Textview 未显示在 Recycler View 的卡片视图中
Textview not displaying in the card view of Recycler View
我想在回收站视图的文本视图中显示一串名称。这一步的.xml在下面
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:id="@+id/youtube_row_card_view"
android:layout_height="120dp"
android:layout_marginLeft="1dp"
android:layout_marginStart="1dp"
android:layout_marginTop="0dp"
android:layout_marginBottom="0dp"
app:cardCornerRadius="10dp"
app:contentPadding="4dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.youtube.player.YouTubeThumbnailView
android:id="@+id/video_thumbnail_image_view"
android:layout_width="140dp"
android:layout_height="90dp"
android:contentDescription="@string/thumbnail_image_view_desc"
android:scaleType="centerCrop" ></com.google.android.youtube.player.YouTubeThumbnailView>
<TextView
android:id="@+id/icon_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:textColor="@android:color/black"></TextView>
</LinearLayout>
</androidx.cardview.widget.CardView>
适配器class自定义适配器在下方
package com.CurrentMediaPakLiveNews;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.viewHolder> {
Context context;
ArrayList<itemModel> items;
public class viewHolder extends RecyclerView.ViewHolder {
public TextView iconName;
public viewHolder(View itemView) {
super(itemView);
this.iconName = itemView.findViewById(R.id.icon_name);
}
}
public CustomAdapter(Context context, ArrayList<itemModel> items) {
this.context = context;
this.items = items;
}
@Override
public viewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.youtube_video_custom_layout, parent, false);
viewHolder viewHolder = new viewHolder(view);
return viewHolder;
}
@Override
public void onBindViewHolder(viewHolder holder, int position) {
TextView iconName =holder.iconName;
holder.iconName.setText(items.get(position).getName());
}
@Override
public int getItemCount() {
return items.size();
}
}
而 itemModel class 声明为：
package com.CurrentMediaPakLiveNews;
public class itemModel {
String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
textview 的 MainActivity 声明如下：
import android.util.Log;
import android.view.View;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.DefaultItemAnimator;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.ads.MobileAds;
import com.google.android.gms.ads.initialization.InitializationStatus;
import com.google.android.gms.ads.initialization.OnInitializationCompleteListener;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayerSupportFragmentX;
import java.util.ArrayList;
import java.util.Collections;
import adapter.SecondYoutubeVideoAdapter;
import adapter.YoutubeVideoAdapter;
import utils.Constants;
import utils.RecyclerViewOnClickListener;
import utils.RecyclerViewOnClickListener2;
public class MainActivity extends AppCompatActivity {
private AdView mAdView;
private AdView mAdView2;
//custom adapter
private static final String TAG = MainActivity.class.getSimpleName();
private RecyclerView firstrecyclerView;
private RecyclerView secondrecyclerView;
ArrayList<itemModel> items;
String[] iconName = {"GEo","Ary","Sama","Hum","dawn","gnn","aj","92","news1","neo"};
//youtube player fragment
private YouTubePlayerSupportFragmentX youTubePlayerFragment;
private ArrayList<String> youtubeVideoArrayList;
private ArrayList<String> secondyoutubeVideoArrayList;
//youtube player to play video when new video selected
private YouTubePlayer youTubePlayer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
generateDummyVideoList();
initializeYoutubePlayer();
setUpRecyclerView();
populateRecyclerView();
private void setUpRecyclerView() {
firstrecyclerView = findViewById(R.id.first_recycler_view);
firstrecyclerView.setHasFixedSize(true);
items = new ArrayList<>();
//Horizontal direction recycler view
LinearLayoutManager firstlinearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
firstrecyclerView.setLayoutManager(firstlinearLayoutManager);
firstrecyclerView.setItemAnimator(new DefaultItemAnimator());
for (int i = 0; i < iconName.length; i++) {
itemModel itemModel = new itemModel();
itemModel.setName(iconName[i]);
items.add(itemModel);
}
private void populateRecyclerView() {
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
final YoutubeVideoAdapter adapter = new YoutubeVideoAdapter(this, youtubeVideoArrayList);
firstrecyclerView.setAdapter(adapter);
输出显示除 TEXTVIEW 之外的所有内容。没有显示列表。我已经在 Whosebug 上尝试了关于依赖项、class 导入等的 ecery 解决方案，但找不到任何解决方案。请有人帮助我，因为我不是普通开发人员，而是自学者。
我的YoutubeVideoAdapter.java低于
package adapter;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.RecyclerView;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubeThumbnailLoader;
import com.google.android.youtube.player.YouTubeThumbnailView;
import com.CurrentMediaPakLiveNews.R;
import java.util.ArrayList;
import holder.YoutubeViewHolder;
import utils.Constants;
/**
* Created by sonu on 10/11/17.
