使用 Serializable - AndroidX 将数据从 RecyclerView 传递到 RecyclerViewMore
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【中文标题】使用 Serializable - AndroidX 将数据从 RecyclerView 传递到 RecyclerViewMore【英文标题】：Pass data from RecyclerView to RecyclerViewMore using Serializable - AndroidX 【发布时间】：2020-02-08 13:17:29 【问题描述】：当我按下“查看所有项目”时，我想在 Fragment 中将 RecyclerView 中的所有项目显示到另一个 Activity 中的 RecyclerViewMore，但是当我想从 RecyclerViewMore 接收数据时我得到 null
//SectionAdapter.java
public class AdapterSectionHotTrendingNews extends RecyclerView.Adapter
private Context mContext;
private ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews;
public AdapterSectionHotTrendingNews(Context mContext, ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews)
this.mContext = mContext;
this.modelSectionHotTrendingNews = modelSectionHotTrendingNews;
@Override
public SectionHotTrendingNewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_section_hottrendingnews, null);
return new SectionHotTrendingNewsViewHolder(v);
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position)
final SectionHotTrendingNewsViewHolder sectionHotTrendingNewsViewHolder = (SectionHotTrendingNewsViewHolder) holder;
ModelSectionHotTrendingNews modelSectionHotTrendingNewsX = modelSectionHotTrendingNews.get(position);
//Set
sectionHotTrendingNewsViewHolder.TVSectionTitle.setText(modelSectionHotTrendingNewsX.getHeaderTitle());
ArrayList singleSectionItems = modelSectionHotTrendingNewsX.getAllItemsInSection();
/*AdapterSingleHotLatestNews.RecyclerViewClickListener listenerLatestNews;
listenerLatestNews = new AdapterSingleHotLatestNews.RecyclerViewClickListener()
@Override
public void onRowHotLatestNewsClick(View view, int position)
@Override
public void onIconHotLatestNewsClick(View view, int position)
;*/
AdapterSingleHotTrendingNews itemListDataAdapter = new AdapterSingleHotTrendingNews(mContext, singleSectionItems);
/*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;
);*/
sectionHotTrendingNewsViewHolder.BTNHotTrendingNewsMore.setOnClickListener(
new View.OnClickListener() @Override public void onClick(View v)
Intent intent = new Intent(mContext, TabMoreHotActivity.class);
new Intent().putExtra("MoreNews", modelSectionHotTrendingNews.get(position).getAllItemsInSection());
mContext.startActivity(intent); );
/*Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
//SetRecyclerView
sectionHotTrendingNewsViewHolder.RecyclerViewSectionHotTrendingNews.setHasFixedSize(true);
sectionHotTrendingNewsViewHolder.RecyclerViewSectionHotTrendingNews.setLayoutManager(new LinearLayoutManager(mContext, LinearLayoutManager.HORIZONTAL, false));
sectionHotTrendingNewsViewHolder.RecyclerViewSectionHotTrendingNews.setAdapter(itemListDataAdapter);
sectionHotTrendingNewsViewHolder.RecyclerViewSectionHotTrendingNews.setNestedScrollingEnabled(false);
@Override
public int getItemCount()
int itemCount = modelSectionHotTrendingNews.size();
return itemCount;
public class SectionHotTrendingNewsViewHolder extends RecyclerView.ViewHolder
protected TextView TVSectionTitle;
protected ImageView BTNHotTrendingNewsMore;
protected RecyclerView RecyclerViewSectionHotTrendingNews;
protected RecyclerView RecyclerViewMoreSectionHotTrendingNews;
public SectionHotTrendingNewsViewHolder(View itemView)
super(itemView);
TVSectionTitle = (TextView) itemView.findViewById(R.id.TV_SectionTitle);
BTNHotTrendingNewsMore= (ImageView) itemView.findViewById(R.id.BTN_HotTrendingNewsMore);
RecyclerViewSectionHotTrendingNews = (RecyclerView) itemView.findViewById(R.id.RecyclerView_Section_HotTrendingNews);
RecyclerViewMoreSectionHotTrendingNews = (RecyclerView) itemView.findViewById(R.id.RecyclerViewMore_Section_HotTrendingNews);
//SingleAdapter.java
