Recylerview仅显示最后添加的数据，并且也替换以前添加的数据；

Question

我想在回收者视图中显示数据，但它仅显示最后添加的数据，而不显示以前添加的数据我尝试了sqlite数据库，但是它没有用，所以我尝试了第一个ststic数据，但是它也显示了同样的错误。我尝试使用Google搜索，但是在此问题上没有任何工作。我也尝试notifydatachanged（），但也没有用。这是我的适配器代码：

public class fileAdapter extends RecyclerView.Adapter<fileAdapter.ViewHolder> {

private final Context context;
private ArrayList<files> filelist;
private dbhelper mdb;
public fileAdapter(Context context, ArrayList<files> filelist){
    this.context=context;
    this.filelist=filelist;
    mdb=new dbhelper(context);

}

@Override
public ViewHolder onCreateViewHolder( ViewGroup viewGroup, int i) {
    View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.row_file, viewGroup, false);
    ViewHolder holder=new ViewHolder(v);
    return holder;
}

@Override
public void onBindViewHolder(fileAdapter.ViewHolder viewHolder, int i) {
    final files file=filelist.get(i);
    viewHolder.name.setText(file.getFname());
    viewHolder.time.setText(file.getTime());

    ViewHolder.relativeLayout.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Toast.makeText(view.getContext(),"click on item: "+files.getFname(),Toast.LENGTH_LONG).show();
        }
    });

}

@Override
public int getItemCount() {
    return filelist.size();
}


public static class ViewHolder extends RecyclerView.ViewHolder {
    public TextView name,time;
    public static RelativeLayout relativeLayout;
    public ViewHolder(View v) {
        super(v);
        name=(TextView)v.findViewById(R.id.name);
        time=(TextView)v.findViewById(R.id.time);
        relativeLayout=(RelativeLayout)v.findViewById(R.id.listraw);
    }
}

}

这是我的活动

 private static final String TAG = MainActivity.class.getSimpleName();
private dbhelper db;
private ArrayList<files> allfiles=new ArrayList<>();
private fileAdapter madapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_activity2);

    RecyclerView recyclerView = (RecyclerView)findViewById(R.id.rec1);
    RecyclerView.LayoutManager linearLayoutManager = new LinearLayoutManager(this);
    recyclerView.setLayoutManager(linearLayoutManager);

    madapter = new fileAdapter(this,allfiles);
    recyclerView.setAdapter(madapter);

    newdata();





}

private void newdata() {
    files file=new files("1","e");
    allfiles.add(file);

     file=new files("2","4");
    allfiles.add(file);
    file=new files("3","5");
    allfiles.add(file);

    file=new files("4","6");
    allfiles.add(file);

    file=new files("5","7");
    allfiles.add(file);
    madapter.notifyDataSetChanged();
}

}

每当我在Recylcer视图中获取数据时，它仅显示最后添加的数据。

activiy.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:context=".activity2">
<android.support.v7.widget.RecyclerView
    android:id="@+id/rec1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:scrollbars="vertical"
    />

list_raw.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/listraw"
android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="wrap_content">


<android.support.v7.widget.CardView

    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:elevation="10dp"
    android:layout_margin="5dp">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:weightSum="1">

        <TextView
            android:id="@+id/name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:layout_gravity="center_horizontal"
            android:layout_marginEnd="50dp"
            android:layout_weight="1"

            />

        <TextView
            android:id="@+id/time"
            android:layout_gravity="center_horizontal"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:layout_weight="1"

             />
    </LinearLayout>
</android.support.v7.widget.CardView>

Answer 1

尝试使用这种方式添加数据：

Answer 2

private static final String TAG = MainActivity.class.getSimpleName();
private dbhelper db; 
private ArrayList<files> allfiles=new ArrayList<>(); 
private fileAdapter madapter;

        @Override protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_activity2);

            RecyclerView recyclerView = (RecyclerView)findViewById(R.id.rec1);
            RecyclerView.LayoutManager linearLayoutManager = new LinearLayoutManager(this);
            recyclerView.setLayoutManager(linearLayoutManager);

            madapter = new fileAdapter(this,allfiles);
            recyclerView.setAdapter(madapter);

            newdata();





        }

        private void newdata() {
            files file=new files("1","e");
            allfiles.add(file);

             file=new files("2","4");
            allfiles.add(file);
            file=new files("3","5");
            allfiles.add(file);

            file=new files("4","6");
            allfiles.add(file);

            file=new files("5","7");
            allfiles.add(file);
            madapter.notifyDataSetChanged(); 
    }
}