I’m trying to pass the position of the card to SlideView Activity where onMenuItemClick was used to bring up the correct information about that specific card. Currently, I’m using getAdapterPosition in onMenuItemClick within my Adapter, but thats resulting in the last element drawn to screen being saved to my adapterPosition. I understand why it’s giving the last position, but unsure how to set the correct position. Should I try to save and pass the position via showPopupMenu or something else entirely? Below are my Adapter & MainActivity.
Adapter:
public class Adapter extends RecyclerView.Adapter<Adapter.MyViewHolder> {
private Context mContext;
private List<Properties> dogList;
private MyViewHolder holder;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView title, count;
public ImageView thumbnail, overflow;
public MyViewHolder(View view) {
super(view);
title = (TextView) view.findViewById(R.id.title);
count = (TextView) view.findViewById(R.id.count);
thumbnail = (ImageView) view.findViewById(R.id.thumbnail);
overflow = (ImageView) view.findViewById(R.id.overflow);
}
}
public Adapter(Context mContext, List<Properties> dogList) {
this.mContext = mContext;
this.dogList = dogList;
}
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.card, parent, false);
return new MyViewHolder(itemView);
}
#Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
this.holder=holder;
Properties dog = dogList.get(position);
holder.title.setText(dog.getName());
// loading dog cover using Glide library
Glide.with(mContext).load(dog.getThumbnail()).into(holder.thumbnail);
holder.overflow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
showPopupMenu(holder.overflow);
}
});
}
/**
* Showing popup menu when tapping on icon
*/
private void showPopupMenu(View view) {
// inflate menu
PopupMenu popup = new PopupMenu(mContext, view);
MenuInflater inflater = popup.getMenuInflater();
inflater.inflate(R.menu.menu, popup.getMenu());
popup.setOnMenuItemClickListener(new MyMenuItemClickListener());
popup.show();
}
/**
* Click listener for popup menu items
*/
class MyMenuItemClickListener implements PopupMenu.OnMenuItemClickListener {
public MyMenuItemClickListener() {
}
#Override
public boolean onMenuItemClick(MenuItem menuItem) {
switch (menuItem.getItemId()) {
case R.id.action_add_favourite:
Toast.makeText(mContext, "Add to favourite", Toast.LENGTH_SHORT).show();
return true;
case R.id.action_more_info:
Intent slideStart = new Intent(mContext, SlideViewActivity.class);
super.getClass();
int adapterPosition = holder.getAdapterPosition();
slideStart.putExtra("position", adapterPosition);
slideStart.putExtra("list", (Serializable) dogList);
mContext.startActivity(slideStart);
return true;
default:
}
return false;
}
}
#Override
public int getItemCount() {
return dogList.size();
}
}
MainActivity:
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private RecyclerView recyclerView;
private Adapter adapter;
private List<Properties> dogList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
initCollapsingToolbar();
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
dogList = new ArrayList<>();
adapter = new Adapter(this, dogList);
RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(this, 2);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.addItemDecoration(new GridSpacingItemDecoration(2, dpToPx(10), true));
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(adapter);
prepareCards();
try {
Glide.with(this).load(R.drawable.austrailian_shepherd).into((ImageView) findViewById(R.id.backdrop));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Initializing collapsing toolbar
* Will show and hide the toolbar title on scroll
*/
private void initCollapsingToolbar() {
final CollapsingToolbarLayout collapsingToolbar =
(CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
collapsingToolbar.setTitle(" ");
AppBarLayout appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
appBarLayout.setExpanded(true);
// hiding & showing the title when toolbar expanded & collapsed
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
boolean isShow = false;
int scrollRange = -1;
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
if (scrollRange == -1) {
scrollRange = appBarLayout.getTotalScrollRange();
}
if (scrollRange + verticalOffset == 0) {
collapsingToolbar.setTitle(getString(R.string.app_name));
isShow = true;
} else if (isShow) {
collapsingToolbar.setTitle(" ");
isShow = false;
}
}
});
}
private void prepareCards() {
int librarySize = getResources().getStringArray(R.array.titles).length;
for(int i=0;i<librarySize;i++) {
String dognames = getResources().getStringArray(R.array.titles)[i];
String doginfo = getResources().getStringArray(R.array.info)[i];
int imageId = getResources().getIdentifier(dognames.toLowerCase(Locale.getDefault()), "drawable", this.getPackageName());
Properties a = new Properties(dognames, doginfo, imageId);
dogList.add(a);
}
adapter.notifyDataSetChanged();
}
#Override
public void onClick(View v) {
}
/**
* RecyclerView item decoration - give equal margin around grid item
*/
public class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {
private int spanCount;
private int spacing;
private boolean includeEdge;
public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.includeEdge = includeEdge;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view); // item position
int column = position % spanCount; // item column
if (includeEdge) {
outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)
if (position < spanCount) { // top edge
outRect.top = spacing;
}
outRect.bottom = spacing; // item bottom
} else {
outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f / spanCount) * spacing)
if (position >= spanCount) {
outRect.top = spacing; // item top
}
}
}
}
/**
* Converting dp to pixel
*/
private int dpToPx(int dp) {
Resources r = getResources();
return Math.round(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics()));
}
}
Try these modifications :
holder.overflow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
showPopupMenu(holder.overflow, position);
}
});
private void showPopupMenu(View view, int pos) {
// inflate menu
PopupMenu popup = new PopupMenu(mContext, view);
MenuInflater inflater = popup.getMenuInflater();
inflater.inflate(R.menu.menu, popup.getMenu());
popup.setOnMenuItemClickListener(new MyMenuItemClickListener(pos));
popup.show();
}
class MyMenuItemClickListener implements PopupMenu.OnMenuItemClickListener {
int pos;
public MyMenuItemClickListener(int pos) {
this.pos = pos;
}
#Override
public boolean onMenuItemClick(MenuItem menuItem) {
switch (menuItem.getItemId()) {
case R.id.action_add_favourite:
Toast.makeText(mContext, "Add to favourite", Toast.LENGTH_SHORT).show();
return true;
case R.id.action_more_info:
Intent slideStart = new Intent(mContext, SlideViewActivity.class);
super.getClass();
slideStart.putExtra("position", pos);
slideStart.putExtra("list", (Serializable) dogList);
mContext.startActivity(slideStart);
return true;
default:
}
return false;
}
}
Related
I have an issue with Recyclerview item selection , which is set up in a fragment , the problem is each page which is created by ViewVager has its own instance of the Recyclerview so the output is that selecting Recyclerview items will reset the scroll state of the Recyclerview, so I'm looking for a solution to to save scroll state of a Recyclerview when an item is clicked.
