Develop Reference

Getting a RecyclerView to reload items

I am currently working on an app, that finds all MP3s on a users phone and then puts them into a list. This works very fine and is very quick, even with many songs. Now I populate a new list with an object for each item of the list to then display it inside my recyclerview. The problem is, that I have 700+ songs on my phone and this blocks the UI thread quite some time.
Now, I want to use the recyclerview to not load all items from the list into the objects all at once but rather only when they are about to be displayed - but I have NO clue over how to do this. Right now, all objects are build and then displayed in a very long scrollview from the recyclerview after the UI thread has been blocked for a good 30 seconds. Can please anyone help me? Here is my code:
namespace Media_Player
{
[Activity(Label = "Media_Player", MainLauncher = true)]
public class MainActivity : Activity
{
static public MediaPlayer mediaPlayer;
List<MP3object> mp3;
MediaMetadataRetriever reader;
public static Button btn_StartOrPause, btn_Stop;
public static TextView txt_CurrentSong;
public static bool stopIsActive = false, firstStart = true;
public static Android.Net.Uri CurrentActiveSongUri;
RecyclerView mRecyclerView;
RecyclerView.LayoutManager mLayoutManager;
PhotoAlbumAdapter mAdapter;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.test);
reader = new MediaMetadataRetriever();
PopulateMP3List(ReturnPlayableMp3(true));
mediaPlayer = new MediaPlayer();
InitRecView();
}
private void InitRecView()
{
// Instantiate the adapter and pass in its data source:
mAdapter = new PhotoAlbumAdapter(mp3);
// Get our RecyclerView layout:
mRecyclerView = FindViewById<RecyclerView>(Resource.Id.recyclerView);
// Plug the adapter into the RecyclerView:
mRecyclerView.SetAdapter(mAdapter);
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.SetLayoutManager(mLayoutManager);
}
private void PopulateMP3List(List<string> content)
{
mp3 = new List<MP3object>();
foreach (string obj in content)
{
WriteMetaDataToFileList(obj);
}
}
void WriteMetaDataToFileList(string obj)
{
reader.SetDataSource(obj);
//Write Mp3 as object to global list
MP3object ob = new MP3object();
{
if(reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyTitle) != "" && reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyTitle) != null)
{
ob.SongName = reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyTitle);
}
else
{
ob.SongName = Resources.GetString(Resource.String.Unknown);
}
if (reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyArtist) != "" && reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyArtist) != null)
{
ob.ArtistName = reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyArtist);
}
else
{
ob.ArtistName = Resources.GetString(Resource.String.Unknown);
}
if (reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyAlbum) != "" && reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyAlbum) != null)
{
ob.AlbumName = reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyAlbum);
}
else
{
ob.AlbumName = Resources.GetString(Resource.String.Unknown);
}
if (reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear) != "" && reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear) != null)
{
ob.Year = reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear);
}
else
{
ob.Year = Resources.GetString(Resource.String.Unknown);
}
if (reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear) != "" && reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear) != null)
{
ob.Year = reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyYear);
}
else
{
ob.Year = Resources.GetString(Resource.String.Unknown);
}
ob.Mp3Uri = obj; // can never be unknown!
ob.DurationInSec = int.Parse(reader.ExtractMetadata(MediaMetadataRetriever.MetadataKeyDuration)) / 1000; // can never be unknown, div by 1000 to get sec not millis
}
mp3.Add(ob);
}
public List<string> ReturnPlayableMp3(bool sdCard)
{
List<string> res = new List<string>();
string phyle;
string path1 = null;
if(sdCard) // get mp3 from SD card
{
string baseFolderPath = "";
try
{
bool getSDPath = true;
Context context = Application.Context;
Java.IO.File[] dirs = context.GetExternalFilesDirs(null);
foreach (Java.IO.File folder in dirs)
{
bool IsRemovable = Android.OS.Environment.InvokeIsExternalStorageRemovable(folder);
bool IsEmulated = Android.OS.Environment.InvokeIsExternalStorageEmulated(folder);
if (getSDPath ? IsRemovable && !IsEmulated : !IsRemovable && IsEmulated)
baseFolderPath = folder.Path;
}
}
catch (Exception ex)
{
Console.WriteLine("GetBaseFolderPath caused the following exception: {0}", ex);
}
string xy = baseFolderPath.Remove(18); // This is result after this, but this hard coded solution could be a problem on different phones.: "/storage/05B6-2226/Android/data/Media_Player.Media_Player/files"
path1 = xy;
// path to SD card and MUSIC "/storage/05B6-2226/"
}
else // get Mp3 from internal storage
{
path1 = Android.OS.Environment.ExternalStorageDirectory.ToString();
}
var mp3Files = Directory.EnumerateFiles(path1, "*.mp3", SearchOption.AllDirectories);
foreach (string currentFile in mp3Files)
{
phyle = currentFile;
res.Add(phyle);
}
return res;
}
}
public class PhotoViewHolder : RecyclerView.ViewHolder
{
public ImageView Image { get; private set; }
public TextView Caption { get; private set; }
public PhotoViewHolder(View itemView) : base(itemView)
{
// Locate and cache view references:
Image = itemView.FindViewById<ImageView>(Resource.Id.imageView);
Caption = itemView.FindViewById<TextView>(Resource.Id.textView);
}
}
public class PhotoAlbumAdapter : RecyclerView.Adapter
{
public List<MP3object> mp3;
public PhotoAlbumAdapter(List<MP3object> mp3)
{
this.mp3 = mp3;
}
public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
{
View itemView = LayoutInflater.From(parent.Context).
Inflate(Resource.Layout.lay, parent, false);
PhotoViewHolder vh = new PhotoViewHolder(itemView);
return vh;
}
public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int position)
{
PhotoViewHolder vh = holder as PhotoViewHolder;
vh.Caption.Text = mp3[position].SongName;
}
public override int ItemCount
{
get { return mp3.Count(); }
}
}
}
So getting the list of strings with the locations of the Mp3 works very quickly, but then "WriteMetaDataToFileList(obj)" kicks in, comming from "PopulateMP3List(List content)" and this is what takes so long. What I think I need is for the recyclerview to only build the first 20 objects, and when the user starts scrolling, builds the next 20 objects and attaches them to list for them to also be scrolled. Please help me out here :)