public class AdapterSingleHotTrendingNews extends RecyclerView.Adapter
private Context mContext;
private ArrayList<ModelSingleHotTrendingNews> modelSingleHotTrendingNews;
public AdapterSingleHotTrendingNews(Context mContext, ArrayList<ModelSingleHotTrendingNews> modelSingleHotTrendingNews)
this.mContext = mContext;
this.modelSingleHotTrendingNews = modelSingleHotTrendingNews;
//Container
@Override
public SingleHotTrendingNewsViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType)
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item_single_hottrendingnews, null);
return new SingleHotTrendingNewsViewHolder(v);
//Fill Container with Model Setter Getter
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position)
final SingleHotTrendingNewsViewHolder singleHotTrendingNewsViewHolder = (SingleHotTrendingNewsViewHolder) holder;
final ModelSingleHotTrendingNews modelSingleHotTrendingNewsX = modelSingleHotTrendingNews.get(position);
//Set
singleHotTrendingNewsViewHolder.TVGameDate.setText(modelSingleHotTrendingNewsX.getGamedate());
singleHotTrendingNewsViewHolder.TVGameDescription.setText(modelSingleHotTrendingNewsX.getGamedescription());
singleHotTrendingNewsViewHolder.IMGGameImage.setImageResource(modelSingleHotTrendingNewsX.getGameimage());
singleHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
final Boolean booltrendingnewssaving = modelSingleHotTrendingNewsX.getTrendingnewssaving();
final int id = modelSingleHotTrendingNewsX.getId();
if (booltrendingnewssaving == true)
Toast.makeText(v.getContext(), "Turn Off Saved News " + id, Toast.LENGTH_SHORT).show();
singleHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setImageResource(R.drawable.saved_off);
modelSingleHotTrendingNewsX.setTrendingnewssaving(false);
/*updateSavedNewsSaving("update_newssaving", id, false);*/
else if(booltrendingnewssaving == false)
Toast.makeText(v.getContext(), "Turn On Saved News " + id, Toast.LENGTH_SHORT).show();
singleHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setImageResource(R.drawable.saved_on);
modelSingleHotTrendingNewsX.setTrendingnewssaving(true);
/*updateSavedNewsSaving("update_newssaving", id, true);*/
);
/* Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
singleHotTrendingNewsViewHolder.ROWHotTrendingNewsContainer.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
Toast.makeText(v.getContext(), modelSingleHotTrendingNews.get(position).getGamedescription(), Toast.LENGTH_SHORT).show();
//Passing Data to GameDescriptionActivity
Intent intent = new Intent(mContext, GameDetailActivity.class);
intent.putExtra("ImagePKG", modelSingleHotTrendingNews.get(position).getGameimage());
intent.putExtra("NamePKG", modelSingleHotTrendingNews.get(position).getGamedate());
intent.putExtra("UrlPKG", modelSingleHotTrendingNews.get(position).getId());
intent.putExtra("DescriptionPKG", modelSingleHotTrendingNews.get(position).getGamedescription());
mContext.startActivity(intent);
);
@Override
public int getItemCount()
int itemCount = modelSingleHotTrendingNews.size();
return itemCount;
public class SingleHotTrendingNewsViewHolder extends RecyclerView.ViewHolder
TextView TVGameDate;
TextView TVGameDescription;
ImageView IMGGameImage;
ImageView ICONHotTrendingNewsSaving;
private RelativeLayout ROWHotTrendingNewsContainer;
public SingleHotTrendingNewsViewHolder(View itemView)
super(itemView);
TVGameDate = itemView.findViewById(R.id.TV_GameDate);
TVGameDescription = itemView.findViewById(R.id.TV_GameDescription);
IMGGameImage = itemView.findViewById(R.id.IMG_GameImage);
ICONHotTrendingNewsSaving = itemView.findViewById(R.id.ICON_HotTrendingNewsSaving);
ROWHotTrendingNewsContainer = itemView.findViewById(R.id.ROW_HotTrendingNewsContainer);
