我对 recyclerview 很陌生,所以我尝试转换一个 ListView ,我得到了这个:
public class WalletListRecyclerViewAdapter extends RecyclerView.Adapter<WalletListRecyclerViewAdapter.WalletItemHolder> {
ArrayList<WalletItem> walletItemList;
MainActivity context;
private static LayoutInflater inflater=null;
public WalletListRecyclerViewAdapter(MainActivity mainActivity, ArrayList<WalletItem> walletItemList) {
// TODO Auto-generated constructor stub
context = mainActivity;
this.walletItemList = walletItemList;
inflater = ( LayoutInflater )context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public WalletItemHolder onCreateViewHolder(final ViewGroup viewGroup, final int i) {
View rowView;
final DialogInterface.OnClickListener walletItemOnEditClickHandler = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
WalletItem.onClickEditButton(viewGroup,context,walletItemList,i);
}
};
final DialogInterface.OnClickListener walletItemOnDeleteClickHandler = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
walletItemList.remove(i);
RecyclerView rv = (RecyclerView) context.findViewById(R.id.recyclerView);
context.recreate();
}
};
View.OnClickListener walletItemOnClickHandler = new View.OnClickListener() {
@Override
public void onClick(View v) {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setNeutralButton("Edit",walletItemOnEditClickHandler);
builder.setPositiveButton("Delete",walletItemOnDeleteClickHandler);
builder.show();
}
};
rowView = inflater.inflate(R.layout.wallet_item, null);
return new WalletItemHolder(rowView);
}
@Override
public void onBindViewHolder(WalletItemHolder holder, int i) {
WalletItem wi = walletItemList.get(i);
SimpleDateFormat dateFormat = new SimpleDateFormat("E dd/MM/yyyy hh:mm");
holder.tvDescription.setText(wi.getDescription());
holder.tvAmount.setText(""+walletItemList.get(i).getAmount());
holder.tvDate.setText(dateFormat.format(walletItemList.get(i).getDate()));
holder.ivIcon.setImageResource(walletItemList.get(i).getImageResource());
}
public static class WalletItemHolder extends RecyclerView.ViewHolder {
public TextView tvDescription;
public TextView tvAmount;
public TextView tvDate;
public ImageView ivIcon;
/**
*Constructor
**/
public WalletItemHolder(View v) {
super(v);
tvDescription = (TextView) v.findViewById(R.id.textDescription);
tvAmount = (TextView) v.findViewById(R.id.textAmount);
tvDate = (TextView) v.findViewById(R.id.textDate);
ivIcon = (ImageView) v.findViewById(R.id.imageView1);
}
}
@Override
public int getItemCount() {
// TODO Auto-generated method stub
return walletItemList.size();
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
}
在我的 Activity 中使用
public class MainActivity extends AppCompatActivity {
private RecyclerView rv;
private Context context;
private MainActivity mainActivity = this;
private String m_DialogText = "";
private double m_DialogAmount = 0;
private WalletItem m_DialogResult = null;
private boolean drawn = false;
public static ArrayList<WalletItem> wlltList = new ArrayList<WalletItem>() ;// WalletItem.listBuilder(prgmImages, amountDummy, prgmNameList, dates);
private GoogleApiClient client;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
context = this;
wlltList.add(new WalletItem(R.drawable.testicongreen,15.0,"pippo",new Date()));
rv = (RecyclerView) findViewById(R.id.recyclerView);
if(wlltList != null) {
rv.setAdapter(new WalletListRecyclerViewAdapter(this, wlltList));
}
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
WalletItem.onClickAddButton(view,mainActivity,wlltList);
}
});
client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
}
ListView 工作正常,但我不知道我做错了什么,因为即使我添加了一些元素,RecyclerView 也显示为空
最佳答案
您还没有为您的 RecyclerView
设置 LayoutManager
。在设置适配器之前添加以下行。
rv.setLayoutManager(new LinearLayoutManager(this));
关于android - RecyclerView 显示为空,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38281686/