Here is an abstract class:
public abstract class PaginationScrollListener extends RecyclerView.OnScrollListener {
private LinearLayoutManager linearLayoutManager;
protected PaginationScrollListener(LinearLayoutManager linearLayoutManager) {
this.linearLayoutManager = linearLayoutManager;
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int visibleItemCount = linearLayoutManager.getChildCount();
int totalItemCount = linearLayoutManager.getItemCount();
int firstVisibleItemPosition = linearLayoutManager.findFirstVisibleItemPosition();
if (!isLoading() && !isLastPage()) {
if ((visibleItemCount + firstVisibleItemPosition) >= totalItemCount && firstVisibleItemPosition >= 0) {
loadMoreItems();
}
}
}
protected abstract void loadMoreItems();
public abstract boolean isLastPage();
public abstract boolean isLoading();
}
and In your adapter you must follow this pattern:
public class ConsultancyAdapter extends RecyclerView.Adapter<ConsultancyAdapter.ConsultancyVH> {
private static final int ITEM = 0;
private static final int LOADING = 1;
private boolean isLoadingAdded = false;
public ConsultancyAdapter(List<Consultancy> consultancies, ConsultancyAdapterListener listener) {
}
#NonNull
#Override
public ConsultancyVH onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
RecyclerView.ViewHolder viewHolder = null;
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
switch (viewType) {
case ITEM:
viewHolder = getViewHolder(parent, layoutInflater);
break;
case LOADING:
View v2 = layoutInflater.inflate(R.layout.item_progress, parent, false);
viewHolder = new ConsultancyVH(v2);
break;
}
return (ConsultancyVH) viewHolder;
}
#NonNull
private RecyclerView.ViewHolder getViewHolder(ViewGroup parent, LayoutInflater inflater) {
RecyclerView.ViewHolder viewHolder;
View v1 = inflater.inflate(R.layout.item_consultancy, parent, false);
viewHolder = new ConsultancyVH(v1);
return viewHolder;
}
#Override
public void onBindViewHolder(#NonNull ConsultancyVH holder, int position) {
Consultancy consultancy = consultancies.get(position);
switch (getItemViewType(position)) {
case ITEM:
ConsultancyVH mySingeCounseller = holder;
holder.title.setText(consultancy.getTitle()); // set cardTitle
holder.fieldArea.setText(consultancy.getField_filedoctorskills());
break;
case LOADING:
break;
}
}
#Override
public int getItemCount() {
return consultancies.size();
}
#Override
public int getItemViewType(int position) {
return (position == consultancies.size() - 1 && isLoadingAdded) ? LOADING : ITEM;
}
public void add(Consultancy mc) {
consultancies.add(mc);
notifyItemInserted(consultancies.size() - 1);
}
public void addAll(List<Consultancy> mcList) {
for (Consultancy mc : mcList) {
add(mc);
}
}
public void remove(Consultancy city) {
int position = consultancies.indexOf(city);
if (position > -1) {
consultancies.remove(position);
notifyItemRemoved(position);
}
}
public Consultancy getItem(int position) {
return consultancies.get(position);
}
public void clear() {
isLoadingAdded = false;
while (getItemCount() > 0) {
remove(getItem(0));
}
}
public boolean isEmpty() {
return getItemCount() == 0;
}
public void addLoadingFooter() {
isLoadingAdded = true;
add(new Consultancy());
}
public void removeLoadingFooter() {
isLoadingAdded = false;
int position = consultancies.size() - 1;
Consultancy item = getItem(position);
if (item != null) {
consultancies.remove(position);
notifyItemRemoved(position);
}
}
public interface ConsultancyAdapterListener {
void onCaseClicked(int position, String nid, String fieldArea, String title);
}
protected class ConsultancyVH extends RecyclerView.ViewHolder {
private TextView title, fieldArea;
private CircleImageView iconProfile;
private MaterialRippleLayout caseButtonRipple;
public ConsultancyVH(View itemView) {
super(itemView);
caseButtonRipple = itemView.findViewById(R.id.case_button_ripple);
this.title = itemView.findViewById(R.id.docName);
this.fieldArea = itemView.findViewById(R.id.fieldArea);
this.iconProfile = itemView.findViewById(R.id.icon_profile);
}
}
}
and in your activity:
private void setScrollListener() {
recyclerView.addOnScrollListener(new PaginationScrollListener(linearLayoutManager) {
#Override
protected void loadMoreItems() {
isLoading = true;
currentPage += 1;
loadNextPage();
}
#Override
public boolean isLastPage() {
return isLastPage;
}
#Override
public boolean isLoading() {
return isLoading;
}
});
loadFirstPage();
}
and in my loadFirstPage i talk to a API and you need some your code:
private void loadFirstPage() {
CallData().enqueue(new DefaultRetrofitCallback<List<Consultancy>>() {
#Override
protected void onFailure(Throwable t) {
super.onFailure(t);
}
#Override
protected void onSuccess(List<Consultancy> response) {
swipeRefreshLayout.setRefreshing(false);
dataList = response;
adapter.addAll(dataList);
recyclerView.setAdapter(adapter);
if (!checkLast(response)) adapter.addLoadingFooter();
else isLastPage = true;
}
#Override
protected void onOtherStatus(Response<List<Consultancy>> response) {
super.onOtherStatus(response);
}
#Override
protected void always() {
super.always();
}
});
}
and loadNextPage:
private void loadNextPage() {
CallData().enqueue(new DefaultRetrofitCallback<List<Consultancy>>() {
#Override
protected void onFailure(Throwable t) {
super.onFailure(t);
}
#Override
protected void onSuccess(List<Consultancy> response) {
swipeRefreshLayout.setRefreshing(false);
adapter.removeLoadingFooter();
isLoading = false;
swipeRefreshLayout.setRefreshing(false);
adapter.addAll(response);
if (!checkLast(response)) adapter.addLoadingFooter();
else isLastPage = true;
}
#Override
protected void onOtherStatus(Response<List<Consultancy>> response) {
super.onOtherStatus(response);
}
#Override
protected void always() {
super.always();
}
});
}

While searching using EditText, the items in Recyclerview is duplicating, if i am searching fast

