4
我有一個回收器視圖，直到我滾動時才顯示任何元素。一旦我滾動它，任何已完全離屏的項目都會顯示，但任何未完成的項目都不會顯示。RecycerView直到滾動後才顯示
片段類：
public class ImageAndNavHeaderFragment extends Fragment {
private NetworkImageView mBackgroundImage;
private RecyclerView mScrollingTextNavBar;
private ScrollingTextNavBarAdapter mScrollingBarAdapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.image_and_nav_header, container, false);
mBackgroundImage = (NetworkImageView) view.findViewById(R.id.bgImage);
mBackgroundImage.setImageUrl("http://crookedcreekguides.com/wp-content/uploads/2016/01/dinner-03.jpg", VolleySingleton.getInstance(getContext()).getImageLoader());
mScrollingTextNavBar = (RecyclerView) view.findViewById(R.id.scrollTextNavBar);
LinearLayoutManager layoutManager = new LinearLayoutManager(getContext());
layoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
mScrollingTextNavBar.setLayoutManager(layoutManager);
ArrayList<String> list = new ArrayList<>();
for(int i=0; i< 20; i++) {
list.add("Test " + i);
}
mScrollingBarAdapter = new ScrollingTextNavBarAdapter(getContext(), list);
mScrollingTextNavBar.setAdapter(mScrollingBarAdapter);
view.invalidate();
return view;
}
}
適配器
public class ScrollingTextNavBarAdapter extends RecyclerView.Adapter<ScrollingTextNavBarAdapter.ViewHolder>{
private List<String> mStrings;
private int mSelectedIndex = 0;
private int mSelectedColor;
private int mDefaultColor;
private ItemClickedListener mListener;
private Drawable mSelectedDrawable;
private class PositionClickListener implements View.OnClickListener{
private int mPosition;
public PositionClickListener() {
}
@Override
public void onClick(View view){
if(mPosition != mSelectedIndex) {
mSelectedIndex = mPosition;
notifyDataSetChanged();
if(mListener != null) {
mListener.onClick(mPosition);
}
}
}
public void setPosition(int position) {
mPosition = position;
}
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView textView;
public PositionClickListener listener;
public ViewHolder(TextView view) {
super(view);
textView = view;
listener = new PositionClickListener();
}
}
public ScrollingTextNavBarAdapter(Context context) {
mStrings = new ArrayList<>();
init(context);
}
public ScrollingTextNavBarAdapter(Context context, List<String> items) {
mStrings = items;
init(context);
}
@SuppressWarnings("deprecation")
private void init(Context context){
mSelectedColor = context.getResources().getColor(R.color.scrolling_text_nav_bar_text_selected_color);
mDefaultColor = context.getResources().getColor(R.color.scrolling_text_nav_bar_text_default_color);
mSelectedDrawable = context.getResources().getDrawable(R.drawable.scrolling_text_nav_bar_seected_drawable);
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
TextView view = (TextView)LayoutInflater.from(parent.getContext()).inflate(R.layout.scrolling_text_nav_bar_item, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
holder.textView.setText(mStrings.get(position));
holder.textView.setTextColor(position == mSelectedIndex ? mSelectedColor : mDefaultColor);
holder.listener.setPosition(position);
holder.textView.setOnClickListener(holder.listener);
holder.textView.setBackground(position == mSelectedIndex? mSelectedDrawable : null);
}
@Override
public int getItemCount() {
return mStrings.size();
}
public void addString(String text) {
mStrings.add(text);
notifyDataSetChanged();
}
public void setItemClickedListener(ItemClickedListener listener) {
mListener = listener;
}
}
片段的xml：
<?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="wrap_content"
>
<com.android.volley.toolbox.NetworkImageView
android:id="@+id/bgImage"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
<android.support.v7.widget.RecyclerView
android:id="@+id/scrollTextNavBar"
android:layout_width="match_parent"
android:layout_height="40dp"
android:layout_alignBottom="@id/bgImage"
/>
</RelativeLayout>
爲了進一步amusement-後我滾動一個項目到視圖和它的出現，點擊一項（它調用notifyDataSetChanged）將顯示所有這些。但是如果不進行滾動（即使有延遲），也無法解決問題。
添加日誌記錄，以解決我的'onCreateViewHolder（）'和'onBindViewHolder（）'，看看你是否滾動或在此之前他們獲取調用。另外，您是否嘗試過層次結構視圖以查看預滾動的內容是否存在但隱藏或缺失？ – CommonsWare
函數被調用前20個位置中的前11個。 –
至於HierarchyViewer - 採取屏幕截圖的行爲會使所有內容都顯示出來。 –