Fragment onViewCreated
// setting RecyclerView
mEpisodesList = (CustomRecyclerView) view.findViewById(R.id.episodesLIST);
// getting episodeslist
ArrayList<PlanetModel> episodeslist = new ArrayList<>();
for (TvShowEpisode e : mEpisodes) {
episodeslist.add(new PlanetModel(e.mEpisode));
}
// Setting LinearLayoutManager
LinearLayoutManager layoutManager
= new LinearLayoutManager(mContext.getApplicationContext(), LinearLayoutManager.HORIZONTAL, false);
//mEpisodesList.setLayoutManager(new LinearLayoutManager(mContext));
mEpisodesList.setLayoutManager(layoutManager);
// Setting RecyclerView Adapter
int currentPosition = getArguments().getInt("position");
planetAdapter = new PlanetAdapter(episodeslist, currentPosition, new PlanetAdapter.OnItemClickListener() {
#Override
public void onItemClick(final int pos) {
int scrollValue = mEpisodesList.getHorizontalScrollOffset();
mCallback.sendText(pos, scrollValue);
}
});
mEpisodesList.setAdapter(planetAdapter);
int scrollValue = getArguments().getInt("scrollValue");
new Handler().postDelayed(() -> mEpisodesList.scrollBy(scrollValue, 0), 100);
activity
public class TvShowEpisodeDetails extends MizActivity implements TvShowEpisodeDetailsFragment.TextClicked {
#Override
protected int getLayoutResource() {
return R.layout.viewpager_with_toolbar_overlay;
}
#Override
public void onCreate(Bundle savedInstanceState) {
mBus = MizuuApplication.getBus();
super.onCreate(savedInstanceState);
// Set theme
setTheme(R.style.Mizuu_Theme_NoBackground);
ViewUtils.setupWindowFlagsForStatusbarOverlay(getWindow(), true);
ViewUtils.setProperToolbarSize(this, mToolbar);
mShowId = getIntent().getExtras().getString(SHOW_ID);
mSeason = getIntent().getExtras().getInt("season");
mEpisode = getIntent().getExtras().getInt("episode");
mDatabaseHelper = MizuuApplication.getTvEpisodeDbAdapter();
Cursor cursor = mDatabaseHelper.getEpisodes(mShowId);
try {
while (cursor.moveToNext()) {
mEpisodes.add(new TvShowEpisode(this, mShowId,
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_TITLE)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_PLOT)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_SEASON)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_AIRDATE)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_DIRECTOR)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_WRITER)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_GUESTSTARS)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_EPISODE_RATING)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_HAS_WATCHED)),
cursor.getString(cursor.getColumnIndex(DbAdapterTvShowEpisodes.KEY_FAVOURITE))
));
}
} catch (Exception e) {
} finally {
cursor.close();
}
final ArrayList<PlanetModel> episodeslist = new ArrayList<>();
for (TvShowEpisode e : mEpisodes) {
episodeslist.add(new PlanetModel(e.mEpisode));
}
mShowTitle = MizuuApplication.getTvDbAdapter().getShowTitle(mShowId);
setTitle(mShowTitle);
mViewPager = (ViewPager) findViewById(R.id.awesomepager);
mViewPager.setAdapter(new TvShowEpisodeDetailsAdapter(getSupportFragmentManager()));
for (int i = 0; i < mEpisodes.size(); i++)
fragments.add(TvShowEpisodeDetailsFragment
.newInstance(mShowId, Integer.parseInt(mEpisodes.get(i).getSeason()), Integer.parseInt(mEpisodes.get(i).getEpisode()), i, mScrollValue));
mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
#Override
public void onPageSelected(int position) {
for (int i = 0; i < episodeslist.size(); i++) {
episodeslist.get(i).setPlanetSelected(false);
}
episodeslist.get(position).setPlanetSelected(true);
//notify your recycler views adaper
ViewUtils.updateToolbarBackground(TvShowEpisodeDetails.this, mToolbar, 0, mEpisodes.get(position).getTitle(), Color.TRANSPARENT);
}
});
if (savedInstanceState != null) {
mViewPager.setCurrentItem(savedInstanceState.getInt("tab", 0));
} else {
for (int i = 0; i < mEpisodes.size(); i++) {
if (mEpisodes.get(i).getSeason().equals(MizLib.addIndexZero(mSeason)) && mEpisodes.get(i).getEpisode().equals(MizLib.addIndexZero(mEpisode))) {
mViewPager.setCurrentItem(i);
SharedPreferences setPref = this.getSharedPreferences("TvShowEpisodeDetails", Context.MODE_PRIVATE);