In my project, there is need of searching data from server using keyword. After search, i am displaying results using RecyclerView . While searching fast, the data in RecyclerView is duplicating. If searching slowly, it's working fine. Any suggestions are appreciated. Thank you.
The below code for making server call:
private void callSearchUserApi(final String searchText, int currentPage, boolean clearData) {
isApiCallInProcess = true;
String URL = "userinfo/api/v1/user-search/" + "?page=" + currentPage;
if (!Connectivity.isConnected(activity)) {
Common.snackBarNoConnection(activity, activity.getString(R.string.no_conection));
//setOnProgressbarVisibility(View.GONE);
return;
}
if (clearData) {
globalSearchUsersModelList.clear();
//BS globalSearchUserResultsAdapter.notifyDataSetChanged();
}
ApiInterface apiCall = ApiClient.getApiService(activity);
final Call<SearchUsersModel> globalUserSearchApiCall = apiCall.searchUser(
URL,
searchText);
globalUserSearchApiCall.enqueue(new Callback<SearchUsersModel>() {
#Override
public void onResponse(Call<SearchUsersModel> call, Response<SearchUsersModel> response) {
if (response.isSuccessful() && response.body().getStatus().equalsIgnoreCase(Common.SUCCESS_RESPONSE)) {
//BS globalSearchUsersModelList.addAll(response.body().getData().getData());
for (int i = 0; i < response.body().getData().getData().size(); i++) {
SearchUsersModel.DataBeanX.DataBean dataBean = new SearchUsersModel.DataBeanX.DataBean();
dataBean.setDesignation(response.body().getData().getData().get(i).getDesignation());
dataBean.setFull_name(response.body().getData().getData().get(i).getFull_name());
dataBean.setGender(response.body().getData().getData().get(i).getGender());
dataBean.setId(response.body().getData().getData().get(i).getId());
dataBean.setPlace(response.body().getData().getData().get(i).getPlace());
dataBean.setProfile_pic(response.body().getData().getData().get(i).getProfile_pic());
globalSearchUsersModelList.add(dataBean);
/*BS if (!globalSearchUsersModelList.contains(response.body().getData().getData().get(i)))
globalSearchUsersModelList.add(response.body().getData().getData().get(i));*/
}
CURRENT_PAGE = response.body().getData().getPage();
isLoading = false;
if (response.body().getData().isNext() == false)
isLastPage = true;
else
isLastPage = false;
if (globalSearchUsersModelList.size() == 0) {
rv_GlobalsearchList.setVisibility(View.GONE);
rl_placeholderGSPeople.setVisibility(View.VISIBLE);
tv_placeholderGSPeople.setText(activity.getString(R.string.no_search_found) + " " + searchText);
} else {
rv_GlobalsearchList.setVisibility(View.VISIBLE);
rl_placeholderGSPeople.setVisibility(View.GONE);
}
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
globalSearchUserResultsAdapter.notifyDataSetChanged();
}
});
}
if (searchTextsList.size() > 0) {
String sText = searchTextsList.get(0);
searchTextsList.remove(0);
callSearchUserApi(sText, FIRST_PAGE, true);
} else
isApiCallInProcess = false;
}
#Override
public void onFailure(Call<SearchUsersModel> call, Throwable t) {
isApiCallInProcess = false;
}
});
}
This is my Adapter.
public class GlobalSearchUserResultsAdapter extends RecyclerView.Adapter<GlobalSearchUserResultsAdapter.SearchViewHolder> {
private Context context;
private List<SearchUsersModel.DataBeanX.DataBean> searchUserList;
public GlobalSearchUserResultsAdapter(Context context, List<SearchUsersModel.DataBeanX.DataBean> searchUserList){
this.context = context;
this.searchUserList = searchUserList;
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public int getItemViewType(int position) {
return position;
}
#Override
public SearchViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
Log.v("Search", "Adapter Activity : "+context);
View view = LayoutInflater.from(context).inflate(R.layout.global_search_row, parent, false);
return new GlobalSearchUserResultsAdapter.SearchViewHolder(view);
}
#Override
public void onBindViewHolder(GlobalSearchUserResultsAdapter.SearchViewHolder holder, int position) {
if ( searchUserList.get(position).getGender().equals("M")) {
holder.iv_userImage.setBackgroundResource(R.drawable.white_border_with_circle_appblue);
Common.setGlideImage((GlobalSearchActivity)context,
holder.iv_userImage,
/*searchUsersModel*/searchUserList.get(position).getProfile_pic(),
R.drawable.male,
true);
} else if (searchUserList.get(position).getGender().equals("F")) {
holder.iv_userImage.setBackgroundResource(R.drawable.white_border_with_circle_pink);
Common.setGlideImage((GlobalSearchActivity)context,
holder.iv_userImage,
searchUserList.get(position).getProfile_pic(),
R.drawable.female,
true);
} else {
Common.setGlideImage((GlobalSearchActivity)context,
holder.iv_userImage,
searchUserList.get(position).getProfile_pic(),
R.drawable.deafult_profilepic,
true);
}
holder.tv_userName.setText(searchUserList.get(position).getFull_name());
holder.tv_userName.setTypeface(Common
.getFontTypeface(context, GlobalConstants.FONT_AVENIR_MEDIUM));
holder.tv_place.setText(searchUserList.get(position).getPlace());
holder.tv_place.setTypeface(Common
.getFontTypeface(context, GlobalConstants.FONT_AVENIR_MEDIUM));
holder.designation.setText(searchUserList.get(position).getDesignation());
}
#Override
public int getItemCount() {
return searchUserList.size();
}
public class SearchViewHolder extends RecyclerView.ViewHolder{
private ImageView iv_userImage;
private TextView tv_userName;
private TextView tv_place;
private TextView designation;
public SearchViewHolder(View itemView) {
super(itemView);
this.iv_userImage = (ImageView) itemView.findViewById(R.id.imageSearch);
this.tv_userName = (TextView) itemView.findViewById(R.id.nameSearch);
tv_userName.setTypeface(Common.getFontTypeface(context,
GlobalConstants.FONT_AVENIR_MEDIUM));
this.designation = (TextView) itemView.findViewById(R.id.designation);
designation.setTypeface(Common.getFontTypeface(context,
GlobalConstants.FONT_AVENIR_MEDIUM));
this.tv_place = (TextView) itemView.findViewById(R.id.placeSearch);
tv_place.setTypeface(Common.getFontTypeface(context,
GlobalConstants.FONT_AVENIR_LIGHT));
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
context.startActivity(new Intent(context, ProfileActivity.class)//ThirdParty
.putExtra(GlobalConstants.KEY_THIRD_PARTY_ID, searchUserList.get(getAdapterPosition()).getId()));
}
});
}
}
}

You just had to clear the globalSearchUsersModelList list just before for loop, because API call is asynchronous.
globalSearchUsersModelList.clear();// Important one
for (int i = 0; i < response.body().getData().getData().size(); i++) {
// do your stuff
}

I think the issue come from your getItemId implementation. The way you implement it, the recycler view will identify an item according to its position in the list.
If you change this and use unique identification for instance searchUserList.get(position).id (if your User object has an unique ID) the problem should be fixed
You can also add in your activity adapter.setHasStableIds(true)

