当用户按下FAB时，卡片视图出现在recyclerview中。在cardview内部是一个带有其他元素的微调框。当我添加多个cardview并从微调器中选择一个项目时，然后我从fab添加另一个cardview，然后所有微调器选择的项目都重置了吗？
我有一个方法productList.size（），该方法可能有助于保存微调器选择的值，但我不知道从这里去哪里。谢谢
活动代码
public class create extends AppCompatActivity {
//a list to store all the products
List<Product> productList;
//the recyclerview
RecyclerView recyclerView;
Product mProduct;
private Map<String, String> numberItemValues = new HashMap<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.create);
//opens csv
InputStream inputStream = getResources().openRawResource(R.raw.shopitems);
CSVFile csvFile = new CSVFile(inputStream);
final List<String> mSpinnerItems = csvFile.read();
//getting the recyclerview from xml
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
//initializing the productlist
productList = new ArrayList<>();
final Spinner spinner;
final EditText editText;
final CheckBox checkBox;
final TextView textView5;
spinner = findViewById(R.id.spinner);
editText = findViewById(R.id.editText);
checkBox = findViewById(R.id.checkBox);
textView5 = findViewById(R.id.textView5);
final ProductAdapter adapter = new ProductAdapter(this, productList);
//TODO FAB BUTTON
FloatingActionButton floatingActionButton =
(FloatingActionButton) findViewById(R.id.fab);
floatingActionButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
List<Product> mProductList = new ArrayList<>();
productList.add(mProduct);
if(adapter != null)
adapter.notifyDataSetChanged();
//Handle the empty adapter here
}
});
/* //TODO Add the spinner on item selected listener to get selected items
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
String currentItem = mSpinnerItems.get(position);
String aisleNumber = numberItemValues.get(currentItem);
//TODO you can use the above aisle number to add to your text view
//mTextviews.get(mTextviews.size() -1).setText(aisleNumber);
textView5.setText(aisleNumber);
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// do nothing
}
});*/
//setting adapter to recyclerview
recyclerView.setAdapter(adapter);
}
private class CSVFile {
InputStream inputStream;
public CSVFile(InputStream inputStream) {
this.inputStream = inputStream;
}
public List<String> read() {
// The problem with your adapter is solved now you need to do some work here its giving an error while reading the file
//why is it giving an error because it use to work fine before I added cardview and recyclerview
//Is the file there?
List<String> resultList = new ArrayList<String>();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
try {
String line;
while ((line = reader.readLine()) != null) {
String[] row = line.split(",");
//TODO I edited this part so that you'd add the values in our new hash map variable
numberItemValues.put(row[1], row[0]);
resultList.add(row[1]);
}
} catch (IOException e) {
Log.e("Main", e.getMessage());
} finally {
try {
inputStream.close();
} catch (IOException e) {
Log.e("Main", e.getMessage());
}
}
return resultList;
}
}
}
product.java代码
public class Product {
private static String editText;
private static Boolean checkBox;
private static String textView5;
// The following list is useless unless u don't use it somewhere so lets create getters and setters for this item
public static List<String> spinnerItemsList = new ArrayList<String>();
public Product(List spinner, String editText, Boolean checkBox, String textView5) {
this.editText = editText;
this.spinnerItemsList = spinner;
this.checkBox = checkBox;
this.textView5 = textView5;
}
public static String getEdittext () {
return editText;
}
public static boolean getCheckbox () {
return checkBox;
}
public static String getTextview () {
return textView5;
}
public static List<String> getSpinnerItemsList () {
return spinnerItemsList;
}
}
productadapter.java
public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductViewHolder> {
//this context we will use to inflate the layout
private Context mCtx;
private Spinner spinner;
//we are storing all the products in a list
private List<Product> productList;
//getting the context and product list with constructor
public ProductAdapter(Context mCtx, List<Product> productList) {
this.mCtx = mCtx;
this.productList = productList;
}
@Override
public ProductViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//inflating and returning our view holder
LayoutInflater inflater = LayoutInflater.from(mCtx);
View view = inflater.inflate(R.layout.layout_products, null);
return new ProductViewHolder(view);
}
@Override
public void onBindViewHolder(ProductViewHolder holder, int position) {
//getting the product of the specified position
Product product = productList.get(position);
//binding the data with the viewholder views
//MyListAdapter adapter = new MyListAdapter(mCtx, R.layout.listrow, R.id.txtid, Product.spinnerItemsList);
//spinner.setAdapter(adapter);
//Try using Simple ArrayAdapter if all you need to display is one text
//Lets see
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String> (mCtx, android.R.layout.simple_spinner_item, Product.getSpinnerItemsList());
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//Did it work?
//yes but when I press the spinner I do not see the items that usually comes up also the layout of Oit Oipen the screen let me take the screen shot
//how do i do that? the screen is open on my phone ok wait click the spinner yes
//There is no item??
//nothing comes up. not even a dropdown. but before i had it like it was populated by items in a csv.
//Okay wait let me get your old code
//also, I added cardviews in my phone but i try to scroll up and I cannot? i thought you could scroll in recyclerview?
//Yes you can scroll it should work
holder.spinner.setAdapter(spinnerArrayAdapter);
}
@Override
public int getItemCount() {
return productList.size();
}
class ProductViewHolder extends RecyclerView.ViewHolder {
Spinner spinner;
EditText editText;
TextView textView5;
CheckBox checkBox;
public ProductViewHolder(View itemView) {
super(itemView);
spinner = itemView.findViewById(R.id.spinner);
editText = itemView.findViewById(R.id.editText);
textView5 = itemView.findViewById(R.id.textView5);
checkBox = itemView.findViewById(R.id.checkBox);
}
}
}
** mylistadapter.java，适用于微调器**
public class MyListAdapter extends ArrayAdapter<String> {
int groupid;
List<String> items;
Context context;
String path;
public MyListAdapter(Context context, int vg, int id, List<String> items) {
super(context, vg, id, items);
this.context = context;
groupid = vg;
this.items = items;
}
static class ViewHolder {
public TextView textid;
public TextView textname;
}
@Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
{
View rowView = convertView;
if (rowView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rowView = inflater.inflate(groupid, parent, false);
ViewHolder viewHolder = new ViewHolder();
viewHolder.textid = (TextView) rowView.findViewById(R.id.txtid);
viewHolder.textname = (TextView) rowView.findViewById(R.id.txtname);
rowView.setTag(viewHolder);
}
// Fill data in the drop down.
ViewHolder holder = (ViewHolder) rowView.getTag();
String row = items.get(position);
//holder.textid.setText(row[0]); //prints aisle number, dont need
holder.textname.setText(row);
return rowView;
}
}
}
答案 0 :(得分：1)
有多个步骤可以实现这一目标：
第1步：
Map<Integer, Integer> mSpinnerSelectedItem = new HashMap<Integer, Integer>();
第2步：
在onBindViewHolder内添加以下行
if (mSpinnerSelectedItem.containsKey(position)) {
spinner.setSelection(mSpinnerSelectedItem.get(position));
}
第3步：
现在，在您设置微调器onItemSelected方法的位置，添加以下行来存储该微调器的所选项目。
mSpinnerSelectedItem.put(position, selectedIndex);