[英]Recyclerview adapter with CursorAdapter
我想实现一个适配器Recyclerview
与使用CusrorAdapter
如下作为解决方案的一个建议这里 。
我是Android的新手,我不太了解如何重写CursorAdapter
的newView方法和bindView
方法。 我也是猜我的适配器将有多个变量ViewHolder
,而不是一个(查看V1)因为有几个textViews
在我的布局文件,但我只是不知道如何将它们中的代码。
public class MyRecyclerAdapter extends Adapter<MyRecyclerAdapter.ViewHolder {
// PATCH: Because RecyclerView.Adapter in its current form doesn't natively support
// cursors, we "wrap" a CursorAdapter that will do all teh job for us
CursorAdapter mCursorAdapter;
Context mContext;
public MyRecyclerAdapter(Context context, Cursor c) {
mContext = context;
mCursorAdapter = new CursorAdapter(mContext, c, 0) {
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
// Inflate the view here
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
// Binding operations
}
};
}
public static class ViewHolder extends RecyclerView.ViewHolder{
View v1;
public ViewHolder(View itemView) {
super(itemView);
v1 = itemView.findViewById(R.id.v1);
}
}
@Override
public int getItemCount() {
return mCursorAdapter.getCount();
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
// Passing the binding operation to cursor loader
mCursorAdapter.bindView(holder.itemView, mContext, mCursorAdapter.getCursor());
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// Passing the inflater job to the cursor-adapter
View v = mCursorAdapter.newView(mContext, mCursorAdapter.getCursor(), parent);
return new ViewHolder(v);
}
}
尽管我不了解它的细节,但还是设法使它起作用。 基本上,我添加了ViewHolder
变量作为类变量,并更改了代码的某些部分。 当您在名为row.xml
的布局文件中有2个TextView
项( name
和date
)时,解决方案如下row.xml
:
public class MyRecyclerAdapter extends Adapter<MyRecyclerAdapter.ViewHolder>{
// PATCH: Because RecyclerView.Adapter in its current form doesn't natively support
// cursors, we "wrap" a CursorAdapter that will do all teh job for us
private CursorAdapter mCursorAdapter;
private Context mContext;
private ViewHolder holder;
public MyRecyclerAdapter(Context context, Cursor c) {
mContext = context;
mCursorAdapter = new CursorAdapter(mContext, c, 0) {
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
// Inflate the view here
View v = LayoutInflater.from(context)
.inflate(R.layout.row_rv, parent, false);
return v;
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
// Binding operations
String name = cursor.getString(cursor.getColumnIndexOrThrow("name"));
String date = cursor.getString(cursor.getColumnIndexOrThrow("date"));
holder.tvName.setText(name);
holder.tvDate.setText(date);
}
};
}
public static class ViewHolder extends RecyclerView.ViewHolder{
public TextView tvName;
public TextView tvDate;
public ViewHolder(View itemView) {
super(itemView);
tvName = (TextView) itemView.findViewById(R.id.name);
tvDate = (TextView) itemView.findViewById(R.id.date);
}
}
@Override
public int getItemCount() {
return mCursorAdapter.getCount();
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
// Passing the binding operation to cursor loader
mcursorAdapter.getCursor().moveToPosition(position);
mCursorAdapter.bindView(holder.itemView, mContext, mCursorAdapter.getCursor());
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// Passing the inflater job to the cursor-adapter
View v = mCursorAdapter.newView(mContext, mCursorAdapter.getCursor(), parent);
holder = new ViewHolder(v);
return holder;
}
}
如果有人知道它为什么起作用,请随时加入讨论。 谢谢。
而不是使用View创建ViewHolder,而应使用布局上具有的所有对象(所需的所有元素)创建ViewHolder。 必须在onCreateViewHolder方法中创建(填充)布局视图。
像这样:
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>
{
class ViewHolder extends RecyclerView.ViewHolder {
TextView textView1;
TextView textView2;
public ViewHolder(View itemView) {
super(itemView);
textView1 = (TextView) itemView.findViewById(R.id.textView1);
textView2 = (TextView) itemView.findViewById(R.id.textView2);
}
public void insertView(String result1, String result2) {
textView1.setText(result1);
textView2.setText(result2);
}
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_name, parent, false);
RecyclerView.ViewHolder viewHolder = new ViewHolder(itemView);
return viewHolder;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
((ViewHolder) holder).insertView(results.get(position).getResult1(), results.get(position).getResult2());
}
@Override
public int getItemCount() {
return results.size();
}
}
您可以使用ORMSugar进行持久化。 不过,如果您可以访问适配器外部的数据库,那就更好了。 您将从数据库中获取必要的信息,并将该信息传递给适配器构造函数。
如果您需要一个例子,只需要告诉我即可。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.