viewholder does not maintain its state when scrolled off screen

I have a music player app where when an item is clicked it changes its state to 'play' state where it gets expanded to show a seek bar and other changes also take place and vice versa.
The problem is whenever I scroll up or down, the view holder swaps its current state(playing, paused visibility in this case) with some other random view in the list. It is also worth mentioning that this is consistent throughout the list so after every certain number of view holders, the state is the same as the one that was clicked (so if view at position 0 is in play visibility state after every 10 views a view is in the same state, note however the song still plays for the right one).
Here is the Adapter code (extends from a base adapter and the methods for play/pause visibility can be found here which are used in the song fragment code below):
public class AllSongsAdapter extends BaseSongAdapter<AllSongsAdapter.AllSongsItemHolder> {
private ArrayList<Song> songList;
public AllSongsAdapter(){
super(null);
}
//OnCreateViewHolder was called for every view;
//FIX: return 0 for same type of views.
#Override
public int getItemViewType(int position) {
return 0;
}
//cursor moves to the appropriate position in the list so we just have to update our views
#Override
public void onBindViewHolder(AllSongsItemHolder holder, Cursor cursor) {
if(cursor!=null) {
int i = cursor.getPosition();
Log.d("on Bind", "i:" + i);
Song songItem = songList.get(i);
holder.songItemName.setText(songItem.title);
holder.songItemArtistName.setText(songItem.artistName);
holder.songItemAlbumName.setText(songItem.albumName);
}
}
#Override
public void swapCursor(Cursor newCursor) {
super.swapCursor(newCursor);
songList = SongsLoader.getSongsForCursor(newCursor);
}
#Override
public AllSongsItemHolder onCreateViewHolder(ViewGroup parent, int viewType) {
Log.d("CREATE VIEW HOLDER", "holder" );
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.songs_item_list, parent, false);
return new AllSongsItemHolder(v);
}
private Uri getAlbumArtUri(long albumId) {
return ContentUris.withAppendedId(Uri.parse("content://media/external/audio/albumart"), albumId);
}
public void setPlayVisibility(View child, RecyclerView rv) {
//View v = rv.getChildAt(rv.getChildAdapterPosition(child));
AllSongsItemHolder holder = (AllSongsItemHolder) rv.getChildViewHolder(child);
// if(getItemId(position) == rv.getChildItemId(v)){}
holder.seekBar.setVisibility(View.VISIBLE);
holder.songItemTimer.setVisibility(View.VISIBLE);
holder.songItemImage.setScaleType(ImageView.ScaleType.CENTER);
holder.songItemImage.setBackgroundColor(Color.parseColor("#303F9F"));
}
public void setPauseVisibility(View child, RecyclerView rv) {
//View v = rv.getChildAt(rv.getChildAdapterPosition(child));
AllSongsItemHolder holder = (AllSongsItemHolder) rv.getChildViewHolder(child);
//if(getItemId(position) == rv.getChildItemId(v)){}
holder.seekBar.setVisibility(View.GONE);
holder.songItemTimer.setVisibility(View.GONE);
holder.songItemImage.setScaleType(ImageView.ScaleType.FIT_XY);
holder.songItemImage.setBackgroundColor(0);
}
static class AllSongsItemHolder extends RecyclerView.ViewHolder {
private ImageView songItemImage, songItemOptionDropDown;
private TextView songItemName, songItemAlbumName, songItemArtistName;
private View separator;
private SeekBar seekBar;
private ImageView nowPlayingIcon;
private TextView songItemTimer;
public AllSongsItemHolder(View v) {
super(v);
songItemImage = v.findViewById(R.id.songItemImage);
songItemOptionDropDown = v.findViewById(R.id.songItemOptionDropDown);
songItemAlbumName = v.findViewById(R.id.songItemAlbumName);
songItemArtistName = v.findViewById(R.id.songItemArtistName);
songItemName = v.findViewById(R.id.songItemName);
separator = v.findViewById(R.id.separator);
seekBar = v.findViewById(R.id.seekbar);
songItemTimer = v.findViewById(R.id.songItemTimer);
// nowPlayingIcon = v.findViewById(R.id.nowPlayingIcon);
}
}
}
I noticed that when getItemViewType returns position this problem does not occur because recycler view holds an instance for every item in the list. But clearly this is not an adequate solution because it slows down the scrolling when first loaded as it has to create every view. Could be something to do with this?
BaseAdapter code:
public abstract class BaseSongAdapter<VH extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<VH> {
protected Cursor mCursor;
protected int mRowIDColumn;
protected boolean mDataValid;
public BaseSongAdapter(Cursor c) {
init(c);
}
public BaseSongAdapter() {}
void init(Cursor c) {
boolean cursorPresent = c != null;
mCursor = c;
mDataValid = cursorPresent;
mRowIDColumn = cursorPresent ? c.getColumnIndexOrThrow("_id") : -1;
setHasStableIds(true);
if(mDataValid && mCursor!=null) {
Log.d("VALID", "CURSOR");
}
}
#Override
public void onBindViewHolder(VH holder, int position) {
//Log.d("ON BIND","CALLED");
if (!mDataValid) {
throw new IllegalStateException("Cannot bind viewholder when cursor is in invalid state.");
}
if (!mCursor.moveToPosition(position)) {
throw new IllegalStateException("Could not move cursor to position " + position + " when trying to bind viewholder");
}
onBindViewHolder(holder, mCursor);
}
public abstract void onBindViewHolder(VH holder, Cursor cursor);
#Override
public int getItemViewType(int position) {
return position;
}
#Override
public int getItemCount() {
if (mDataValid) {
return mCursor.getCount();
} else {
return 0;
}
}
#Override
public long getItemId(int position) {
if (!mDataValid) {
throw new IllegalStateException("Cannot lookup item id when cursor is in invalid state.");
}
if (!mCursor.moveToPosition(position)) {
throw new IllegalStateException("Could not move cursor to position " + position + " when trying to get an item id");
}
return mCursor.getLong(mRowIDColumn);
}
public void swapCursor(Cursor newCursor) {
if (newCursor == mCursor) {
return;
}
//Log.d("TAG", "swapCursor");
//Cursor oldCursor = mCursor;
if (newCursor != null) {
mCursor = newCursor;
mRowIDColumn = newCursor.getColumnIndexOrThrow("_id");
mDataValid = true;
// notify the observers about the new cursor
notifyDataSetChanged();
} else {
mCursor = null;
mRowIDColumn = -1;
mDataValid = false;
// notify the observers about the lack of a data set
notifyItemRangeRemoved(0, getItemCount());
}
//return oldCursor;
}
}
Song Fragment code where clicks are handled(in onActivityCreated):
public class AllSongsFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> {
private final int LOADER_ID_ALLSONGS = 0;
private Context ctx;
private AllSongsAdapter mAdapter;
private MediaPlayerHolder mediaPlayerHolder;
//on click play,pause variables
private boolean playingCLicked = false;
private boolean firstTime = true;
private String playbackState;
private View lastChildView;
private long currentSongId;
private long newID;
private long nextID; //id for next song
private int lastTrackPosition; //for auto next track
private RecyclerView rv;
public AllSongsFragment() {
super();
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
ctx = context;
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getLoaderManager().initLoader(LOADER_ID_ALLSONGS, null, this);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.all_songs_fragment, container, false);