*/
public class YoutubeVideoAdapter extends RecyclerView.Adapter<YoutubeViewHolder> {
private static final String TAG = YoutubeVideoAdapter.class.getSimpleName();
private Context context;
private ArrayList<String> youtubeVideoModelArrayList;
//position to check which position is selected
private int selectedPosition = 0;
public YoutubeVideoAdapter(Context context, ArrayList<String> youtubeVideoModelArrayList) {
this.context = context;
this.youtubeVideoModelArrayList = youtubeVideoModelArrayList;
}
@Override
public YoutubeViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
View view = layoutInflater.inflate(R.layout.youtube_video_custom_layout, parent, false);
return new YoutubeViewHolder(view);
}
@Override
public void onBindViewHolder(YoutubeViewHolder holder, final int position) {
//if selected position is equal to that mean view is selected so change the cardview color
if (selectedPosition == position) {
holder.youtubeCardView.setCardBackgroundColor(ContextCompat.getColor(context, R.color.colorPrimary));
} else {
//if selected position is not equal to that mean view is not selected so change the cardview color to white back again
holder.youtubeCardView.setCardBackgroundColor(ContextCompat.getColor(context, android.R.color.white));
}
/* initialize the thumbnail image view , we need to pass Developer Key */
holder.videoThumbnailImageView.initialize(Constants.DEVELOPER_KEY, new YouTubeThumbnailView.OnInitializedListener() {
@Override
public void onInitializationSuccess(YouTubeThumbnailView youTubeThumbnailView, final YouTubeThumbnailLoader youTubeThumbnailLoader) {
//when initialization is sucess, set the video id to thumbnail to load
youTubeThumbnailLoader.setVideo(youtubeVideoModelArrayList.get(position));
youTubeThumbnailLoader.setOnThumbnailLoadedListener(new YouTubeThumbnailLoader.OnThumbnailLoadedListener() {
@Override
public void onThumbnailLoaded(YouTubeThumbnailView youTubeThumbnailView, String s) {
//when thumbnail loaded successfully release the thumbnail loader as we are showing thumbnail in adapter
youTubeThumbnailLoader.release();
}
@Override
public void onThumbnailError(YouTubeThumbnailView youTubeThumbnailView, YouTubeThumbnailLoader.ErrorReason errorReason) {
//print or show error when thumbnail load failed
Log.e(TAG, "Youtube Thumbnail Error");
}
});
}
@Override
public void onInitializationFailure(YouTubeThumbnailView youTubeThumbnailView, YouTubeInitializationResult youTubeInitializationResult) {
//print or show error when initialization failed
Log.e(TAG, "Youtube Initialization Failure");
}
});
}
@Override
public int getItemCount() {
return youtubeVideoModelArrayList != null ? youtubeVideoModelArrayList.size() : 0;
}
/**
* method the change the selected position when item clicked
* @param selectedPosition
*/
public void setSelectedPosition(int selectedPosition) {
this.selectedPosition = selectedPosition;
//when item selected notify the adapter
notifyDataSetChanged();
}
}
您正在将不同的适配器应用到同一个 recyclerview，这意味着最后一个可见的将是最后一个。
你可以在这里看到：
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
final YoutubeVideoAdapter adapter = new YoutubeVideoAdapter(this, youtubeVideoArrayList);
firstrecyclerView.setAdapter(adapter);
如果您注意到，您正在 firstrecyclerView.setAdapter(adapterf) 附加 CustomAdapter。然后，您再次 firstrecyclerView.setAdapter(adapter) 附加 YoutubeVideoAdapter。只有最后一个适配器会发生，因为它会覆盖前一个。
编辑：
据我了解，您想渲染一个视图，在其中显示 YoutubeThumbnail 和该缩略图下方的 TextView。在您的 CustomAdapter 中，您正在使用 itemModel 的列表。考虑向保存 Youtube 视频 URL 的 itemModel 添加一个属性。如果你这样做，你可以同时显示缩略图和 TextView，你只需要将你的 CustomAdapter 修改为与你的 YoutubeVideoAdapter 相同。