//ModelSection.java
public class ModelSectionHotTrendingNews implements Serializable
private String headerTitle;
private ArrayList<ModelSingleHotTrendingNews> allItemsInSection;
public ModelSectionHotTrendingNews()
public String getHeaderTitle()
return headerTitle;
public void setHeaderTitle(String headerTitle)
this.headerTitle = headerTitle;
public ArrayList<ModelSingleHotTrendingNews> getAllItemsInSection()
return allItemsInSection;
public void setAllItemsInSection(ArrayList<ModelSingleHotTrendingNews> allItemsInSection)
this.allItemsInSection = allItemsInSection;
//ModelSingle.java
public class ModelSingleHotTrendingNews implements Serializable
private int id;
private String gamedate;
private String gamedescription;
private int gameimage;
private Boolean trendingnewssaving;
private String value;
private String message;
public ModelSingleHotTrendingNews(int id, String gamedate, String gamedescription, int gameimage, Boolean trendingnewssaving, String value, String message)
this.id = id;
this.gamedate = gamedate;
this.gamedescription = gamedescription;
this.gameimage = gameimage;
this.trendingnewssaving = trendingnewssaving;
this.value = value;
this.message = message;
public int getId()
return id;
public void setId(int id)
this.id = id;
public String getGamedate()
return gamedate;
public void setGamedate(String gamedate)
this.gamedate = gamedate;
public String getGamedescription()
return gamedescription;
public void setGamedescription(String gamedescription)
this.gamedescription = gamedescription;
public int getGameimage()
return gameimage;
public void setGameimage(int gameimage)
this.gameimage = gameimage;
public Boolean getTrendingnewssaving()
return trendingnewssaving;
public void setTrendingnewssaving(Boolean trendingnewssaving)
this.trendingnewssaving = trendingnewssaving;
public String getValue()
return value;
public void setValue(String value)
this.value = value;
public String getMessage()
return message;
public void setMessage(String message)
this.message = message;
//This function SectionAdapter.java is to send data from RecyclerView in Fragment to RecyclerViewMore Activity
sectionHotTrendingNewsViewHolder.BTNHotTrendingNewsMore.setOnClickListener(
new View.OnClickListener() @Override public void onClick(View v)
Intent intent = new Intent(mContext, TabMoreHotActivity.class);
new Intent().putExtra("MoreNews", modelSectionHotTrendingNews.get(position).getAllItemsInSection());
mContext.startActivity(intent); );
//我在那些 RecyclerViews 中使用相同的 Model 但不同的 Adapter //我在 Fragment AdapterSection.java,AdapterSingle.java,ModelSection.java,ModelSingle.java中使用RecyclerView //我在Activity中使用RecyclerViewMore AdapterMoreSection.java,AdapterMoreSingle.java,ModelSection.java,ModelSingle.java //RecyclerViewMoreActivity.java
public class TabMoreHotActivity extends AppCompatActivity
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.fragmentmore_tabhot);
AdapterMoreSectionHotTrendingNews adapterMoreSectionHotTrendingNews;
ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews = null;
Bundle bundle = getIntent().getExtras();
if(bundle!=null)
modelSectionHotTrendingNews = (ArrayList<ModelSectionHotTrendingNews>) bundle.getSerializable("MoreNews");
//1
RecyclerView RecyclerViewMoreSingleHotTrendingNews = findViewById(R.id.RecyclerViewMore_Single_HotTrendingNews);
RecyclerViewMoreSingleHotTrendingNews.setHasFixedSize(true);
adapterMoreSectionHotTrendingNews = new AdapterMoreSectionHotTrendingNews(this, modelSectionHotTrendingNews);
RecyclerViewMoreSingleHotTrendingNews.setAdapter(adapterMoreSectionHotTrendingNews);
RecyclerViewMoreSingleHotTrendingNews.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false));
//Optimized