return view;
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
rv = (RecyclerView) getActivity().findViewById(R.id.fragmentList);
mediaPlayerHolder = new MediaPlayerHolder(getActivity());
mediaPlayerHolder.setPlaybackInfoListener(new PlaybackListener());
rv.addOnItemTouchListener(new RecyclerTouchListener(getActivity(), rv, new ClickListener() {
#Override
public void click(View view, final int position) {
Toast.makeText(getActivity(), "onClick " + position, Toast.LENGTH_SHORT).show();
newID = mAdapter.getItemId(position);
if (playingCLicked) {
if (mediaPlayerHolder.isPlaying()) {
if (currentSongId == newID) {
mAdapter.setPauseVisibility(view, rv);
lastChildView = view;
}
//PAUSE IT
mediaPlayerHolder.pause();
Log.d("playingclicked", "true" + "state" + playbackState);
//when a different song is clicked while current song is playing
if (playbackState.equalsIgnoreCase("paused") && newID != currentSongId) {
currentSongId = newID;
mAdapter.setPauseVisibility(lastChildView, rv);
mAdapter.setPlayVisibility(view, rv);
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
mediaPlayerHolder.play();
lastTrackPosition = position;
lastChildView = view;
Log.d("else 1 positions", "currentsongID" + currentSongId + "lasttrack" + lastTrackPosition);
}
playingCLicked = !playingCLicked;
} else { //media is not playing
Log.d("else 1", "play");
if (firstTime) {
Log.d("different", "no");
currentSongId = newID;
lastTrackPosition = position;
lastChildView = view;
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
Log.d("SelectedTrack", "" + mediaPlayerHolder.getMediaPlayer().getSelectedTrack(MEDIA_TRACK_TYPE_AUDIO));
firstTime = false;
}
if (newID != currentSongId) {
Log.d("different", "yes");
//mediaPlayerHolder.stop();
currentSongId = newID;
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
firstTime = true;
}
if (currentSongId == newID)
mAdapter.setPlayVisibility(view, rv);
//PLAY IT
mediaPlayerHolder.play();
playingCLicked = !playingCLicked;
}
} else //----------playingclicked = false, first called--------------
{
if (!mediaPlayerHolder.isPlaying()) {
lastChildView = view;
mAdapter.setPlayVisibility(view, rv);
if (firstTime) {
Log.d("different", "no, first time");
currentSongId = newID;
lastTrackPosition = position;
lastChildView = view;
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
Log.d("SelectedTrack", "" + mediaPlayerHolder.getMediaPlayer().getSelectedTrack(MEDIA_TRACK_TYPE_AUDIO));
firstTime = false;
}
Log.d("playbackState", playbackState + "currentId " + currentSongId);
//called when current song is paused and after playingClicked = true following is called if songId is different
if (newID != currentSongId) {
Log.d("different", "yes");
currentSongId = newID;
mediaPlayerHolder.stop();
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
}
//PLAY IT
mediaPlayerHolder.play();
playingCLicked = !playingCLicked;
} else { //media is playing
Log.d("else 2", "pause");
if (newID == currentSongId) {
lastChildView = view;
lastTrackPosition = position;
mAdapter.setPauseVisibility(view, rv);
}
//PAUSE IT
mediaPlayerHolder.pause();
firstTime = false;
//when a different song is clicked while current song is playing
if (playbackState.equalsIgnoreCase("paused") && newID != currentSongId) {
currentSongId = newID;
mAdapter.setPauseVisibility(lastChildView, rv);
mAdapter.setPlayVisibility(view, rv);
mediaPlayerHolder.reset();
mediaPlayerHolder.loadMedia(currentSongId);
mediaPlayerHolder.play();
lastTrackPosition = position;
lastChildView = view;
Log.d("else 2 positions", "currentsongID" + currentSongId + "lasttrack" + lastTrackPosition);
}
playingCLicked = !playingCLicked;
}
}
}
#Override
public void onLongClick(View view, int position) {
Toast.makeText(getActivity(),"onLongClick " + position,Toast.LENGTH_SHORT).show();
}
}));
mAdapter = new AllSongsAdapter();
rv.setAdapter(mAdapter);
LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
rv.setLayoutManager(layoutManager);
//------------Temporary divider-----------------
RecyclerView.ItemDecoration itemDecoration = new DividerItemDecoration(getActivity(), layoutManager.getOrientation());
rv.addItemDecoration(itemDecoration);
}
#Override
public Loader onCreateLoader(int id, Bundle args) {
Log.d("CREATE LOADER", "SUCCESS");
Uri musicUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
final String[] PROJECTION = {"_id", "title", "artist", "album", "duration", "track", "artist_id", "album_id"};
return new CursorLoader(ctx,
musicUri,
PROJECTION,
null,
null,
MediaStore.Audio.Media.DEFAULT_SORT_ORDER );
}
#Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
mAdapter.swapCursor(data);
Log.d("LOAD FINISHED", "SUCCESS");
}
#Override
public void onLoaderReset(Loader loader) {
Log.d("LOADER RESET", "CALLED");
mAdapter.swapCursor(null);
}
class PlaybackListener extends PlaybackStateListener{
#Override
void onDurationChanged(int duration) {
super.onDurationChanged(duration);
}
#Override
void onPositionChanged(int position) {
super.onPositionChanged(position);
}
#Override
void onStateChanged(int state) {
playbackState = PlaybackListener.convertStateToString(state);
}
#Override
void onPlaybackCompleted() {
//super.onPlaybackCompleted();
//pause visibility after completed
mAdapter.setPauseVisibility(lastChildView, rv);
}
#Override
void onLogUpdated(String formattedMessage) {
super.onLogUpdated(formattedMessage);
}
}
//---------------RECYCLER VIEW TOUCH EVENTS LISTENER CLASS------------------------
class RecyclerTouchListener implements RecyclerView.OnItemTouchListener {
private GestureDetector gestureDetector;
private ClickListener mListener;
public RecyclerTouchListener(Context ctx, final RecyclerView recyclerView, ClickListener clickListener){
mListener = clickListener;
gestureDetector = new GestureDetector(ctx, new GestureDetector.OnGestureListener() {
#Override
public boolean onDown(MotionEvent e) {
return false;
}
#Override
public void onShowPress(MotionEvent e) {
}
#Override
public boolean onSingleTapUp(MotionEvent e) {
// Log.d("GESTURE DETECTED", "ACTION UP" + e);
return true;
}
#Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
return false;
}
#Override
public void onLongPress(MotionEvent e) {
//Log.d("GESTURE DETECTED", "LONG PRESS");
if(rv.getScrollState() == SCROLL_STATE_IDLE && !(rv.getScrollState() == SCROLL_STATE_DRAGGING)) {
View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
if (child != null && mListener != null) {
mListener.onLongClick(child, recyclerView.getChildLayoutPosition(child));
}
}
}
#Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
return false;
}
});
}
#Override
public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
//Log.d("Intercept Event", "INTERCEPTING \n" + e);
if(rv.getScrollState() == SCROLL_STATE_IDLE && !(rv.getScrollState() == SCROLL_STATE_DRAGGING)) {
View child = rv.findChildViewUnder(e.getX(), e.getY());
if (child != null && mListener != null && gestureDetector.onTouchEvent(e)) {
mListener.click(child, rv.getChildLayoutPosition(child));
}
}
//true if onTouchEvent is to be called, false if you want gesture detector to handle events
return false;
}
#Override
public void onTouchEvent(RecyclerView rv, MotionEvent e) {
}
#Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}
}
}
Any help would be greatly appreciated!!