setPref.edit().putInt("i", i).apply();
break;
}
}
}
}
private class TvShowEpisodeDetailsAdapter extends FragmentPagerAdapter {
public TvShowEpisodeDetailsAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
// return TvShowEpisodeDetailsFragment.newInstance(mShowId, Integer.parseInt(mEpisodes.get(index).getSeason()), Integer.parseInt(mEpisodes.get(index).getEpisode()));
return fragments.get(index);
}
#Override
public int getCount() {
return mEpisodes.size();
}
}
Recyclerview adapter
public class PlanetAdapter extends RecyclerView.Adapter<PlanetAdapter.PlanetViewHolder> {
public interface OnItemClickListener {
void onItemClick(int item);
}
private final ArrayList<PlanetModel> episodeslist;
private final OnItemClickListener listener;
SharedPreferences getPref = getContext().getSharedPreferences("TvShowEpisodeDetails", Context.MODE_PRIVATE);
int pos = getPref.getInt("i", 0);
int isPlanetSelected = pos;
private final int highlightedPos;
public PlanetAdapter(ArrayList<PlanetModel> episodeslist, int highlightedPosition, OnItemClickListener listener) {
this.episodeslist = episodeslist;
this.listener = listener;
this.highlightedPos = highlightedPosition;
}
#NonNull
#Override
public PlanetAdapter.PlanetViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.planet_row, parent, false);
return new PlanetViewHolder(v);
}
#Override
public void onBindViewHolder(PlanetAdapter.PlanetViewHolder vh, final int position) {
TextView tv = (TextView) vh.itemView;
PlanetModel planetModel = episodeslist.get(position);
tv.setText(planetModel.getPlanetName());
tv.setCompoundDrawablesWithIntrinsicBounds(R.drawable.bg, 0, 0, 0);
if (highlightedPos == position) {
vh.itemView.setBackgroundColor(getContext().getResources().getColor(R.color.colorPrimaryLight));
} else {
vh.itemView.setBackgroundColor(getContext().getResources().getColor(R.color.colorPrimaryDark));
}
//holder.image.setImageResource(R.drawable.planetimage);
//vh.text.setText(episodeslist.get(position).toString());
}
#Override
public int getItemCount() {
return episodeslist.size();
}
public class PlanetViewHolder extends RecyclerView.ViewHolder {
protected TextView text;
public PlanetViewHolder(View itemView) {
super(itemView);
text = (TextView) itemView.findViewById(R.id.text_id);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.d("LOG_TAG", "onClick: current item: " + highlightedPos);
final int previousItem = isPlanetSelected;
isPlanetSelected = getPosition();
SharedPreferences setPref = v.getContext().getSharedPreferences("PlanetAdapter", Context.MODE_PRIVATE);
setPref.edit().putInt("newPosition", getPosition()).apply();
listener.onItemClick(getPosition());
}
});
}
// public void bind(final PlanetModel item, final OnItemClickListener listener) {
// }
}
You can solve this by tracking the current scroll value of the RecyclerView, and whenever you hit an a ReyclerView item; add a new parameter to the listener callback with this tracked scroll value to update the new fragment that will be shown on the ViewPager.
Track the scroll value:
mEpisodesList.setOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
scrollValue += dx;
}
});
Pass it as interface callback:
planetAdapter = new PlanetAdapter(episodeslist, currentPosition, new PlanetAdapter.OnItemClickListener() {
#Override
public void onItemClick(final int pos) {
mCallback.sendText(pos, scrollValue);
}
});
And update that in the list of ViewPager fragments before scrolling to the new page:
#Override
public void sendText(int position, int scrollValue) {
mScrollValue = scrollValue;
TvShowEpisodeDetailsFragment frag = fragments.get(position);
Bundle arguments = frag.getArguments();
arguments.putInt("scrollValue", scrollValue);
mViewPager.setCurrentItem(position, false);
}
try this
// save
recyclerViewState = binding.mainList.layoutManager?.onSaveInstanceState()
// restore
recyclerViewState?.let {
binding.mainList.layoutManager?.onRestoreInstanceState(it)
}
I get this error in the LogCat when I try to run the application.
java.lang.IllegalArgumentException: Context must not be null.