即：
您的 ItemModel 将如下所示：
public class itemModel {
String name;
String youtubeUrl;
public itemoModel(String name, String youtubeUrl){
this.name = name;
this.youtubeUrl = youtubeUrl;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getYoutubeUrl(){
return this.youtubeUrl;
}
public void setYoutubeUrl(String youtubeUrl){
this.youtubeUrl = youtubeUrl;
}
}
你的 CustomAdapter：
public class viewHolder extends RecyclerView.ViewHolder {
public TextView iconName;
public YouTubeThumbnailView thumbnail;
public viewHolder(View itemView) {
super(itemView);
this.iconName = itemView.findViewById(R.id.icon_name);
this.thumbnail = itemView.findViewById(R.id.video_thumbnail_image_view);
}
}
@Override
public void onBindViewHolder(viewHolder holder, int position) {
TextView iconName =holder.iconName;
holder.iconName.setText(items.get(position).getName());
YouTubeThumbnailView thumbnail = holder.thumbnail;
String youtubeUrl = items.get(position).getYoutubeUrl();
//Do what you need to do with the youtubeUrl
}
这样你只需要使用一个适配器和一个 recyclerView 以及你已经在此处完成的代码：
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
如果对您有帮助，请告诉我！
我想在回收站视图的文本视图中显示一串名称。这一步的.xml在下面
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:id="@+id/youtube_row_card_view"
android:layout_height="120dp"
android:layout_marginLeft="1dp"
android:layout_marginStart="1dp"
android:layout_marginTop="0dp"
android:layout_marginBottom="0dp"
app:cardCornerRadius="10dp"
app:contentPadding="4dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.youtube.player.YouTubeThumbnailView
android:id="@+id/video_thumbnail_image_view"
android:layout_width="140dp"
android:layout_height="90dp"
android:contentDescription="@string/thumbnail_image_view_desc"
android:scaleType="centerCrop" ></com.google.android.youtube.player.YouTubeThumbnailView>
<TextView
android:id="@+id/icon_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:textColor="@android:color/black"></TextView>
</LinearLayout>
</androidx.cardview.widget.CardView>
适配器class自定义适配器在下方
package com.CurrentMediaPakLiveNews;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.viewHolder> {
Context context;
ArrayList<itemModel> items;
public class viewHolder extends RecyclerView.ViewHolder {
public TextView iconName;
public viewHolder(View itemView) {
super(itemView);
this.iconName = itemView.findViewById(R.id.icon_name);
}
}
public CustomAdapter(Context context, ArrayList<itemModel> items) {
this.context = context;
this.items = items;
}
@Override
public viewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(context).inflate(R.layout.youtube_video_custom_layout, parent, false);
viewHolder viewHolder = new viewHolder(view);
return viewHolder;
}
@Override
public void onBindViewHolder(viewHolder holder, int position) {
TextView iconName =holder.iconName;
holder.iconName.setText(items.get(position).getName());
}
@Override
public int getItemCount() {
return items.size();
}
}
而 itemModel class 声明为：
package com.CurrentMediaPakLiveNews;
public class itemModel {
String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
textview 的 MainActivity 声明如下：
import android.util.Log;
import android.view.View;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.DefaultItemAnimator;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.ads.MobileAds;
import com.google.android.gms.ads.initialization.InitializationStatus;
import com.google.android.gms.ads.initialization.OnInitializationCompleteListener;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayerSupportFragmentX;
import java.util.ArrayList;