You need to be setting the play/pause/whatever visibility in onBindViewHolder or else it will be whatever the last setting was even though a new model object is bound to that view.

Deleting all items in a page one by one in Android recyclerview does not load the next set of data

I have implemented recyclerview and it loads 10 tasks at a time. Once every task is completed, I am removing the task with a completed button. It loads the 11th item if I scroll to the bottom at one condition there has to be atleast one uncompleted task present on the page. If I clear all 10 items it just shows me loading animation and nothing happens. I have to close the app and open again to load the tasks again.
I have implemented a PaginationActivity, PaginationAdapter and scroll listener for the page. It loads data from a local database whenever you have reached the end of the page and you have got more tasks to load.
PaginationActivity.java
public class PaginationActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
PaginationAdapter adapter;
LinearLayoutManager linearLayoutManager;
public static ArrayList<String> reasonsdata = new ArrayList<String>();
public static String rslt="";
public static String[] reasons;
public static boolean chk = true;
public static String payTypeSelected;
public static String reasonSelected;
public static HashMap<String, EditText> drivernotesMap = new HashMap<String, EditText>();
public static HashMap<String, EditText> paynoteMap = new HashMap<String, EditText>();
public static HashMap<String, String> paytypeMap = new HashMap<String, String>();
RecyclerView rv;
ProgressBar progressBar;
private static final int PAGE_START = 0;
private boolean isLoading = false;
private boolean isLastPage = false;
private int TOTAL_PAGES;
private int currentPage = PAGE_START;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pagination_main);
fillspinner();
rv = (RecyclerView) findViewById(R.id.main_recycler);
progressBar = (ProgressBar) findViewById(R.id.main_progress);
adapter = new PaginationAdapter(this);
linearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
rv.setLayoutManager(linearLayoutManager);
rv.setItemAnimator(new DefaultItemAnimator());
rv.setAdapter(adapter);
rv.addOnScrollListener(new PaginationScrollListener(linearLayoutManager) {
#Override
protected void loadMoreItems() {
isLoading = true;
currentPage += 1;
// mocking network delay for API call
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
loadNextPage();
}
}, 1000);
}
#Override
public int getTotalPageCount() {
return TOTAL_PAGES;
}
#Override
public boolean isLastPage() {
return isLastPage;
}
#Override
public boolean isLoading() {
return isLoading;
}
});
// mocking network delay for API call
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
loadFirstPage();
}
}, 1000);
}
private void fillspinner() {
reasonsdata.clear();
try
{
rslt="START";
CallReasons cr = new CallReasons();
cr.join();
cr.start();
while(rslt=="START") {
try {
Thread.sleep(10);
}catch(Exception ex) {
}
}
}
catch (Exception ex) {
ex.printStackTrace();
}
if(rslt == "Success"){
reasonsdata.add("<--- Select Reason --->");
for(int i =0; i< reasons.length;i++){
reasonsdata.add(reasons[i]);
}
}
}
public void loadFirstPage() {
Log.d(TAG, "loadFirstPage: ");
TOTAL_PAGES = Run.getTotalPages();
//List<Run> runs = Run.createRuns(adapter.getItemCount());
List<Run> runs = Run.createRuns(adapter.getMaxID());
progressBar.setVisibility(View.GONE);
adapter.addAll(runs);
if (currentPage <= TOTAL_PAGES) adapter.addLoadingFooter();
else isLastPage = true;
}
public void loadNextPage() {
Log.d(TAG, "loadNextPage: " + currentPage);
//List<Run> runs = Run.createRuns(adapter.getItemCount());
List<Run> runs = Run.createRuns(adapter.getMaxID());
adapter.removeLoadingFooter();
isLoading = false;
adapter.addAll(runs);
if (currentPage != TOTAL_PAGES) adapter.addLoadingFooter();
else isLastPage = true;
}
}
PaginationAdapter.java
public class PaginationAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private static final int ITEM = 0;
private static final int LOADING = 1;
private List<Run> runs = new ArrayList<>();
private Context context;
private boolean isLoadingAdded = false;
private String cash = "CASH";
private String cheque = "CHEQUE";
SQLiteDatabase db;
//PaginationActivity func_call;
public PaginationAdapter(Context context) {
this.context = context;
runs = new ArrayList<>();
//func_call = new PaginationActivity();
}
public List<Run> getRuns() {
return runs;
}
public void setRuns(List<Run> runs) {
this.runs = runs;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
RecyclerView.ViewHolder viewHolder = null;
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
switch (viewType) {
case ITEM:
viewHolder = getViewHolder(parent, inflater);
break;
case LOADING:
View v2 = inflater.inflate(R.layout.item_progress, parent, false);
viewHolder = new LoadingVH(v2);
//viewHolder = getViewHolder(parent, inflater);
//func_call.loadNextPage();
break;
}
return viewHolder;
}
#NonNull
private RecyclerView.ViewHolder getViewHolder(ViewGroup parent, LayoutInflater inflater) {
RecyclerView.ViewHolder viewHolder;
View v1 = inflater.inflate(R.layout.activity_main, parent, false);
viewHolder = new RunVH(v1);
return viewHolder;
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
final Run run = runs.get(position);
switch (getItemViewType(position)) {
case ITEM:
final RunVH runVH = (RunVH) holder;
//adding text areas to show data
//Completed task button
runVH.btnSave.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Toast.makeText(context, "Mark as Completed", Toast.LENGTH_LONG).show();
remove(run);
}
}
} catch (Exception ex) {
//pbbar.setVisibility(View.GONE);
ex.printStackTrace();
}
}
});
break;
case LOADING:
break;
}
}
#Override
public int getItemCount() {
return runs == null ? 0 : runs.size();
}
//#Override
public int getMaxID() {
if(runs == null || runs.size() == 0){
return 0;
}else{
Run test = runs.get(runs.size()-2);
int maxid = (int) test.getProperty(0);
return maxid;
}
}
#Override
public int getItemViewType(int position) {
return (position == runs.size() - 1 && isLoadingAdded) ? LOADING : ITEM;
}
public void add(Run run) {
runs.add(run);
notifyItemInserted(runs.size() - 1);
}
public void addAll(List<Run> runList) {
for (Run run : runList) {
add(run);
}
}
public void remove(Run run) {
int position = runs.indexOf(run);
if (position > -1) {
runs.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, runs.size());
}
/*if(runs.size() < 0){
clear();
func_call.loadNextPage();
}*/
}
public void clear() {
isLoadingAdded = false;
while (getItemCount() > 0) {
remove(getItem(0));
}
}
public boolean isEmpty() {
return getItemCount() == 0;
}
public void addLoadingFooter() {
isLoadingAdded = true;
add(new Run());
}
public void removeLoadingFooter() {
isLoadingAdded = false;
int position = runs.size() - 1;
Run item = getItem(position);
if (item != null) {
runs.remove(position);
notifyItemRemoved(position);
}
}
public Run getItem(int position) {
return runs.get(position);
}
protected class RunVH extends RecyclerView.ViewHolder {
private TextView textEsky;
private TextView textAdjusted;
private TextView textAddress;
private TextView textNew;
private TextView textTrusted;
private TextView textName;
private TextView textMobile;
private TextView textHome;
private TextView textWork;
private TextView payType;
private EditText textPayNote;
private EditText textDeliveryInst;
private EditText textDriverNotes;
private final Spinner reasons;
private RadioGroup rg;
private Button btnSave;
private CheckBox IsDriverData;
public RunVH(View itemView) {
super(itemView);
textEsky = (TextView) itemView.findViewById(R.id.idEsky);
textAdjusted = (TextView) itemView.findViewById(R.id.idAdjusted);
textAddress = (TextView) itemView.findViewById(R.id.idAddress);
textNew = (TextView) itemView.findViewById(R.id.idNew);
textTrusted = (TextView) itemView.findViewById(R.id.idTrusted);
textName = (TextView) itemView.findViewById(R.id.idName);
textMobile = (TextView) itemView.findViewById(R.id.idMobile);
textHome = (TextView) itemView.findViewById(R.id.idHome);
textWork = (TextView) itemView.findViewById(R.id.idWork);
payType = (TextView) itemView.findViewById(R.id.idPayType);
textPayNote = (EditText) itemView.findViewById(R.id.idPayNoteText);
textDeliveryInst = (EditText) itemView.findViewById(R.id.idDeliInsText);
textDriverNotes = (EditText) itemView.findViewById(R.id.idDriverNotesText);
IsDriverData = (CheckBox) itemView.findViewById(R.id.idCheckBox);
reasons = (Spinner) itemView.findViewById(R.id.idReason);
rg = (RadioGroup) itemView.findViewById(R.id.Radiogroup);
btnSave = (Button) itemView.findViewById(R.id.button);
}
}
protected class LoadingVH extends RecyclerView.ViewHolder {
public LoadingVH(View itemView) {
super(itemView);
}
}
}
PaginationScrollListener.java
public abstract class PaginationScrollListener extends RecyclerView.OnScrollListener {
LinearLayoutManager layoutManager;
public PaginationScrollListener(LinearLayoutManager layoutManager) {
this.layoutManager = layoutManager;
}
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int visibleItemCount = layoutManager.getChildCount();
int totalItemCount = layoutManager.getItemCount();
int firstVisibleItemPosition = layoutManager.findFirstVisibleItemPosition();
if (!isLoading() && !isLastPage()) {
if ((visibleItemCount + firstVisibleItemPosition) >= totalItemCount
&& firstVisibleItemPosition >= 0) {
loadMoreItems();
}
}
}
protected abstract void loadMoreItems();
public abstract int getTotalPageCount();
public abstract boolean isLastPage();
public abstract boolean isLoading();
}