This happens when I add the Picasso code in the class.
here is the adpater.Java
It says the Context is null, I have read other posts but I could not find a solution.
public class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder>{
private List<App> mApps;
private boolean mHorizontal;
private boolean mPager;
private Context mContext;
public Adapter(Context ctx, boolean horizontal, boolean pager, List<App> apps) {
mHorizontal = horizontal;
mApps = apps;
mPager = pager;
this.mContext=ctx;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (mPager) {
return new ViewHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.adaper_pager, parent, false));
} else {
return mHorizontal ? new ViewHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.adapter, parent, false)) :
new ViewHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.adapter_vertical, parent, false));
}
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
App app = mApps.get(position);
//holder.imageView.setImageResource(app.getDrawable());
Picasso.with(mContext).load(app.getLink()).into(holder.imageView);
holder.nameTextView.setText(app.getName());
holder.ratingTextView.setText(String.valueOf(app.getRating()));
}
#Override
public int getItemViewType(int position) {
return super.getItemViewType(position);
}
#Override
public int getItemCount() {
return mApps.size();
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public ImageView imageView;
public TextView nameTextView;
public TextView ratingTextView;
public ViewHolder(View itemView) {
super(itemView);
imageView = (ImageView) itemView.findViewById(R.id.igOne);
nameTextView = (TextView) itemView.findViewById(R.id.nameTV);
ratingTextView = (TextView) itemView.findViewById(R.id.rate);
}
}
}
Please Help. some say it is because the imageView is null. I have no idea about that.
MainActivity
public class MainActivity extends AppCompatActivity implements Toolbar.OnMenuItemClickListener {
private static final String TAG = "MainActivity";
private Context mContext = MainActivity.this;
private static final int ACTIVITY_NUM = 0;
public static final String ORIENTATION = "orientation";
private RecyclerView mRecyclerView;
private boolean mHorizontal;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(TAG, "OnCreate: Starting MainActivity");
setupBottomNavigationView();
mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
mRecyclerView.setHasFixedSize(true);
if (savedInstanceState == null) {
mHorizontal = true;
} else {
mHorizontal = savedInstanceState.getBoolean(ORIENTATION);
}
setupAdapter();
}
/**
* Setup Bottom Navigation View
*/
private void setupBottomNavigationView() {
Log.d(TAG, "setupBottomNavigationView: Setting up Bottom Navigation View");
BottomNavigationViewEx bottomNavigationViewEx = (BottomNavigationViewEx) findViewById(R.id.bottom_nav_bar);
BottomNavigationViewHelper.setupBottomNavigationView(bottomNavigationViewEx);
BottomNavigationViewHelper.enableNavigation(mContext, bottomNavigationViewEx);
Menu menu = bottomNavigationViewEx.getMenu();
MenuItem menuItem = menu.getItem(ACTIVITY_NUM);
menuItem.setChecked(true);
}
public void click(View v) {
Intent mIntent = null;
switch (v.getId()) {
case R.id.serve:
mIntent = new Intent(this, SearchActivity.class);
break;
case R.id.imageButton2:
mIntent = new Intent(this, SearchActivity.class);
break;
}
startActivity(mIntent);
}
///////////
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putBoolean(ORIENTATION, mHorizontal);
}
private void setupAdapter() {
List<App> apps = getApps();
SnapAdapter snapAdapter = new SnapAdapter();
if (mHorizontal) {
snapAdapter.addSnap(new Snap(Gravity.CENTER_HORIZONTAL, "Snap Start", apps));
snapAdapter.addSnap(new Snap(Gravity.START, "Snap Middle", apps));
snapAdapter.addSnap(new Snap(Gravity.END, "Snap End", apps));
snapAdapter.addSnap(new Snap(Gravity.CENTER, "Pager snap", apps));
} else {
snapAdapter.addSnap(new Snap(Gravity.CENTER_VERTICAL, "Snap center", apps));
snapAdapter.addSnap(new Snap(Gravity.TOP, "Snap top", apps));
snapAdapter.addSnap(new Snap(Gravity.BOTTOM, "Snap bottom", apps));
}
mRecyclerView.setAdapter(snapAdapter);
}
private List<App> getApps() {
List<App> apps = new ArrayList<>();
apps.add(new App("Google+", "http://uupload.ir/files/aud7_brickone.jpg", 4.6f));
return apps;
}
#Override
public boolean onMenuItemClick(MenuItem item) {
return false;
}
}
SnapAdapter
public class SnapAdapter extends RecyclerView.Adapter<SnapAdapter.ViewHolder> implements GravitySnapHelper.SnapListener {
public static final int VERTICAL = 0;
public static final int HORIZONTAL = 1;
private Context mContext;
private ArrayList<Snap> mSnaps;
// Disable touch detection for parent recyclerView if we use vertical nested recyclerViews
private View.OnTouchListener mTouchListener = new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
v.getParent().requestDisallowInterceptTouchEvent(true);
return false;
}
};
public SnapAdapter() {
mSnaps = new ArrayList<>();
}
public void addSnap(Snap snap) {
mSnaps.add(snap);
}
#Override
public int getItemViewType(int position) {
Snap snap = mSnaps.get(position);
switch (snap.getGravity()) {
case Gravity.CENTER_VERTICAL:
return VERTICAL;
case Gravity.CENTER_HORIZONTAL:
return HORIZONTAL;
case Gravity.START:
return HORIZONTAL;
case Gravity.TOP:
return VERTICAL;
case Gravity.END:
return HORIZONTAL;
case Gravity.BOTTOM:
return VERTICAL;
}
return HORIZONTAL;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = viewType == VERTICAL ? LayoutInflater.from(parent.getContext())
.inflate(R.layout.adapter_snap_vertical, parent, false)
: LayoutInflater.from(parent.getContext())
.inflate(R.layout.adapter_snap, parent, false);
if (viewType == VERTICAL) {
view.findViewById(R.id.recycle_view).setOnTouchListener(mTouchListener);
}
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Snap snap = mSnaps.get(position);
holder.snapTextView.setText(snap.getText());
if (snap.getGravity() == Gravity.START || snap.getGravity() == Gravity.END) {
holder.recyclerView.setLayoutManager(new LinearLayoutManager(holder
.recyclerView.getContext(), LinearLayoutManager.HORIZONTAL, false));
holder.recyclerView.setOnFlingListener(null);
new GravitySnapHelper(snap.getGravity(), false, this).attachToRecyclerView(holder.recyclerView);
} else if (snap.getGravity() == Gravity.CENTER_HORIZONTAL) {
holder.recyclerView.setLayoutManager(new LinearLayoutManager(holder
.recyclerView.getContext(), snap.getGravity() == Gravity.CENTER_HORIZONTAL ?