RecyclerViewMoreSingleHotTrendingNews.setHasFixedSize(true);
RecyclerViewMoreSingleHotTrendingNews.setItemViewCacheSize(20);
//我收到了这个错误
E/androidRuntime: FATAL EXCEPTION: main
Process: com.indofun.android.indojoy, PID: 32309
java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference
at com.indofun.android.indojoy.Adapters.AdapterMore_HotTrendingNews.AdapterMoreSectionHotTrendingNews.getItemCount(AdapterMoreSectionHotTrendingNews.java:109)
at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep1(RecyclerView.java:4042)
at androidx.recyclerview.widget.RecyclerView.onMeasure(RecyclerView.java:3532)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:23279)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:715)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:461)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at androidx.appcompat.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:143)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:23279)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6928)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:898)
at android.view.View.measure(View.java:23279)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2873)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1910)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2165)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1779)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7810)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:911)
at android.view.Choreographer.doCallbacks(Choreographer.java:723)
at android.view.Choreographer.doFrame(Choreographer.java:658)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:897)
at android.os.Handler.handleCallback(Handler.java:789)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6938)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
//提供对我有很大帮助的代码
//更新
//AdapterMoreSingle
public class AdapterMoreSingleHotTrendingNews extends RecyclerView.Adapter
private Context mContext;
private ArrayList<ModelSingleHotTrendingNews> modelSingleHotTrendingNews;
public AdapterMoreSingleHotTrendingNews(Context mContext, ArrayList<ModelSingleHotTrendingNews> modelSingleHotTrendingNews)
this.mContext = mContext;
this.modelSingleHotTrendingNews = modelSingleHotTrendingNews;
//Container
@Override
public SingleMoreHotTrendingNewsViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType)
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.itemmore_single_hottrendingnews, null);
return new SingleMoreHotTrendingNewsViewHolder(v);
//Fill Container with Model Setter Getter
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position)
final SingleMoreHotTrendingNewsViewHolder singleMoreHotTrendingNewsViewHolder = (SingleMoreHotTrendingNewsViewHolder) holder;
final ModelSingleHotTrendingNews modelSingleHotTrendingNewsX = modelSingleHotTrendingNews.get(position);
//Set
singleMoreHotTrendingNewsViewHolder.TVGameDate.setText(modelSingleHotTrendingNewsX.getGamedate());
singleMoreHotTrendingNewsViewHolder.TVGameDescription.setText(modelSingleHotTrendingNewsX.getGamedescription());
singleMoreHotTrendingNewsViewHolder.IMGGameImage.setImageResource(modelSingleHotTrendingNewsX.getGameimage());
singleMoreHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
final Boolean booltrendingnewssaving = modelSingleHotTrendingNewsX.getTrendingnewssaving();
final int id = modelSingleHotTrendingNewsX.getId();
if (booltrendingnewssaving == true)
Toast.makeText(v.getContext(), "Turn Off Saved News " + id, Toast.LENGTH_SHORT).show();
singleMoreHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setImageResource(R.drawable.saved_off);
modelSingleHotTrendingNewsX.setTrendingnewssaving(false);