import java.util.Collections;
import adapter.SecondYoutubeVideoAdapter;
import adapter.YoutubeVideoAdapter;
import utils.Constants;
import utils.RecyclerViewOnClickListener;
import utils.RecyclerViewOnClickListener2;
public class MainActivity extends AppCompatActivity {
private AdView mAdView;
private AdView mAdView2;
//custom adapter
private static final String TAG = MainActivity.class.getSimpleName();
private RecyclerView firstrecyclerView;
private RecyclerView secondrecyclerView;
ArrayList<itemModel> items;
String[] iconName = {"GEo","Ary","Sama","Hum","dawn","gnn","aj","92","news1","neo"};
//youtube player fragment
private YouTubePlayerSupportFragmentX youTubePlayerFragment;
private ArrayList<String> youtubeVideoArrayList;
private ArrayList<String> secondyoutubeVideoArrayList;
//youtube player to play video when new video selected
private YouTubePlayer youTubePlayer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
generateDummyVideoList();
initializeYoutubePlayer();
setUpRecyclerView();
populateRecyclerView();
private void setUpRecyclerView() {
firstrecyclerView = findViewById(R.id.first_recycler_view);
firstrecyclerView.setHasFixedSize(true);
items = new ArrayList<>();
//Horizontal direction recycler view
LinearLayoutManager firstlinearLayoutManager = new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
firstrecyclerView.setLayoutManager(firstlinearLayoutManager);
firstrecyclerView.setItemAnimator(new DefaultItemAnimator());
for (int i = 0; i < iconName.length; i++) {
itemModel itemModel = new itemModel();
itemModel.setName(iconName[i]);
items.add(itemModel);
}
private void populateRecyclerView() {
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
final YoutubeVideoAdapter adapter = new YoutubeVideoAdapter(this, youtubeVideoArrayList);
firstrecyclerView.setAdapter(adapter);
输出显示除 TEXTVIEW 之外的所有内容。没有显示列表。我已经在 Whosebug 上尝试了关于依赖项、class 导入等的 ecery 解决方案，但找不到任何解决方案。请有人帮助我，因为我不是普通开发人员，而是自学者。
我的YoutubeVideoAdapter.java低于
package adapter;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.RecyclerView;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubeThumbnailLoader;
import com.google.android.youtube.player.YouTubeThumbnailView;
import com.CurrentMediaPakLiveNews.R;
import java.util.ArrayList;
import holder.YoutubeViewHolder;
import utils.Constants;
/**
* Created by sonu on 10/11/17.
*/
public class YoutubeVideoAdapter extends RecyclerView.Adapter<YoutubeViewHolder> {
private static final String TAG = YoutubeVideoAdapter.class.getSimpleName();
private Context context;
private ArrayList<String> youtubeVideoModelArrayList;
//position to check which position is selected
private int selectedPosition = 0;
public YoutubeVideoAdapter(Context context, ArrayList<String> youtubeVideoModelArrayList) {
this.context = context;
this.youtubeVideoModelArrayList = youtubeVideoModelArrayList;
}
@Override
public YoutubeViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
View view = layoutInflater.inflate(R.layout.youtube_video_custom_layout, parent, false);
return new YoutubeViewHolder(view);
}
@Override
public void onBindViewHolder(YoutubeViewHolder holder, final int position) {
//if selected position is equal to that mean view is selected so change the cardview color
if (selectedPosition == position) {
holder.youtubeCardView.setCardBackgroundColor(ContextCompat.getColor(context, R.color.colorPrimary));
} else {
//if selected position is not equal to that mean view is not selected so change the cardview color to white back again
