我正在使用RecylerView创建一个应用程序，其中填充了来自在线服务器的数据。它有一个带有收藏夹按钮的自定义布局，单击该图标时会发生更改。我在使用RecyclerView时尝试保存所选视图的状态时出现问题。 RecyclerView不会在滚动备份时保存选定的状态。请帮助。
模型类
package com.smartdevelopers.kandie.nicedrawer.newsModel;
/**
* Created by 4331 on 25/09/2015.
*/
public class Latest {
public String excerpt;
public String articleImage;
public String articleUrl;
public boolean mfavourite;
public boolean isFavourite(){
return mfavourite;
}
public String getArticleUrl() {
return articleUrl;
}
public void setArticleUrl(String articleUrl) {
this.articleUrl = articleUrl;
}
public String getExcerpt() {
return excerpt;
}
public void setExcerpt(String excerpt) {
this.excerpt = excerpt;
}
public String getArticleImage() {
return articleImage;
}
public void setArticleImage(String articleImage) {
this.articleImage = articleImage;
}
}
适配器
package com.smartdevelopers.kandie.nicedrawer.newsAdapter;
import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.support.v7.widget.RecyclerView;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import com.nispok.snackbar.Snackbar;
import com.nispok.snackbar.SnackbarManager;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.smartdevelopers.kandie.nicedrawer.R;
import com.smartdevelopers.kandie.nicedrawer.ReadArticleActivity;
import com.smartdevelopers.kandie.nicedrawer.newsModel.Latest;
import com.smartdevelopers.kandie.nicedrawer.util.SharedPreferenceRecycler;
import java.util.HashMap;
import java.util.List;
/**
* Created by 4331 on 29/09/2015.
*/
public class OtherNewsAdapter extends RecyclerView.Adapter<OtherNewsAdapter.ViewHolder> {
private List<Latest> feedItemList;
private Context mContext;
private static final String TAG = "ActivityGplus";
SharedPreferenceRecycler sharedPreference = new SharedPreferenceRecycler();
public OtherNewsAdapter(Context context, List<Latest> feedItemList) {
this.feedItemList = feedItemList;
this.mContext = context;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row_other_news, null);
ViewHolder mh = new ViewHolder(v);
return mh;
}
@Override
public void onBindViewHolder(final ViewHolder viewHolder, int i) {
final Latest feedItem = feedItemList.get(i);
ImageLoader imageLoader = ImageLoader.getInstance();
DisplayImageOptions options = new DisplayImageOptions.Builder().cacheInMemory(true)
.cacheOnDisc(true).resetViewBeforeLoading(true)
.showImageForEmptyUri(R.drawable.placeholder)
.showImageOnFail(R.drawable.placeholder)
.showImageOnLoading(R.drawable.placeholder).build();
//download and display image from url
imageLoader.displayImage(feedItem.getArticleImage(), viewHolder.thumbnail, options);
// Glide.with(mContext).load(feedItem.getArticleImage())
// .error(R.drawable.placeholder)
// .placeholder(R.drawable.placeholder)
// .into(viewHolder.thumbnail);
viewHolder.title.setText(Html.fromHtml(feedItem.getExcerpt()));
viewHolder.articleUrl.setText(Html.fromHtml(feedItem.getArticleUrl()));
viewHolder.title.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(mContext, ReadArticleActivity.class);
intent.putExtra("articleUrl", viewHolder.articleUrl.getText().toString());
mContext.startActivity(intent);
}
});
/*If a product exists in shared preferences then set heart_red drawable
* and set a tag*/
if (checkFavoriteItem(feedItem)) {
viewHolder.favImage.setImageResource(R.drawable.heart_red);
viewHolder.favImage.setSelected(true);
viewHolder.favImage.setTag("red");
hashMap.get(i);
}
else {
viewHolder.favImage.setImageResource(R.drawable.heart_grey);
viewHolder.favImage.setSelected(false);
viewHolder.favImage.setTag("grey");
}
viewHolder.title.setTag(viewHolder);
viewHolder.thumbnail.setId(R.id.otherImage);
viewHolder.articleUrl.setTag(viewHolder);
}
@Override
public int getItemCount() {
return (null != feedItemList ? feedItemList.size() : 0);
}
@Override
public long getItemId(int position) {
return super.getItemId(position);
}
View.OnClickListener clickListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
OtherNewsRowHolder holder = (OtherNewsRowHolder) view.getTag();
int position = holder.getPosition();
Latest feedItem = feedItemList.get(position);
Toast.makeText(mContext, feedItem.getExcerpt(), Toast.LENGTH_SHORT).show();
}
};
/*Checks whether a particular product exists in SharedPreferences*/
public boolean checkFavoriteItem(Latest checkProduct) {
boolean check = false;
List<Latest> favorites = sharedPreference.getFavorites(mContext);
if (favorites != null) {
for (Latest product : favorites) {
if (product.equals(checkProduct)) {
check = true;
break;
}
}
}
return check;
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
protected ImageView thumbnail, favImage;
protected TextView title,articleUrl;
public ViewHolder(View itemView) {
super(itemView);
this.thumbnail = (ImageView) itemView.findViewById(R.id.otherImage);
this.title = (TextView) itemView.findViewById(R.id.otherExcerpt);
this.articleUrl=(TextView)itemView.findViewById(R.id.otherUrl);
this.favImage = (ImageView) itemView.findViewById(R.id.imgbtn_favorite);
favImage.setOnClickListener(this);
}
@Override
public void onClick(View v) {
String tag = favImage.getTag().toString();
if(!favImage.isSelected()) {
if (tag.equalsIgnoreCase("grey")) {
sharedPreference.addFavorite(mContext, feedItemList.get(getItemCount() - 1));
// Toast.makeText(mContext, mContext.getResources().getString(R.string.add_favr),
// Toast.LENGTH_SHORT).show();
//SnackBack
SnackbarManager.show(
Snackbar.with(mContext)
.text(R.string.add_favr)
.textColor(Color.WHITE)
.color(Color.RED)
.duration(Snackbar.SnackbarDuration.LENGTH_SHORT));
//End of SnackBack
favImage.setTag("red");
favImage.setImageResource(R.drawable.heart_red);
}
}
else {
sharedPreference.removeFavorite(mContext, feedItemList.get(getItemCount() - 1));
favImage.setTag("grey");
favImage.setImageResource(R.drawable.heart_grey);
//SnackBack
SnackbarManager.show(
Snackbar.with(mContext)
.text(R.string.remove_favr)
.textColor(Color.WHITE)
.color(Color.RED) .duration(Snackbar.SnackbarDuration.LENGTH_SHORT).animation(false));
//End of SnackBack
}
}
}
}
答案 0 :(得分：0)
我几天前遇到过这个问题 - 原因是你没有用适用的更改更新你的feedItemList。如果您通过设置Latest类的一些成员变量（如setExcerpt（））更新列表，那么您的recyclerview将正常工作。