/*updateSavedNewsSaving("update_newssaving", id, false);*/
else if(booltrendingnewssaving == false)
Toast.makeText(v.getContext(), "Turn On Saved News " + id, Toast.LENGTH_SHORT).show();
singleMoreHotTrendingNewsViewHolder.ICONHotTrendingNewsSaving.setImageResource(R.drawable.saved_on);
modelSingleHotTrendingNewsX.setTrendingnewssaving(true);
/*updateSavedNewsSaving("update_newssaving", id, true);*/
);
/* Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
singleMoreHotTrendingNewsViewHolder.ROWHotTrendingNewsContainer.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
Toast.makeText(v.getContext(), modelSingleHotTrendingNews.get(position).getGamedescription(), Toast.LENGTH_SHORT).show();
//Passing Data to GameDescriptionActivity
Intent intent = new Intent(mContext, GameDetailActivity.class);
intent.putExtra("ImagePKG", modelSingleHotTrendingNews.get(position).getGameimage());
intent.putExtra("NamePKG", modelSingleHotTrendingNews.get(position).getGamedate());
intent.putExtra("UrlPKG", modelSingleHotTrendingNews.get(position).getId());
intent.putExtra("DescriptionPKG", modelSingleHotTrendingNews.get(position).getGamedescription());
mContext.startActivity(intent);
);
@Override
public int getItemCount()
int itemCount = modelSingleHotTrendingNews.size();
return itemCount;
public class SingleMoreHotTrendingNewsViewHolder extends RecyclerView.ViewHolder
TextView TVGameDate;
TextView TVGameDescription;
ImageView IMGGameImage;
ImageView ICONHotTrendingNewsSaving;
private RelativeLayout ROWHotTrendingNewsContainer;
public SingleMoreHotTrendingNewsViewHolder(View itemView)
super(itemView);
TVGameDate = itemView.findViewById(R.id.TV_GameDate);
TVGameDescription = itemView.findViewById(R.id.TV_GameDescription);
IMGGameImage = itemView.findViewById(R.id.IMG_GameImage);
ICONHotTrendingNewsSaving = itemView.findViewById(R.id.ICON_HotTrendingNewsSaving);
ROWHotTrendingNewsContainer = itemView.findViewById(R.id.ROW_HotTrendingNewsContainer);
//UPDATED2 AdapterSectionMore.java
public class AdapterMoreSectionHotTrendingNews extends RecyclerView.Adapter
private Context mContext;
private ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews;
public AdapterMoreSectionHotTrendingNews(Context mContext, ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews)
this.mContext = mContext;
this.modelSectionHotTrendingNews = modelSectionHotTrendingNews;
@Override
public SectionMoreHotTrendingNewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.itemmore_section_hottrendingnews, null);
return new SectionMoreHotTrendingNewsViewHolder(v);
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position)
final SectionMoreHotTrendingNewsViewHolder sectionMoreHotTrendingNewsViewHolder = (SectionMoreHotTrendingNewsViewHolder) holder;
ModelSectionHotTrendingNews modelSectionHotTrendingNewsX = modelSectionHotTrendingNews.get(position);
//Set
sectionMoreHotTrendingNewsViewHolder.TVSectionTitle.setText(modelSectionHotTrendingNewsX.getHeaderTitle());
// here you have to change your ArrayList to ArrayList<ModelSingleHotTrendingNews>
ArrayList<ModelSingleHotTrendingNews> singleSectionItems = modelSectionHotTrendingNewsX.getAllItemsInSection();
/*AdapterSingleHotLatestNews.RecyclerViewClickListener listenerLatestNews;
listenerLatestNews = new AdapterSingleHotLatestNews.RecyclerViewClickListener()
@Override
public void onRowHotLatestNewsClick(View view, int position)
@Override
public void onIconHotLatestNewsClick(View view, int position)
;*/
AdapterMoreSingleHotTrendingNews itemListDataAdapter = new AdapterMoreSingleHotTrendingNews(mContext, singleSectionItems);
/*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;
);*/
final String sectionTitle = modelSectionHotTrendingNewsX.getHeaderTitle();