holder.youtubeCardView.setCardBackgroundColor(ContextCompat.getColor(context, android.R.color.white));
}
/* initialize the thumbnail image view , we need to pass Developer Key */
holder.videoThumbnailImageView.initialize(Constants.DEVELOPER_KEY, new YouTubeThumbnailView.OnInitializedListener() {
@Override
public void onInitializationSuccess(YouTubeThumbnailView youTubeThumbnailView, final YouTubeThumbnailLoader youTubeThumbnailLoader) {
//when initialization is sucess, set the video id to thumbnail to load
youTubeThumbnailLoader.setVideo(youtubeVideoModelArrayList.get(position));
youTubeThumbnailLoader.setOnThumbnailLoadedListener(new YouTubeThumbnailLoader.OnThumbnailLoadedListener() {
@Override
public void onThumbnailLoaded(YouTubeThumbnailView youTubeThumbnailView, String s) {
//when thumbnail loaded successfully release the thumbnail loader as we are showing thumbnail in adapter
youTubeThumbnailLoader.release();
}
@Override
public void onThumbnailError(YouTubeThumbnailView youTubeThumbnailView, YouTubeThumbnailLoader.ErrorReason errorReason) {
//print or show error when thumbnail load failed
Log.e(TAG, "Youtube Thumbnail Error");
}
});
}
@Override
public void onInitializationFailure(YouTubeThumbnailView youTubeThumbnailView, YouTubeInitializationResult youTubeInitializationResult) {
//print or show error when initialization failed
Log.e(TAG, "Youtube Initialization Failure");
}
});
}
@Override
public int getItemCount() {
return youtubeVideoModelArrayList != null ? youtubeVideoModelArrayList.size() : 0;
}
/**
* method the change the selected position when item clicked
* @param selectedPosition
*/
public void setSelectedPosition(int selectedPosition) {
this.selectedPosition = selectedPosition;
//when item selected notify the adapter
notifyDataSetChanged();
}
}
您正在将不同的适配器应用到同一个 recyclerview，这意味着最后一个可见的将是最后一个。
你可以在这里看到：
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
final YoutubeVideoAdapter adapter = new YoutubeVideoAdapter(this, youtubeVideoArrayList);
firstrecyclerView.setAdapter(adapter);
如果您注意到，您正在 firstrecyclerView.setAdapter(adapterf) 附加 CustomAdapter。然后，您再次 firstrecyclerView.setAdapter(adapter) 附加 YoutubeVideoAdapter。只有最后一个适配器会发生，因为它会覆盖前一个。
编辑：
据我了解，您想渲染一个视图，在其中显示 YoutubeThumbnail 和该缩略图下方的 TextView。在您的 CustomAdapter 中，您正在使用 itemModel 的列表。考虑向保存 Youtube 视频 URL 的 itemModel 添加一个属性。如果你这样做，你可以同时显示缩略图和 TextView，你只需要将你的 CustomAdapter 修改为与你的 YoutubeVideoAdapter 相同。
即：
您的 ItemModel 将如下所示：
public class itemModel {
String name;
String youtubeUrl;
public itemoModel(String name, String youtubeUrl){
this.name = name;
this.youtubeUrl = youtubeUrl;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getYoutubeUrl(){
return this.youtubeUrl;
}
public void setYoutubeUrl(String youtubeUrl){
this.youtubeUrl = youtubeUrl;
}
}
你的 CustomAdapter：
public class viewHolder extends RecyclerView.ViewHolder {
public TextView iconName;
public YouTubeThumbnailView thumbnail;
public viewHolder(View itemView) {
super(itemView);
this.iconName = itemView.findViewById(R.id.icon_name);
this.thumbnail = itemView.findViewById(R.id.video_thumbnail_image_view);
}
}
@Override
public void onBindViewHolder(viewHolder holder, int position) {
TextView iconName =holder.iconName;
holder.iconName.setText(items.get(position).getName());
YouTubeThumbnailView thumbnail = holder.thumbnail;
String youtubeUrl = items.get(position).getYoutubeUrl();
//Do what you need to do with the youtubeUrl
}
这样你只需要使用一个适配器和一个 recyclerView 以及你已经在此处完成的代码：
CustomAdapter adapterf = new CustomAdapter(this, items);
firstrecyclerView.setAdapter(adapterf);
如果对您有帮助，请告诉我！