LinearLayoutManager.HORIZONTAL : LinearLayoutManager.VERTICAL, false));
holder.recyclerView.setOnFlingListener(null);
new LinearSnapHelper().attachToRecyclerView(holder.recyclerView);
} else if (snap.getGravity() == Gravity.CENTER) { // Pager snap
holder.recyclerView.setLayoutManager(new LinearLayoutManager(holder
.recyclerView.getContext(), LinearLayoutManager.HORIZONTAL, false));
holder.recyclerView.setOnFlingListener(null);
new PagerSnapHelper().attachToRecyclerView(holder.recyclerView);
} else { // Top / Bottom
holder.recyclerView.setLayoutManager(new LinearLayoutManager(holder
.recyclerView.getContext()));
holder.recyclerView.setOnFlingListener(null);
new GravitySnapHelper(snap.getGravity()).attachToRecyclerView(holder.recyclerView);
}
holder.recyclerView.setAdapter(new Adapter(mContext, snap.getGravity() == Gravity.START
|| snap.getGravity() == Gravity.END
|| snap.getGravity() == Gravity.CENTER_HORIZONTAL,
snap.getGravity() == Gravity.CENTER, snap.getApps()));
}
#Override
public int getItemCount() {
return mSnaps.size();
}
#Override
public void onSnap(int position) {
Log.d("Snapped: ", position + "");
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public TextView snapTextView;
public RecyclerView recyclerView;
public ViewHolder(View itemView) {
super(itemView);
snapTextView = (TextView) itemView.findViewById(R.id.snapTextView);
recyclerView = (RecyclerView) itemView.findViewById(R.id.recycle_view);
}
}
}
java.lang.IllegalArgumentException: Context must not be null.
A constructor in Java is a block of code similar to a method that's
called when an instance of an object is created.
You should pass Context
private Context mContext;
public Adapter(Context ctx,boolean horizontal, boolean pager, List<App> apps) {
mHorizontal = horizontal;
mApps = apps;
mPager = pager;
this.mContext=ctx; // Call here
}
Logcat Throws
the error is: Error:(110, 40) error: constructor Adapter in class
Adapter cannot be applied to given types; required:
boolean,boolean,List,Context found: boolean,boolean,List
reason: actual and formal argument lists differ in length
Pass Value LIKE
new Adapter(Your_Activity.this, boolean, boolean , List<App>);
Call Adapter like this
Adapter mAdapter = new Adapter (Youractivity_name.this, boolean, boolean , list);
and change the constructor to
public Adapter(Context context ,boolean horizontal, boolean pager, List<App> apps) {
mHorizontal = horizontal;
mApps = apps;
mPager = pager;
mContext = context;
}
I am a beginner in Java, and I downloaded a grid templates for worked in him. I have a very short time and therefore can not learn from all this 0. Please help me with this code, how to create clickable items with new activity what have white pages.
