【发布时间】:2018-10-02 09:00:48
【问题描述】:
我有以下代码用于使用 Firebase 的 recyclerview。 Recycler View 使用以下适配器。
FirebaseRecyclerAdapter<DownloadList,DownloadListFragment.DownloadViewHolder> recyclerAdapter= new FirebaseRecyclerAdapter<DownloadList, DownloadViewHolder>(
DownloadList.class,
R.layout.download_cardview,
DownloadViewHolder.class,
databaseReference
) {
@Override
protected void populateViewHolder(DownloadViewHolder viewHolder, DownloadList model, int position) {
viewHolder.setTitle(model.gettitle());
//viewHolder.setImage(model.getimage());
viewHolder.setDate(model.getDate());
}
@Override
public DownloadViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
DownloadViewHolder viewHolder = super.onCreateViewHolder(parent, viewType);
viewHolder.setOnClickListener(new DownloadViewHolder.ClickListener() {
@Override
public void onItemClick(View view, int position) {
Toast.makeText(getActivity(), "Item click at " + arrayAdapter.getItem(position), Toast.LENGTH_SHORT).show();
DownloadImageFragment fragment = new DownloadImageFragment();
Bundle arguments = new Bundle();
arguments.putString( "Batch" , batchID);
arguments.putString( "Type" , typeID);
arguments.putString( "Url", arrayAdapter.getItem(position));
arguments.putString( "Title", (String) titleAdapter.getItem(position));
fragment.setArguments(arguments);
final FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.replace(R.id.content, fragment , "Download List");
ft.commit();
}
@Override
public void onItemLongClick(View view, int position) {
return ;
}
});
return viewHolder;
}
};
recyclerView.setAdapter(recyclerAdapter);
return view;
}
public static class DownloadViewHolder extends RecyclerView.ViewHolder {
View mView;
TextView textView_Title;
TextView textView_Date;
TextView textView_Image;
String simage,stitle;
private static Context context;
public DownloadViewHolder(View itemView) {
super(itemView);
mView = itemView;
context = itemView.getContext();
textView_Title = (TextView) itemView.findViewById(R.id.textView_download_title);
textView_Image = (TextView) itemView.findViewById(R.id.textView_image_download);
textView_Date = (TextView) itemView.findViewById(R.id.textView_download_date);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mClickListener.onItemClick(v, getAdapterPosition());
}
});
itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
mClickListener.onItemLongClick(v, getAdapterPosition());
return true;
}
});
}
getter 和 setter 定义为:
public class DownloadList {
private String date;
private String title;
private String image;
public DownloadList(){}
public DownloadList(String date, String title, String image){
this.date = date;
this.title = title;
this.image = image;
}
public String getDate(){
return date;
}
public void setDate(String date){
this.date = date;
}
public String gettitle(){
return title;
}
public void setTitle(String title){
this.title = title;
}
public String getimage(){
return image;
}
public void setimage(String description){
this.image = image;
}
}
现在在构建 apk 时会弹出以下错误
错误:类中的构造函数 FirebaseRecyclerAdapter FirebaseRecyclerAdapter 不能应用于给定类型; 必需:找到 FirebaseRecyclerOptions: 类,整数,类,数据库引用 原因:实际参数列表和形式参数列表的长度不同,其中 T,VH 是类型变量: T 扩展类中声明的对象 FirebaseRecyclerAdapter VH 扩展了在类中声明的 ViewHolder FirebaseRecyclerAdapter
这在 android studio 3.1 更新之前(2018 年 3 月)是不存在的。
我曾尝试更改 app:compatv7 版本,但仍然无法正常工作。
还根据FirebaseUI for Realtime Database提供的文档,它说要使用
Query query = FirebaseDatabase.getInstance()
.getReference()
.child("chats")
.limitToLast(50);
和
FirebaseRecyclerOptions<Chat> options =
new FirebaseRecyclerOptions.Builder<Chat>()
.setQuery(query, Chat.class)
.build();
现在我的问题是,因为我已经在应用程序的 15 个不同位置使用了上述 recyclerView,所以我需要在所有 15 个位置更改它还是 还有其他方法?另外是否可以保证如果我使用查询,新代码将兼容?
【问题讨论】:
标签: android firebase firebase-realtime-database android-recyclerview firebaseui