I could be wrong, but it looks to me like the only time you call loadNextPage() is when the RecyclerView gets a scroll event. Removing ViewHolders doesn't cause scroll events iirc.
If you register an AdapterDataObserver on the PaginationAdapter, you can listen in on removal/add events and trigger loads when there aren't any tasks left. You could probably do the same thing with some small changes to that commented-out code in remove(Run):
if (runs.isEmpty()) {
func_call.loadNextPage();
}
EDIT:
Btw, you see where you called adapter = new PaginationAdapter(this); in the PaginationActivity.onCreate method? The this here is your PaginationActivity, which means you can assign it to a PaginationAdapter field like so:
/**
* #param context the activity this adapter will appear in
*/
public PaginationAdapter(Context context) {
this.context = context;
runs = new ArrayList<>();
func_call = (PaginationActivity)context;
}
That should be enough to prevent crashes. For better separation of concerns, you'll probably want to switch over to AdapterDataObserver-based logic (I think this is called the open/closed principle? Maybe?).

RecyclerView fling and move not smooth

i am chinese coder.i am not good at english,so just try hard to describe the question. thank you very much for your answer.
when i first into activity with RecyclerView and scroll,it is not smooth especially showing next item next ,but when i have scrolled the Recyclerview,it is work,and smooth . some coder say we can't do much work on onCreateViewHolder() and onBindViewHolder() , but i can not get it.
here is my code:
fragment
public class HomeFragment extends RefreshableFragment implements IHomeView {
#Bind(R.id.refresh_view)
PullToRefreshRecyclerView refresh_view;
private RecyclerView refreshableView;
private HomePresenter homePresenter;
#Override
public View initSuccessView() {
View view = View.inflate(getContext(), R.layout.fragment_refreshable_success_recyclerview, null);
ButterKnife.bind(this, view);
initRefreshLayout();
initRecyclerView();
return view;
}
/**
* 初始化可刷新控件
*/
private void initRefreshLayout() {
refresh_view.setMode(PullToRefreshBase.Mode.BOTH);
refresh_view.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<RecyclerView>() {
#Override
public void onPullDownToRefresh(PullToRefreshBase<RecyclerView> refreshView) {
homePresenter.refresh();
}
#Override
public void onPullUpToRefresh(PullToRefreshBase<RecyclerView> refreshView) {
homePresenter.loadMore();
}
});
}
/**
* 初始化RecyclerView控件
*/
private void initRecyclerView() {
refreshableView = refresh_view.getRefreshableView();
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext(),LinearLayoutManager.VERTICAL,false);
SpaceItemDecoration decor = new SpaceItemDecoration(2);
refreshableView.addItemDecoration(decor);
refreshableView.setLayoutManager(layoutManager);
refreshableView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
int childCount = recyclerView.getChildCount();
for (int i = 0; i < childCount; i++) {
View view = recyclerView.getChildAt(i);
RecyclerView.ViewHolder holder = recyclerView.getChildViewHolder(view);
switch (holder.getItemViewType()){
case HomeAdapter.TYPE_TOPIC:
HomeTopicViewHolder topicViewHolder = (HomeTopicViewHolder) holder;
topicViewHolder.setParentHeight(recyclerView.getHeight());
topicViewHolder.setOffset();
}
}
}
});
}
#Override
protected void requestNetwork() {
homePresenter = new HomePresenter(getContext(),this,null);
homePresenter.init();
}
#Override
public RecyclerView getRecyclerView() {
return refreshableView;
}
#Override
public RefreshView getRefreshView() {
return getParentRefreshView();
}
#Override
public void onRefreshFinish() {
if(refresh_view.isRefreshing()){
refresh_view.onRefreshComplete();
}
}
#Override
public void onLordMoreFinish() {
}
}
presenter
public class HomePresenter extends BasePresenter<IHomeView> implements IHomePresenter, StringLoaderCallback {
private Gson gson;
private HomeAdapter homeAdapter;
private final Pagination pagination;
public HomePresenter(Context context,IHomeView homeView,Bundle bundle) {
super(context,homeView,bundle);
gson = new Gson();
homeAdapter = new HomeAdapter();
getPresenterView().getRecyclerView().setAdapter(homeAdapter);
pagination = new Pagination();
pagination.setLimit(10);
pagination.setOffset(0);
}
#Override
public void init() {
String bannerUrl = ServerAPI.Home.buildHomeBannerUrl();
NetworkStringLoader.getInstance(context).sendGetStringRequest(bannerUrl, null, bannerUrl, this);
String topicUrl = ServerAPI.Home.buildHomeTopicUrl();
NetworkStringLoader.getInstance(context).sendGetStringRequest(topicUrl, null, topicUrl, this);
String routeUrl = ServerAPI.Home.buildHomeRouteUrl();
NetworkStringLoader.getInstance(context).sendGetStringRequest(routeUrl, pagination.getMap(), REFRESH, this);
}
#Override
public void loadMore() {
String routeUrl = ServerAPI.Home.buildHomeRouteUrl();
pagination.setOffset(pagination.getTotal());
pagination.setLimit(10);
NetworkStringLoader.getInstance(context).sendGetStringRequest(routeUrl, pagination.getMap(), LOADMORE, this);
}
#Override
public void refresh() {
pagination.setOffset(0);
pagination.setLimit(10);
pagination.clearTotal();
init();
}
#Override
public void onLoadFinished(String url,Map<String,String> params, String data,Object tag) {
if(url.equals(ServerAPI.Home.buildHomeBannerUrl())){
Log.i(url,data);
HomeBanner.HomeBannerLists homeBannerLists = gson.fromJson(data,HomeBanner.HomeBannerLists.class);
homeAdapter.setBanners(homeBannerLists.list);
}
if(url.equals(ServerAPI.Home.buildHomeTopicUrl())){
Log.i(url,data);
HomeTopic.HomeTopicLists homeTopicLists = gson.fromJson(data,HomeTopic.HomeTopicLists.class);