sectionMoreHotTrendingNewsViewHolder.BTNHotTrendingNewsMore.setOnClickListener(
new View.OnClickListener()
@Override public void onClick(View v)
//More IN RecyclerViewMore
);
/*Glide.with(mContext)
.load(feedItem.getImageURL())
.diskCacheStrategy(DiskCacheStrategy.ALL)
.centerCrop()
.error(R.drawable.bg)
.into(feedListRowHolder.thumbView);*/
//SetRecyclerView
sectionMoreHotTrendingNewsViewHolder.RecyclerViewMoreSectionHotTrendingNews.setHasFixedSize(true);
sectionMoreHotTrendingNewsViewHolder.RecyclerViewMoreSectionHotTrendingNews.setLayoutManager(new LinearLayoutManager(mContext, LinearLayoutManager.HORIZONTAL, false));
sectionMoreHotTrendingNewsViewHolder.RecyclerViewMoreSectionHotTrendingNews.setAdapter(itemListDataAdapter);
sectionMoreHotTrendingNewsViewHolder.RecyclerViewMoreSectionHotTrendingNews.setNestedScrollingEnabled(false);
@Override
public int getItemCount()
int itemCount = modelSectionHotTrendingNews.size();
return itemCount;
public class SectionMoreHotTrendingNewsViewHolder extends RecyclerView.ViewHolder
protected TextView TVSectionTitle;
protected ImageView BTNHotTrendingNewsMore;
protected RecyclerView RecyclerViewMoreSectionHotTrendingNews;
public SectionMoreHotTrendingNewsViewHolder(View itemView)
super(itemView);
TVSectionTitle = (TextView) itemView.findViewById(R.id.TV_SectionTitle);
BTNHotTrendingNewsMore= (ImageView) itemView.findViewById(R.id.BTN_HotTrendingNewsMore);
RecyclerViewMoreSectionHotTrendingNews = (RecyclerView) itemView.findViewById(R.id.RecyclerViewMore_Section_HotTrendingNews);
【问题讨论】：
【参考方案1】：因为您将null modelSectionHotTrendingNews 传递给您的适配器。
你只需要在你的TabMoreHotActivityinitialize你的ArrayList
还有一件事你必须在set adapter之前set layout manger到你的recycler view。
public class TabMoreHotActivity extends AppCompatActivity
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.fragmentmore_tabhot);
AdapterMoreSectionHotTrendingNews adapterMoreSectionHotTrendingNews;
// here you have to initialize it
ArrayList<ModelSectionHotTrendingNews> modelSectionHotTrendingNews = new ArrayList<>();
Bundle bundle = getIntent().getExtras();
if(bundle!=null)
modelSectionHotTrendingNews = (ArrayList<ModelSectionHotTrendingNews>) bundle.getSerializable("MoreNews");
//1
RecyclerView RecyclerViewMoreSingleHotTrendingNews = findViewById(R.id.RecyclerViewMore_Single_HotTrendingNews);
RecyclerViewMoreSingleHotTrendingNews.setHasFixedSize(true);
adapterMoreSectionHotTrendingNews = new AdapterMoreSectionHotTrendingNews(this, modelSectionHotTrendingNews);
// here have to set layout manager before set adapter
RecyclerViewMoreSingleHotTrendingNews.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false));
// and then you have to set adapter to recyclerview
RecyclerViewMoreSingleHotTrendingNews.setAdapter(adapterMoreSectionHotTrendingNews);
//Optimized
RecyclerViewMoreSingleHotTrendingNews.setHasFixedSize(true);
RecyclerViewMoreSingleHotTrendingNews.setItemViewCacheSize(20);
更新
将ArrayList 中的onBindViewHolder 中的ArrayList<ModelSingleHotTrendingNews> 更改为AdapterMoreSectionHotTrendingNews 中的ArrayList<ModelSingleHotTrendingNews>。
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position)
final SectionMoreHotTrendingNewsViewHolder sectionMoreHotTrendingNewsViewHolder = (SectionMoreHotTrendingNewsViewHolder) holder;
ModelSectionHotTrendingNews modelSectionHotTrendingNewsX = modelSectionHotTrendingNews.get(position);
//Set
sectionMoreHotTrendingNewsViewHolder.TVSectionTitle.setText(modelSectionHotTrendingNewsX.getHeaderTitle());
// here you have to change your ArrayList to ArrayList<ModelSingleHotTrendingNews>
ArrayList<ModelSingleHotTrendingNews> singleSectionItems = modelSectionHotTrendingNewsX.getAllItemsInSection();
// reset of your codes here.
