java - E/RecyclerView:没有附加适配器;跳过布局(需要帮助)
问题描述
我正在构建一个连接到我的 Drupal API 的应用程序。不知何故,我的应用程序中没有显示任何数据。我在代码中没有看到任何错误,并且在线调试给出了以下错误: E/RecyclerView: No adapter attach; 跳过布局
这是我的 MainActivity 代码:
package com.example.eindopdrachtcmsapi;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.content.Intent;
import android.os.Bundle;
import android.text.TextWatcher;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.TextView;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonArrayRequest;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.security.PrivateKey;
import java.util.ArrayList;
import java.util.LinkedList;
public class MainActivity extends AppCompatActivity implements ExampleAdapter.onItemClickListener {
public static final String EXTRA_TITLE = "title";
public static final String EXTRA_BODY = "body";
public static final String EXTRA_LINK = "link";
private RecyclerView mRecyclerView;
private ExampleAdapter mExampleAdapter;
private ArrayList<ExampleItem> mExampleList;
private RequestQueue mRequestQueue;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = findViewById(R.id.recycler_view);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setAdapter(mExampleAdapter);
mExampleList = new ArrayList<>();
mRequestQueue = Volley.newRequestQueue(this);
parseJSON();
}
private void parseJSON() {
String url = "http://vistudio.be/api/portfolio";
JsonArrayRequest request = new JsonArrayRequest(Request.Method.GET, url, null,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
try {
for (int i = 0; i < response.length(); i++) {
JSONObject portfolio = response.getJSONObject(i);
String title = portfolio.getString("title");
String body = portfolio.getString("body");
String link = portfolio.getString("field_website_url");
mExampleList.add(new ExampleItem(title, body, link));
}
mExampleAdapter = new ExampleAdapter(MainActivity.this, mExampleList);
mRecyclerView.setAdapter(mExampleAdapter);
mExampleAdapter.setOnClickListener(MainActivity.this, new ExampleAdapter.onItemClickListener() {
@Override
public void onItemClick(int position) {
ExampleItem clickedItem = mExampleList.get(position);
String title = clickedItem.getTitle();
String Link = clickedItem.getLink();
Intent mSharingIntent = new Intent(Intent.ACTION_SEND);
mSharingIntent.setType("text/plain");
mSharingIntent.putExtra(Intent.EXTRA_SUBJECT, "Vistudio");
mSharingIntent.putExtra(Intent.EXTRA_TEXT, title + " - "+ Link);
startActivity(Intent.createChooser(mSharingIntent, "Share"));
}
});
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
mRequestQueue.add(request);
}
@Override
public void onItemClick(int position) {
Intent detailIntent = new Intent(this, DetailActivity.class);
ExampleItem clickedItem = mExampleList.get(position);
detailIntent.putExtra(EXTRA_TITLE, clickedItem.getTitle());
detailIntent.putExtra(EXTRA_BODY, clickedItem.getBody());
detailIntent.putExtra(EXTRA_LINK, clickedItem.getLink());
mExampleAdapter.setOnClickListener(MainActivity.this, new ExampleAdapter.onItemClickListener() {
@Override
public void onItemClick(int position) {
ExampleItem clickedItem = mExampleList.get(position);
String title = clickedItem.getTitle();
String Link = clickedItem.getLink();
Intent mSharingIntent = new Intent(Intent.ACTION_SEND);
mSharingIntent.setType("text/plain");
mSharingIntent.putExtra(Intent.EXTRA_SUBJECT, "Vistudio");
mSharingIntent.putExtra(Intent.EXTRA_TEXT, title + " - "+ Link);
startActivity(Intent.createChooser(mSharingIntent, "Share"));
}
});
startActivity(detailIntent);
}
}
我的适配器代码:
package com.example.eindopdrachtcmsapi;
import android.content.Context;
import android.graphics.PorterDuffColorFilter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.portfolioViewHolder>{
private Context mContext;
private ArrayList<ExampleItem> mExampleList;
private onItemClickListener mListener;
private onItemClickListener mListenerShare;
public interface onItemClickListener{
void onItemClick(int position);
}
public void setOnClickListener(onItemClickListener listener, onItemClickListener listenerShare){
mListener = listener;
mListenerShare = listenerShare;
}
public ExampleAdapter(Context context, ArrayList<ExampleItem> ExampleList) {
mContext = context;
mExampleList = ExampleList;
}
@Override
public portfolioViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.exampleitem, parent, false);
return new portfolioViewHolder(v);
}
@Override
public void onBindViewHolder(portfolioViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
String title = currentItem.getTitle();
String body = currentItem.getBody();
String link = currentItem.getLink();
holder.mTextViewTitle.setText(title);
holder.mTextViewBody.setText(body);
holder.mTextViewLink.setText(link);
}
@Override
public int getItemCount() {
return mExampleList.size();
}
public class portfolioViewHolder extends RecyclerView.ViewHolder{
public TextView mTextViewTitle;
public TextView mTextViewBody;
public TextView mTextViewLink;
public Button mButton;
public portfolioViewHolder(View itemView) {
super(itemView);
mTextViewTitle = itemView.findViewById(R.id.text_view_title);
mTextViewBody = itemView.findViewById(R.id.text_view_body);
mTextViewLink = itemView.findViewById(R.id.text_view_link);
mButton = itemView.findViewById(R.id.share);
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mListenerShare != null){
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
mListenerShare.onItemClick(position);
}
}
}
});
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mListener != null){
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION) {
mListener.onItemClick(position);
}
}
}
});
}
}
}
解决方案
首先在 oncreate() 里面删除
mRecyclerView.setAdapter(mExampleAdapter);
在这段代码之后
mExampleAdapter = new ExampleAdapter(MainActivity.this, mExampleList);
mRecyclerView.setAdapter(mExampleAdapter);
添加这个: -
mExampleAdapter.notifyDataSetChanged();
推荐阅读
- typescript - 如何检查实例是否实现了接口
- angular - 没有在 Angular 中以反应形式获取所有值
- java - 打印映射值。如果参数是映射中的键,则打印关联的值,否则打印键不存在的输出
- javascript - 使用 offsetTop 或 getBoundingClientRect().top 返回错误值
- nsoutlineview - NSOutlineView 高亮样式
- sql - SQL SELECT 比较两个表中的值(没有 UNION ALL)
- ios - Swift 中用于单元测试的静态函数的依赖注入
- codenameone - 从设备 Codenameone 打开文件的问题
- javascript - 在 ES6 中,我们可以使用 {} 来引用 HTML 中的 JS 变量吗?
- java - Google 登录屏幕 Android 问题