homeAdapter.setTopics(homeTopicLists.list);
}
if(url.equals(ServerAPI.Home.buildHomeRouteUrl())){
Log.i(url,data);
int mode = (int) tag;
HomeRoute.HomeRouteLists homeRouteLists = gson.fromJson(data, HomeRoute.HomeRouteLists.class);
if (mode == REFRESH){
homeAdapter.setRoutes(homeRouteLists.list);
} else if(mode == LOADMORE){
homeAdapter.appendRoutes(homeRouteLists.list);
}
pagination.appendTotal(homeRouteLists.list.size());
}
getPresenterView().getRefreshView().setCurrentState(RefreshView.STATE_SUCCESS);
getPresenterView().onRefreshFinish();
}
#Override
public void onLoadError(VolleyError error) {
Log.i("error",error.getMessage());
}
}
adapter
public class HomeAdapter extends RecyclerView.Adapter {
public static final int TYPE_BANNER = 0;
public static final int TYPE_TOPIC = 1;
public static final int TYPE_ROUTE = 2;
private List<HomeBanner> banners = new ArrayList<>();
private List<HomeTopic> topics = new ArrayList<>();
private List<HomeRoute> routes = new ArrayList<>();
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
switch (viewType){
case TYPE_BANNER:
View bannerView = HomeBannerViewHolder.getView(parent.getContext());
return new HomeBannerViewHolder(bannerView);
case TYPE_TOPIC:
View topicView = View.inflate(parent.getContext(), R.layout.item_home_topic,null);
// View topicView = HomeTopicViewHolder.getView(parent.getContext());
return new HomeTopicViewHolder(topicView);
case TYPE_ROUTE:
View routeView = View.inflate(parent.getContext(), R.layout.item_home_route,null);
// View routeView = HomeRouteViewHolder.getView(parent.getContext());
return new HomeRouteViewHolder(routeView);
default:
// View defaultView = new View(parent.getContext());
View view = EmptyViewHolder.getView(parent.getContext());
return new EmptyViewHolder(view);
}
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if(position == 0){
onBindBannerViewHolder(holder);
}else if(position>0 && position<topics.size()+1){
onBindTopicViewHolder(holder,position-1);
}else {
onBindRouteViewHolder(holder,position-topics.size()-1);
}
}
private void onBindRouteViewHolder(RecyclerView.ViewHolder holder, int position) {
HomeRouteViewHolder routeViewHolder = (HomeRouteViewHolder) holder;
routeViewHolder.setData(routes.get(position));
}
private void onBindTopicViewHolder(RecyclerView.ViewHolder holder,int position) {
HomeTopicViewHolder topicViewHolder = (HomeTopicViewHolder) holder;
topicViewHolder.setData(topics.get(position));
}
private void onBindBannerViewHolder(RecyclerView.ViewHolder holder) {
HomeBannerViewHolder bannerViewHolder = (HomeBannerViewHolder) holder;
bannerViewHolder.setData(banners);
}
#Override
public int getItemCount() {
return 1 + topics.size()+routes.size();
}
#Override
public int getItemViewType(int position) {
if(position == 0){
return TYPE_BANNER;
}else if(position<topics.size()+1){
return TYPE_TOPIC;
}else {
return TYPE_ROUTE;
}
}
public void setBanners(List<HomeBanner> list){
banners.clear();
banners.addAll(list);
notifyDataSetChanged();
}
public void setTopics(List<HomeTopic> list) {
topics.clear();
topics.addAll(list);
notifyDataSetChanged();
}
public void setRoutes(List<HomeRoute> list) {
routes.clear();
routes.addAll(list);
notifyDataSetChanged();
}
public void appendRoutes(List<HomeRoute> list) {
routes.addAll(routes.size(),list);
notifyItemRangeInserted(getItemCount(),list.size());
}
}
holder
public class HomeTopicViewHolder extends BaseViewHolder<HomeTopic> {
private static SimpleDraweeView content_iv ;
private static TextView home_topic_title ;
private static TextView home_topic_discription ;
private int height;
public static View getView(Context context) {
View topicView = View.inflate(context, R.layout.item_home_topic,null);
return topicView;
}
public HomeTopicViewHolder(View itemView) {
super(itemView);
content_iv = (SimpleDraweeView) itemView.findViewById(R.id.home_topic_iv);
if(content_iv!=null){
content_iv = (SimpleDraweeView) itemView.findViewById(R.id.home_topic_iv);
}
if(home_topic_title!=null){
home_topic_title = (TextView) itemView.findViewById(R.id.home_topic_title);
}
if(home_topic_discription!=null){
home_topic_discription = (TextView) itemView.findViewById(R.id.home_topic_discription);
}
if(height==0){
SharedPreferences sp = SharedPreferenceHelper.getInstance().getSharedPreference(itemView.getContext(), SharedPreferenceHelper.EnumSPName.CONFIG);
int scale = sp.getInt(SharedPreferenceHelper.EnumSPName.windowWidth, 0);
FrameLayout.LayoutParams layoutParams = new FrameLayout.LayoutParams(scale,scale);
content_iv.setLayoutParams(layoutParams);
}
}
#Override
protected void inflateView(HomeTopic data) {
NetworkImageLoader loader = NetworkImageLoader.getInstance();
loader.setUrlToSimpleDraweeView(data.getImage(),content_iv);
home_topic_title.setText(data.getName());
home_topic_discription.setText(String.format(getResources().getString(R.string.guider_route),data.getGuide(), data.getRoute()));
}
public void setOffset() {
int itemViewHeight = itemView.getHeight();
int imageViewHeight = content_iv.getHeight();
int parentOffsetMax = (getParentHeight() + itemViewHeight) / 2;
int offsetMax = imageViewHeight - itemViewHeight;
float y = itemView.getY();
float location = y + itemViewHeight/2;
float v = location - getParentHeight() / 2;
float percent = v/parentOffsetMax;
int margin = (int) ((offsetMax/2)*(percent + 1));
FrameLayout.LayoutParams layoutParams = (FrameLayout.LayoutParams) content_iv.getLayoutParams();
layoutParams.setMargins(0,-margin,0,0);
content_iv.setLayoutParams(layoutParams);
}
public void setParentHeight(int height) {
this.height = height;
}
public int getParentHeight() {
return height;
}
}