【讨论】：
我删除了 null 并添加了新的 ArrayList();，哇，谢谢老兄，但是发生错误，告诉我不能使用相同的模型，java.lang.ClassCastException: com.indofun.android.indojoy .Models.Model_HotTrendingNews.ModelSingleHotTrendingNews 不能转换为 com.indofun.android.indojoy.Models.Model_HotTrendingNews.ModelSectionHotTrendingNews at com.indofun.android.indojoy.Adapters.AdapterMore_HotTrendingNews.AdapterMoreSectionHotTrendingNews.onBindViewHolder(AdapterMoreSectionHotTrendingNews.java: .widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:7056) 您的错误清楚地表明您正在将ModelSingleHotTrendingNews 类转换为 ModelSectionHotTrendingNews 在您的 AdapterMoreSectionHotTrendingNews 中。这就是为什么你得到class cast exception
我更新了我上面的问题帖，非常感谢你的帮助
//我再次更新了我上面的帖子（SectionAdapterMore.java），仍然卡在错误中// java.lang.ClassCastException: com.indofun.android.indojoy.Models.Model_HotTrendingNews.ModelSingleHotTrendingNews 无法转换到 com.indofun.android.indojoy.Adapters.AdapterMore_HotTrendingNews.AdapterMoreSectionHotTrendingNews.onBindViewHolder(AdapterMoreSectionHotTrendingNews.java:40) 上的 com.indofun.android.indojoy.Models.Model_HotTrendingNews.ModelSectionHotTrendingNews
确保您从bundle if(bundle!=null) modelSectionHotTrendingNews = (ArrayList<ModelSectionHotTrendingNews>) bundle.getSerializable("MoreNews"); 获得正确的数据以及您从哪个活动调用TabMoreHotActivity？你可以发布它。【参考方案2】：
对于这个错误
java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference
通过@Jakir 的回答，您可以初始化 ArrayList 以使用特定大小（即new ArrayList<>(0);）进行额外点初始化，以减少内存使用量，因为数组列表默认内存中有 10 个对象的大量内存。
或
在 getItem 中检查这个条件
@Override
public int getItemCount()
return modelSectionHotTrendingNews != null && modelSectionHotTrendingNews.size();
它将解决此错误。
用于代码中的可序列化解析
Intent intent = new Intent(mContext, TabMoreHotActivity.class);
// here you create put extra in new intent not the intent that you created
new Intent().putExtra("MoreNews", modelSectionHotTrendingNews.get(position).getAllItemsInSection());
mContext.startActivity(intent);
改成
Intent intent = new Intent(mContext, TabMoreHotActivity.class);
// here you create put extra in new intent not the intent that you created
intent.putExtra("MoreNews", modelSectionHotTrendingNews.get(position).getAllItemsInSection());
mContext.startActivity(intent);
编码愉快.... ;)
【讨论】：
哇，谢谢老兄，但发生错误，告诉我不能使用相同的模型，java.lang.ClassCastException: com.indofun.android.indojoy.Models.Model_HotTrendingNews.ModelSingleHotTrendingNews 不能转换为 com.indofun。 android.indojoy.Models.Model_HotTrendingNews.ModelSectionHotTrendingNews at com.indofun.android.indojoy.Adapters.AdapterMore_HotTrendingNews.AdapterMoreSectionHotTrendingNews.onBindViewHolder(AdapterMoreSectionHotTrendingNews.java:40) at androidx.recyclerview.widget.RecyclerView$Adapter.onBindViewHolder(Recycler.onBindViewHolder )以上是关于使用 Serializable - AndroidX 将数据从 RecyclerView 传递到 RecyclerViewMore的主要内容，如果未能解决你的问题，请参考以下文章
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