嗨，在下面的代码中，使用recyclerview显示列表时出现以下错误。 当我尝试显示列表时，出现以下错误。
java.lang.ClassCastException: java.lang.String cannot be cast to helper.GetBuildingList
at com.deepshikha.lightingsystem.SwipeRecyclerViewAdapter.onBindViewHolder(SwipeRecyclerViewAdapter.java:41)
at com.deepshikha.lightingsystem.SwipeRecyclerViewAdapter.onBindViewHolder(SwipeRecyclerViewAdapter.java:22)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6781)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6823)
响应：
[{"ID":"1","Name":"Building1"},{"ID":"2","Name":"appexx"}]
在下面的适配器中显示getbuildinglist pojo类中显示的内容。以及用户从右向左滑动后，我们将显示两个选项供列表项目编辑和删除。
SwipeAdapter：
public class SwipeRecyclerViewAdapter extends RecyclerSwipeAdapter<SwipeRecyclerViewAdapter.SimpleViewHolder> {
private Context mContext;
private List<GetBuildingList> buildingLists;
public SwipeRecyclerViewAdapter(Context context, List<GetBuildingList> strings) {
this.mContext = context;
this.buildingLists = strings;
}
@Override
public SimpleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.recyclerview_item, parent, false);
return new SimpleViewHolder(view);
}
@Override
public void onBindViewHolder(final SimpleViewHolder viewHolder, final int position) {
final GetBuildingList item = buildingLists.get(position);
System.out.println ("item"+item);
viewHolder.tvName.setText((item.getName ()) + " - Row Position " + position);
System.out.println (item.getName ());
viewHolder.swipeLayout.setShowMode(SwipeLayout.ShowMode.PullOut);
// Drag From Left
// viewHolder.swipeLayout.addDrag(SwipeLayout.DragEdge.Left, viewHolder.swipeLayout.findViewById(R.id.bottom_wrapper1));
// Drag From Right
viewHolder.swipeLayout.addDrag(SwipeLayout.DragEdge.Right, viewHolder.swipeLayout.findViewById(R.id.bottom_wrapper));
// Handling different events when swiping
viewHolder.swipeLayout.addSwipeListener(new SwipeLayout.SwipeListener() {
@Override
public void onClose(SwipeLayout layout) {
//when the SurfaceView totally cover the BottomView.
}
@Override
public void onUpdate(SwipeLayout layout, int leftOffset, int topOffset) {
//you are swiping.
}
@Override
public void onStartOpen(SwipeLayout layout) {
}
@Override
public void onOpen(SwipeLayout layout) {
//when the BottomView totally show.
}
@Override
public void onStartClose(SwipeLayout layout) {
}
@Override
public void onHandRelease(SwipeLayout layout, float xvel, float yvel) {
//when user's hand released.
}
});
/*viewHolder.swipeLayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if ((((SwipeLayout) v).getOpenStatus() == SwipeLayout.Status.Close)) {
//Start your activity
Toast.makeText(mContext, " onClick : " + item.getName() + " \n" + item.getEmailId(), Toast.LENGTH_SHORT).show();
}
}
});*/
viewHolder.swipeLayout.getSurfaceView().setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(mContext, " onClick : " + item.getName () + " \n" + item.getID (), Toast.LENGTH_SHORT).show();
}
});
// viewHolder.btnLocation.setOnClickListener(new View.OnClickListener() {
// @Override
// public void onClick(View v) {
//
// Toast.makeText(v.getContext(), "Clicked on Map " + viewHolder.tvName.getText().toString(), Toast.LENGTH_SHORT).show();
// }
// });
//
//
// viewHolder.tvShare.setOnClickListener(new View.OnClickListener() {
// @Override
// public void onClick(View view) {
//
// Toast.makeText(view.getContext(), "Clicked on Share " + viewHolder.tvName.getText().toString(), Toast.LENGTH_SHORT).show();
// }
// });
viewHolder.tvEdit.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast.makeText(view.getContext(), "Clicked on Edit " + viewHolder.tvName.getText().toString(), Toast.LENGTH_SHORT).show();
}
});
viewHolder.tvDelete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
mItemManger.removeShownLayouts(viewHolder.swipeLayout);
buildingLists.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, buildingLists.size());
mItemManger.closeAllItems();
Toast.makeText(view.getContext(), "Deleted " + viewHolder.tvName.getText().toString(), Toast.LENGTH_SHORT).show();
}
});
// mItemManger is member in RecyclerSwipeAdapter Class