MAIN ACTIVITY
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private AlbumsAdapter adapter;
private List<Album> albumList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
initCollapsingToolbar();
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
albumList = new ArrayList<>();
adapter = new AlbumsAdapter(this, albumList);
RecyclerView.LayoutManager mLayoutManager = new GridLayoutManager(this, 2);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.addItemDecoration(new GridSpacingItemDecoration(2, dpToPx(10), true));
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(adapter);
prepareAlbums();
try {
Glide.with(this).load(R.drawable.bghedb).into((ImageView) findViewById(R.id.backdrop));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Initializing collapsing toolbar
* Will show and hide the toolbar title on scroll
*/
private void initCollapsingToolbar() {
final CollapsingToolbarLayout collapsingToolbar =
(CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
collapsingToolbar.setTitle(" ");
AppBarLayout appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
appBarLayout.setExpanded(true);
// hiding & showing the title when toolbar expanded & collapsed
appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
boolean isShow = false;
int scrollRange = -1;
#Override
public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
if (scrollRange == -1) {
scrollRange = appBarLayout.getTotalScrollRange();
}
if (scrollRange + verticalOffset == 0) {
collapsingToolbar.setTitle(getString(R.string.app_name));
isShow = true;
} else if (isShow) {
collapsingToolbar.setTitle(" ");
isShow = false;
}
}
});
}
/**
* Adding few albums for testing
*/
private void prepareAlbums() {
int[] covers = new int[]{
R.drawable.foto1,
R.drawable.foto2,
R.drawable.foto3,
R.drawable.foto4,
R.drawable.foto5,
R.drawable.foto6,
R.drawable.foto7,
R.drawable.foto8,
R.drawable.foto9,
R.drawable.foto10,
};
Album a = new Album("Start A Blog", 13, covers[0]);
albumList.add(a);
a = new Album("Start A YouTube Channel", 8, covers[1]);
albumList.add(a);
a = new Album("Sell Websites On Flippa", 11, covers[2]);
albumList.add(a);
a = new Album("Join Leapforce", 12, covers[3]);
albumList.add(a);
a = new Album("Use CashPirate App", 14, covers[4]);
albumList.add(a);
a = new Album("Use ReceiptHog App", 1, covers[5]);
albumList.add(a);
a = new Album("Join Micro Job Sites", 11, covers[6]);
albumList.add(a);
a = new Album("Do CPA Marketing", 14, covers[7]);
albumList.add(a);
a = new Album("Start Copywriting", 11, covers[8]);
albumList.add(a);
a = new Album("Develop Mobile Apps", 17, covers[9]);
albumList.add(a);
adapter.notifyDataSetChanged();
}
/**
* RecyclerView item decoration - give equal margin around grid item
*/
public class GridSpacingItemDecoration extends RecyclerView.ItemDecoration {
private int spanCount;
private int spacing;
private boolean includeEdge;
public GridSpacingItemDecoration(int spanCount, int spacing, boolean includeEdge) {
this.spanCount = spanCount;
this.spacing = spacing;
this.includeEdge = includeEdge;
}
#Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view); // item position
int column = position % spanCount; // item column
if (includeEdge) {
outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)
if (position < spanCount) { // top edge
outRect.top = spacing;
}
outRect.bottom = spacing; // item bottom
} else {
outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f / spanCount) * spacing)
if (position >= spanCount) {
outRect.top = spacing; // item top
}
}
}
}
/**
* Converting dp to pixel
*/
private int dpToPx(int dp) {
Resources r = getResources();
return Math.round(TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics()));
}
ALBUM ADAPTER
public class AlbumsAdapter extends RecyclerView.Adapter<AlbumsAdapter.MyViewHolder> {
private Context mContext;
private List<Album> albumList;
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView title, count;
public ImageView thumbnail, overflow;
public MyViewHolder(View view) {
super(view);
title = (TextView) view.findViewById(R.id.title);
count = (TextView) view.findViewById(R.id.count);
thumbnail = (ImageView) view.findViewById(R.id.thumbnail);
overflow = (ImageView) view.findViewById(R.id.overflow);
}
}
public AlbumsAdapter(Context mContext, List<Album> albumList) {
this.mContext = mContext;
this.albumList = albumList;
}
#Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.album_card, parent, false);
return new MyViewHolder(itemView);
}
#Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
Album album = albumList.get(position);
holder.title.setText(album.getName());
// loading album cover using Glide library
Glide.with(mContext).load(album.getThumbnail()).into(holder.thumbnail);
holder.overflow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
}
/**
* Showing popup menu when tapping on 3 dots
*/
#Override
public int getItemCount() {
return albumList.size();
}
ALBUM
public Album(String name, int numOfSongs, int thumbnail) {
this.name = name;
this.numOfSongs = numOfSongs;
this.thumbnail = thumbnail;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getNumOfSongs() {
return numOfSongs;
}
public void setNumOfSongs(int numOfSongs) {
this.numOfSongs = numOfSongs;
}
public int getThumbnail() {
return thumbnail;
}
public void setThumbnail(int thumbnail) {
this.thumbnail = thumbnail;
}
Can someone help me? Do I need to href to each string to new page white, after my problem is any person with free time to care for me to learn from 0 Android? Thank you.t
Simply add these lines
holder.overflow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(context, YourActivity.class).addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
context.startActivity(intent);
}
});
I'm using vertical RecyclerView to list my items and SnapHelper to snap center item. The idea is to randomize selection, so user swipe screen or shake the device and it is scrolling to random position.
Number of items is 20, however I use Integer.MAX_VALUE for the number of elements in RecyclerView and initialize RecyclerView with position Integer.MAX_VALUE / 2 to create some kind of endless list.
To scroll to random position on device shake I need to know current snapped item position.
Is there any way to do it?
