialize the Layout
    private void init() {
        views = new ArrayList<>();
        LayoutInflater li = LayoutInflater.from(getContext());

        // Dimension: 1x3
        LinearLayout newLayout = new LinearLayout(getContext());
        // set Orientation for each row
        newLayout.setGravity(Gravity.CENTER_HORIZONTAL);
        newLayout.setOrientation(LinearLayout.HORIZONTAL);
        this.addView(newLayout);

        // create new Card
        CardView card1 = (CardView) li.inflate(R.layout.voting_history_cards, newLayout, false);

        // set card color
        card1.setCardBackgroundColor(getResources().getColor(R.color.Green));

        // add Views to newLayout
        newLayout.addView(card1);

        views.add((TextView) findViewById(R.id.voteCardNrContent));     // index 0
        views.add((TextView)card1.findViewById(R.id.voteCardWinnerIdeaContent));    // index 1
        views.add((TextView)card1.findViewById(R.id.voteCardOwnerContent));     // index 2
        views.add((TextView)card1.findViewById(R.id.voteCardVotesContent));     // index 3
        views.add((TextView)card1.findViewById(R.id.voteCardDateContent));      // index 4
    }

public ArrayList<TextView> getVotingHistoryCards() {
    return views;
}

}

voting_history_cards.xml：

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView                xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardCornerRadius="8dp"
android:layout_margin="10dp"> <RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/label_nr"
    android:id="@+id/voteCardNrLabel"/>
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="1"
    android:id="@+id/voteCardNrContent"
    android:layout_alignParentTop="true"
    android:layout_toEndOf="@+id/voteCardNrLabel" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/label_winnerIdea"
    android:id="@+id/voteCardWinnerIdeaLabel"
    android:layout_below="@+id/voteCardNrLabel"
    android:layout_alignStart="@+id/voteCardNrLabel" />
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="KreaGen"
    android:id="@+id/voteCardWinnerIdeaContent"
    android:layout_above="@+id/voteCardOwnerLabel"
    android:layout_toEndOf="@+id/voteCardWinnerIdeaLabel" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/label_winner"
    android:id="@+id/voteCardOwnerLabel"
    android:layout_below="@+id/voteCardWinnerIdeaLabel"
    android:layout_alignParentStart="true" />
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Joris"
    android:id="@+id/voteCardOwnerContent"
    android:layout_alignBaseline="@+id/voteCardOwnerLabel"
    android:layout_alignBottom="@+id/voteCardOwnerLabel"
    android:layout_toEndOf="@+id/voteCardOwnerLabel" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/label_Votes"
    android:id="@+id/voteCardVotesLabel"
    android:layout_below="@+id/voteCardOwnerLabel"
    android:layout_alignParentStart="true" />
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="0"
    android:id="@+id/voteCardVotesContent"
    android:layout_alignBaseline="@+id/voteCardVotesLabel"
    android:layout_alignBottom="@+id/voteCardVotesLabel"
    android:layout_toEndOf="@+id/voteCardVotesLabel" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/label_Date"
    android:id="@+id/voteCardDateLabel"
    android:layout_below="@+id/voteCardVotesLabel"
    android:layout_alignStart="@+id/voteCardVotesLabel" />
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="20.02.1997"
    android:id="@+id/voteCardDateContent"
    android:layout_below="@+id/voteCardVotesContent"
    android:layout_toEndOf="@+id/voteCardDateLabel" />
</RelativeLayout>
</android.support.v7.widget.CardView>

Answer 1

的确，你的第一个空排有点奇怪。我可以看到的唯一原因是，或者您的请求要么配置了RealmList类，以便返回空的第一行。仔细检查一下。

否则，要删除RecyclerView中的第一行，它非常简单：删除在适配器中分配数组之前的第一项。

更改你的getVotingList函数：

private RealmList<Voting> getVotingList() { RealmList<Voting> votingList = new RealmList<>(); if(votingList.size() > 0){ votingList.remove(0); } votingList.addAll(realm.where(Voting.class).equalTo(Constants.TAG_STATUS, false).findAllSorted(Constants.TAG_TIMESTAMP)); return votingList; }

删除recyclerView的第一行

1 个答案: