我有这样的想法，当用户按下晶圆厂时，卡片视图会添加到recyclerview布局中。用户添加的每个cardview内都有一个微调框，复选框edittext和textview。微调框由csv文件中的第一列填充。第一列具有商品名称，第二列具有与该产品相关的特定编号，其中一些可以相同
我以前有一个类似的应用程序，当用户从微调器中选择一个项目时，csv文件中的核心对应数字将显示在文本视图中。但是那没有recyclerviews或cardviews，所以我现在尝试在我的代码中实现它（使用recyclerview和cardviews）
但是，当我试图在当前的ProductAdapter（recyclerviewadapter）代码中实现该代码时，却出现了一个错误：
编译错误：
error: cannot find symbol method getResources()
它来自这段代码
InputStream inputStream = getResources().openRawResource(R.raw.shopitems);
CSVFile csvFile = new CSVFile(inputStream);
final List<String> mSpinnerItems = csvFile.read();
这是我完整的ProductAdapter.java代码
public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductViewHolder> {
private Map<Integer, Integer> mSpinnerSelectedItem = new HashMap<Integer, Integer>();
private Map<String, String> numberItemValues = new HashMap<>();
private SearchableSpinner spinner;
//we are storing all the products in a list
private List<Product> productList;
private Activity create;
//TODO CODE FOR CSV FILE
/*InputStream inputStream = getResources().openRawResource(R.raw.shopitems);
CSVFile csvFile = new CSVFile(inputStream);
final List<String> mSpinnerItems = csvFile.read();*/
InputStream inputStream = null;
List<String> mSpinnerItems = null;
CSVFile csvFile = null;
//TODO END OF CODE FOR CSV FILE
public ProductAdapter(Activity activity) {
create = activity;
}
//getting the context and product list with constructor
public ProductAdapter(Activity activity, List<Product> productList) {
// this.mCtx = mCtx;
/* inputStream = create.getResources().openRawResource(R.raw.shopitems);
csvFile = new CSVFile(inputStream);
mSpinnerItems = csvFile.read();*/
create = activity;
this.productList = productList;
}
@Override
public ProductViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//inflating and returning our view holder
LayoutInflater inflater = LayoutInflater.from(create);
View view = inflater.inflate(R.layout.layout_products, null);
return new ProductViewHolder(view);
}
@Override
public void onBindViewHolder(final ProductViewHolder holder, final int position) {
// //getting the product of the specified position
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(create, R.layout.item_spinner_layout,
Product.getSpinnerItemsList());
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
holder.spinner.setAdapter(spinnerArrayAdapter);
holder.spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int mPosition, long id) {
mSpinnerSelectedItem.put(position, mPosition);
TextView mTextView = view.findViewById(R.id.mSpinnerText);
//TODO CODE FOR GETTING AISLE NUMBER AND PUTTING IT IN THE TEXTVIEW
String currentItem = mSpinnerItems.get(position);
String aisleNumber = numberItemValues.get(currentItem);
holder.textView5.setText(aisleNumber);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
//binding the data with the viewholder views
if (mSpinnerSelectedItem.containsKey(position)) {
holder.spinner.setSelection(mSpinnerSelectedItem.get(position));
}
holder.getView().setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(create);
// set title
alertDialogBuilder.setTitle("Delete Item");
// set dialog message
alertDialogBuilder
.setMessage("Are you sure you want to delete this item?")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// if this button is clicked, close
// current activity
holder.checkBox.setChecked(false);
holder.spinner.setSelection(0);
productList.remove(holder.getAdapterPosition());
notifyItemRemoved(holder.getAdapterPosition());
Toast.makeText(create, "Item removed.", Toast.LENGTH_LONG).show();
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();
// show it
alertDialog.show();
}
});
}
@Override
public int getItemCount() {
return productList.size();
}
class ProductViewHolder extends RecyclerView.ViewHolder {
SearchableSpinner spinner;
EditText editText;
TextView textView5;
CheckBox checkBox;
LinearLayout linearLayout;
View rootView;
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);
rootView = itemView.findViewById(R.id.linearLayout);
checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// makes the set disappear when checkbox is ticked.
if(isChecked){
checkBox.setChecked(false);
spinner.setSelection(0);
productList.remove(getAdapterPosition());
notifyItemRemoved(getAdapterPosition());
Toast.makeText(create, "Done!", Toast.LENGTH_LONG).show();
}
}
});
}
public View getView() {
return rootView;
}
}
//TODO CODE FOR CSV FILE
private class CSVFile {
InputStream inputStream;
public CSVFile(InputStream inputStream) {
this.inputStream = inputStream;
}
public List<String> read() {
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(",");
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;
}
}
}
create.java代码，这是我的主要活动，其中添加了卡，而晶圆厂等
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<>();
private Map<Integer, Integer> mSpinnerSelectedItem = new HashMap<Integer, Integer>();
@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<>();
productList.add(new Product(mSpinnerItems, "Test Edit Text",false, "Text String 2"));
final ProductAdapter adapter = new ProductAdapter(this, productList);
//TODO FAB BUTTON
FloatingActionButton floatingActionButton =
findViewById(R.id.fab);
floatingActionButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
productList.add(mProduct);
if(adapter != null)
adapter.notifyDataSetChanged();
//Handle the empty adapter here
}
});
//setting adapter to recyclerview
recyclerView.setAdapter(adapter);
}
private class CSVFile {
InputStream inputStream;
public CSVFile(InputStream inputStream) {
this.inputStream = inputStream;
}
public List<String> read() {
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;
}
}
}
答案 0 :(得分：1)
适配器了解关于// val list = List(Success(10), Success(20), Failure(new Exception("error1")))
val (failures, successes) = list.partitionMap(_.toEither)
// failures: List[Throwable] = List(java.lang.Exception: error1)
// successes: List[Int] = List(10, 20)
的想法。这需要来自getResources()或Activity对象。这样做：
Context然后在您的公开InputStream inputStream = null;
List<String> mSpinnerItems = null;
CSVFile csvFile = null;
方法中正确初始化ProductAdapter()。
InputStream当然，您可以创建一个public ProductAdapter(Activity activity, List<Product> productList) {
create = activity;
//INFO:: Now initialize the InputStream
inputStream = create.getResources().openRawResource(R.raw.shopitems);
csvFile = new CSVFile(inputStream);
mSpinnerItems = csvFile.read();
this.productList = productList;
}
资源，并使用该资源填充微调器视图。
string-array然后在布局文件中：
<string-array name="my_values">
<item>Hello</item>
<item>World</item>
<item>Back</item>
<item>Again</item>
</string-array>
。
编辑
使用更新后的代码，您可以删除：
<Spinner
android:id="@+id/spinner"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:drawSelectorOnTop="true"
android:entries="@array/my_values"
/>
来自InputStream inputStream = null;
List<String> mSpinnerItems = null;
CSVFile csvFile = null;
。
在行：
上发生的ProductAdapter错误
NullPointerException是由于不再使用String currentItem = mSpinnerItems.get(position);
并将其设置为mSpinnerItems引起的。因此，为了获得微调器中选择的值，请执行以下操作：
null。
新编辑：
在 holder.spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int mPosition, long id) {
mSpinnerSelectedItem.put(position, mPosition);
TextView mTextView = view.findViewById(R.id.mSpinnerText);
//TODO CODE FOR GETTING AISLE NUMBER AND PUTTING IT IN THE TEXTVIEW
//SearchableSpinner spinner = (SearchableSpinner)view;
String currentItem = holder.spinner.getItemAtPosition(mPosition).toString();
// or try
// spinner.getAdapter.getItem(mPosition).toString();
String aisleNumber = numberItemValues.get(currentItem);
holder.textView5.setText(aisleNumber);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
中使用此：
ProductAdapter并在“创建” public ProductAdapter(Activity activity, List<Product> productList, HashMap<String, String> numberList) {
numberItemValues = numberList;
create = activity;
this.productList = productList;
}
中更改此行：
Activity