Here is my Fragment code:
public class PlaceListFragment extends Fragment {
private static final String TAG = "PlaceListFragment";
public static final String ARG_KEY1 = "key1";
private ArrayList<PlaceItem> places;
private RecyclerView recyclerView;
private SensorManager sensorManager;
private float accelValue;
private float accelLast;
private float shake;
SnapHelper snapHelper;
Vibrator vibe;
public static PlaceListFragment newInstance() {
Bundle args = new Bundle();
PlaceListFragment fragment = new PlaceListFragment();
fragment.setArguments(args);
return fragment;
}
public static PlaceListFragment newInstance(ArrayList<PlaceItem> places) {
Bundle args = new Bundle();
args.putParcelableArrayList(PlaceListActivity.KEY_PLACES, places);
PlaceListFragment fragment = new PlaceListFragment();
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
Log.d(TAG, "onCreate()");
super.onCreate(savedInstanceState);
places = getArguments().getParcelableArrayList(PlaceListActivity.KEY_PLACES);
accelValue = SensorManager.GRAVITY_EARTH;
accelLast = SensorManager.GRAVITY_EARTH;
shake = 0.00f;
vibe = (Vibrator) getActivity().getSystemService(Context.VIBRATOR_SERVICE);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_place_list, container, false);
recyclerView = (RecyclerView) v.findViewById(R.id.place_list);
snapHelper = new LinearSnapHelper();
snapHelper.attachToRecyclerView(recyclerView);
recyclerView.setOnFlingListener(snapHelper);
recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
recyclerView.setAdapter(new PlaceListAdapter(getActivity(), places));
recyclerView.scrollToPosition(PlaceListAdapter.MIDDLE);
sensorManager = (SensorManager) getActivity().getSystemService(Context.SENSOR_SERVICE);
sensorManager.registerListener(sensorListener, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),SensorManager.SENSOR_DELAY_NORMAL);
return v;
}
#Override
public void onResume() {
super.onResume();
}
#Override
public void onPause() {
super.onPause();
}
private final SensorEventListener sensorListener = new SensorEventListener() {
#Override
public void onSensorChanged(SensorEvent event) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
accelLast = accelValue;
accelValue = (float) Math.sqrt((double) (x*x + y*y + z*z));
float delta = accelValue - accelLast;
shake = shake * 0.9f + delta;
if (shake > 12) {
vibe.vibrate(200);
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
};
}
And here is adapter:
public class PlaceListAdapter extends RecyclerView.Adapter<PlaceListAdapter.PlaceAdapterHolder> {
private final FragmentActivity context;
public static final int HALF_MAX_VALUE = Integer.MAX_VALUE/2;
public static int MIDDLE;
private List<PlaceItem> placeItems;
public static class PlaceAdapterHolder extends RecyclerView.ViewHolder {
private ImageView image;
private TextView textMain;
private TextView textRating;
public PlaceAdapterHolder(View itemView) {
super(itemView);
image = (ImageView) itemView.findViewById(R.id.icon);
textMain = (TextView) itemView.findViewById(R.id.txt_main_line);
textRating = (TextView) itemView.findViewById(R.id.txt_right_field);
}
public void bindPlace(PlaceItem placeItem) {
String placeName = placeItem.getName() == null? "?":placeItem.getName();
String firstLetter = placeName.substring(0, 1);
ColorGenerator generator = ColorGenerator.MATERIAL; // or use DEFAULT
int color = generator.getColor(placeName);
TextDrawable drawable = TextDrawable.builder()
.beginConfig()
.toUpperCase()
.endConfig()
.buildRect(firstLetter, color);
image.setImageDrawable(drawable);
textMain.setText(placeItem.getName());
textRating.setText(placeItem.getRating());
}
}
public PlaceListAdapter(FragmentActivity context, List<PlaceItem> placeItems) {
this.context = context;
this.placeItems = placeItems;
MIDDLE = HALF_MAX_VALUE - HALF_MAX_VALUE % placeItems.size();
}
#Override
public PlaceListAdapter.PlaceAdapterHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.place_list_one_line_item, parent, false);
return new PlaceAdapterHolder(view);
}
#Override
public int getItemCount() {
return Integer.MAX_VALUE;
}
#Override
public void onBindViewHolder(PlaceListAdapter.PlaceAdapterHolder holder, final int position) {
final PlaceItem placeItem = getItem(position);
holder.bindPlace(placeItem);
holder.itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
FragmentManager fm = context.getSupportFragmentManager();
PlaceDetailsFragment dialog = PlaceDetailsFragment.newInstance(getItem(position));
dialog.show(fm, "DETAILS_DIALOG");
}
});
}
private PlaceItem getItem(int position)
{
return placeItems.get(position % placeItems.size());
}
}
I used this on a project that had a RecyclerView with SnapHelper, not sure if it is what you want.
mRecyclerView.setHasFixedSize(true);
// use a linear layout manager
mLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
mRecyclerView.setLayoutManager(mLayoutManager);
// specify an adapter (see also next example)
mAdapter = new DemoSlidesAdapter(getApplicationContext());
mRecyclerView.setAdapter(mAdapter);
final SnapHelper snapHelper = new LinearSnapHelper();
snapHelper.attachToRecyclerView(mRecyclerView);
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if(newState == RecyclerView.SCROLL_STATE_IDLE) {
View centerView = snapHelper.findSnapView(mLayoutManager);
int pos = mLayoutManager.getPosition(centerView);
Log.e("Snapped Item Position:",""+pos);
}
}
});
I try to use this code with a PagerSnapHelper to mimic the pager behaviour and it was useful but i found some corner cases to solve, if you move fast from the last page to the first one and keep swapping until see the boundarie then the IDLE state doesnt happen and you lose your index. to solve that I move out the position from the IF and add a extra condition for this corner case.