mItemManger.bindView(viewHolder.itemView, position);
}
@Override
public int getItemCount() {
return buildingLists.size();
}
@Override
public int getSwipeLayoutResourceId(int position) {
return R.id.swipe;
}
// ViewHolder Class
public static class SimpleViewHolder extends RecyclerView.ViewHolder {
SwipeLayout swipeLayout;
TextView tvName;
TextView tvDelete;
TextView tvEdit;
public SimpleViewHolder(View itemView) {
super(itemView);
swipeLayout = (SwipeLayout) itemView.findViewById(R.id.swipe);
tvName = (TextView) itemView.findViewById(R.id.tvName);
// tvEmailId = (TextView) itemView.findViewById(R.id.tvEmailId);
tvDelete = (TextView) itemView.findViewById(R.id.tvDelete);
tvEdit = (TextView) itemView.findViewById(R.id.tvEdit);
// tvShare = (TextView) itemView.findViewById(R.id.tvShare);
// btnLocation = (ImageButton) itemView.findViewById(R.id.btnLocation);
}
}
}
在下面的代码中描述了不刷新活动的情况，我正在从服务器获取响应。 我添加到arraylist的响应，然后将适配器设置为recyclerview以显示带有滑动选项的项目列表。
Add.java：
private void doTheAutoRefresh() {
handler.postDelayed(new Runnable() {
@Override
public void run() {
// Write code for your refresh logic
progressDialog = new ProgressDialog (getActivity ());
progressDialog.setIndeterminate(true);
progressDialog.setMessage("Communicating...");
progressDialog.setCanceledOnTouchOutside(false);
progressDialog.setCancelable(false);
progressDialog.show();
OkHttpClient client = new OkHttpClient.Builder()
.connectTimeout(10, TimeUnit.SECONDS)
.writeTimeout(10, TimeUnit.SECONDS)
.readTimeout(30, TimeUnit.SECONDS)
.build();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(API.URL_BASE)
.addConverterFactory(ScalarsConverterFactory.create())
.addConverterFactory(GsonConverterFactory.create())
.client (client)
.build();
API service = retrofit.create (API.class);
Call<List<GetBuildingList>> userCall = service.getbuildinglist ();
userCall.enqueue(new Callback<List<GetBuildingList>> () {
@Override
public void onResponse(Call <List<GetBuildingList>> call, Response <List<GetBuildingList>> response) {
if(response.isSuccessful()) {
progressDialog.dismiss ( );
Log.d ("Response body", new Gson ( ).toJson (response.body ( )));
String Status = new Gson ( ).toJson (response.body ( ));
JSONArray jsonArray = null;
try {
JSONObject jsonObject=null;
jsonArray = new JSONArray (Status);
arrayList = new ArrayList <> ( );
for (int i=0;i<jsonArray.length ();i++) {
name=jsonArray.getJSONObject (i).getString ("Name");
arrayList.add (name);
}
// Creating Adapter object
SwipeRecyclerViewAdapter mAdapter = new SwipeRecyclerViewAdapter((Context) getActivity (), arrayList);
mAdapter.notifyDataSetChanged ();
mRecyclerView.setAdapter(mAdapter);
} catch (JSONException e) {
e.printStackTrace ( );
}
}
else {
progressDialog.dismiss ();
Log.d("Response errorBody", String.valueOf(response.errorBody()));
}
}
@Override
public void onFailure(Call<List<GetBuildingList>> call, Throwable t) {
// lv.setAdapter (adapter);
System.out.println("onFailure");
System.out.println(t.fillInStackTrace());
progressDialog.dismiss();
Toast.makeText(getActivity (), "Some error occurred -> ", Toast.LENGTH_LONG).show();;
// progressDialog.dismiss();
}
});
}
}, 5000);
return ;
}
GetBuildingList.java：
public class GetBuildingList{
@SerializedName("ID")
private String ID;
@SerializedName("Name")
private String Name;
public String getID() {
return ID;
}
public void setID(String ID) {
this.ID = ID;
}
public String getName() {
return Name;
}
public void setName(String name) {
Name = name;
}
}
答案 0 :(得分：1)
在您的onResponse()方法中，这些行如下：
name=jsonArray.getJSONObject (i).getString ("Name");
...
arrayList.add (name);
然后将此列表传递给适配器。该列表已分配给适配器的GetBuildingList字段。然后在适配器中执行以下操作：
final GetBuildingList item = buildingLists.get(position);
因此，您尝试将String类型转换为GetBuildingList类型，因此是例外。
对图书馆不是很熟悉，但是您应该尝试这样的事情：
for (int i=0;i<jsonArray.length ();i++) {
String name = jsonArray.getJSONObject (i).getString ("Name");
String id = jsonArray.getJSONObject (i).getString ("Id");
GetBuildingList gbl = new GetBuildingList();
gbl.setId(id);
gbl.setName(name);
arrayList.add(gbl);
}
我还没有使用过这个库，所以如果我错了，请有人更正上面的示例。