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
super.onScrollStateChanged(recyclerView, newState)
val centerView = snapHelper.findSnapView(mLayoutManager)
val pos = mLayoutManager.getPosition(centerView!!)
if (newState == RecyclerView.SCROLL_STATE_IDLE || (pos == 0 && newState == RecyclerView.SCROLL_STATE_DRAGGING)) {
Log.d("BINDING", "positionView SCROLL_STATE_IDLE: $pos")
}
}
Code is in kotlin hope it helps
private fun recyclerViewScrollListener() = object: RecyclerView.OnScrollListener() {
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
super.onScrollStateChanged(recyclerView, newState)
if (newState == RecyclerView.SCROLL_STATE_IDLE) {
// layoutManager is LinearLayoutManager
val pos = layoutManager.findFirstCompletelyVisibleItemPosition()
Log.e(TAG, "onScrollStateChanged: $pos")
}
}
}
recyclerView.setOnScrollListener(recyclerViewScrollListener())
recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener(){
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
....
}
})
When I scroll on Recyclerview in my app it closes.
Here is a screenshot:
The main page of app- when i scroll the reyclerview of main page my app was force close:
This is my adapter:
public class RecyclerViewDataAdapter extends RecyclerView.Adapter<RecyclerViewDataAdapter.ItemRowHolder> {
private ArrayList<SectionDataModel> dataList;
private Context mContext;
private ImageView bg;
private boolean isLang;
public RecyclerViewDataAdapter(Context context, ArrayList<SectionDataModel> dataList) {
this.dataList = dataList;
this.mContext = context;
}
#Override
public ItemRowHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_item, null);
ItemRowHolder mh = new ItemRowHolder(v);
return mh;
}
#Override
public void onBindViewHolder(final ItemRowHolder itemRowHolder, int i) {
final String sectionName = dataList.get(i).getHeaderTitle();
final String sectionSub = dataList.get(i).getHeaderSubTitle();
final int sectionhesder = dataList.get(i).getHeader();
final int bgd = dataList.get(i).getPhoto();
final int bgg = dataList.get(i).getBg();
ArrayList singleSectionItems = dataList.get(i).getAllItemsInSection();
itemRowHolder.itemSubTitle.setText(sectionSub);
itemRowHolder.itemTitle.setText(sectionName);
itemRowHolder.bg.setImageResource(bgd);
itemRowHolder.bg.setBackgroundResource(bgg);
if (isLang = Locale.getDefault().getLanguage().equals("fa")) {
itemRowHolder.bg.setScaleType(ImageView.ScaleType.FIT_START);
} else {
itemRowHolder.bg.setScaleType(ImageView.ScaleType.FIT_END);
}
SectionListDataAdapter itemListDataAdapter = new SectionListDataAdapter(mContext, singleSectionItems);
itemRowHolder.recycler_view_list.setHasFixedSize(true);
itemRowHolder.recycler_view_list.setLayoutManager(new LinearLayoutManager(mContext, LinearLayoutManager.HORIZONTAL, false));
itemRowHolder.recycler_view_list.setAdapter(itemListDataAdapter);
itemRowHolder.recycler_view_list.setNestedScrollingEnabled(false);
/* itemRowHolder.recycler_view_list.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
int action = event.getAction();
switch (action) {
case MotionEvent.ACTION_DOWN:
// Disallow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(true);
break;
case MotionEvent.ACTION_UP:
//Allow ScrollView to intercept touch events once again.
v.getParent().requestDisallowInterceptTouchEvent(false);
break;
}
// Handle RecyclerView touch events.
v.onTouchEvent(event);
return true;
}
});*/
itemRowHolder.btnMore.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(mContext, TopicActivity.class);
intent.putExtra("topicn",sectionName.toString());
intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
mContext.startActivity(intent);
}
});
/* Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
}
#Override
public int getItemCount() {
return (null != dataList ? dataList.size() : 0);
}
public class ItemRowHolder extends RecyclerView.ViewHolder {
protected RelativeLayout itemHeader;
protected TextView itemTitle;
protected TextView itemSubTitle;
protected RecyclerView recycler_view_list;
protected Button btnMore;
public ImageView bg;
public ItemRowHolder(View view) {
super(view);
this.itemTitle = (TextView) view.findViewById(R.id.itemTitle);
this.itemSubTitle = (TextView) view.findViewById(R.id.itemsub);
this.itemHeader = (RelativeLayout) view.findViewById(R.id.header);
this.recycler_view_list = (RecyclerView) view.findViewById(R.id.recycler_view_list);
this.btnMore= (Button) view.findViewById(R.id.btnMore);
this.bg= (ImageView) view.findViewById(R.id.bg);
}}}