我在这一行收到错误：
task.setOnArticleSelectedListener(this);
我得到的错误是：
setOnArticleSelectedListener
(com.beerportfolio.beerportfoliopro.PortfolioGetAllBeers.OnArticleSelectedListener)
in PortfolioGetAllBeers cannot be applied
to
(android.widget.AdapterView.OnItemSelectedListener)
该代码来自：
public class Portfolio extends Fragment implements PortfolioGetAllBeers.OnArticleSelectedListener {
String beerId = "";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//set layout here
final View theLayout = inflater.inflate(R.layout.activity_portfolio, container, false);
setHasOptionsMenu(true);
getActivity().setTitle("Style");
//get user information
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getActivity());
String userName = prefs.getString("userName", null);
String userID = prefs.getString("userID", null);
final Spinner portfolioType = (Spinner) theLayout.findViewById(R.id.portfolioSpinner);
portfolioType.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
String portfolioChoice = portfolioType.getSelectedItem().toString();
Log.d("portfolio", portfolioChoice);
if( portfolioChoice.equals("All")){
//todo: clear second spinner
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "myURL";
//async task goes here
PortfolioGetAllBeers task = new PortfolioGetAllBeers(getActivity());
task.setOnArticleSelectedListener(this);
task.execute(url);
}
else if (portfolioChoice.equals("Brewery")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//todo: get breweries and fill spinner
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "myURL2";
//async task goes here
new PortfolioGetAllBreweries(selectedItemView.getContext()).execute(url);
}
else if (portfolioChoice.equals("Style")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "http://beerportfolio.com/app_getAllYourStyles.php?u=" + userID;
//todo: async task goes here
new PortfolioGetAllStyles(selectedItemView.getContext()).execute(url);
}
else if (portfolioChoice.equals("Rating")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//make array
//make array list for beer
final List<String> tasteList = new ArrayList<String>();
tasteList.add("1");
tasteList.add("2");
tasteList.add("3");
tasteList.add("4");
tasteList.add("5");
// Selection of the spinner
Spinner spinner = (Spinner) theLayout.findViewById(R.id.portfolioSpinner2);
// Application of the Array to the Spinner
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(selectedItemView.getContext(), android.R.layout.simple_spinner_item,tasteList );
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
spinner.setAdapter(spinnerArrayAdapter);
//todo: add on select for spinner 2
//add on item selected
final Spinner portfolioType = (Spinner) theLayout.findViewById(R.id.portfolioSpinner2);
portfolioType.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
String portfolioChoice = portfolioType.getSelectedItem().toString();
//Toast.makeText(((Activity) c).getApplicationContext(), portfolioChoice, Toast.LENGTH_LONG).show();
final ListView lv = (ListView) theLayout.findViewById(R.id.allYourBeersList);
lv.setAdapter(null);
//get brewery beers
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
try {
portfolioChoice = URLEncoder.encode(portfolioChoice, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
//construct url
String url = "myURL3";
Log.d("portfolio" , url);
//async task goes here
new PortfolioGetAllBeers(selectedItemView.getContext()).execute(url);
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// do nothing
}
});
}
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// do nothing
}
});
// Inflate the layout for this fragment
return theLayout;
}
@Override
public void onArticleSelected(String bID, String brewery){
//code to execute on click
Fragment Fragment_one;
FragmentManager man= getFragmentManager();
FragmentTransaction tran = man.beginTransaction();
Fragment_one = new BeerPage();
final Bundle bundle = new Bundle();
bundle.putString("beerIDSent", bID);
bundle.putString("breweryIDSent", brewery);
Fragment_one.setArguments(bundle);
tran.replace(R.id.main, Fragment_one);//tran.
tran.addToBackStack(null);
tran.commit();
}
}
然后异步任务代码是：
public class PortfolioGetAllBeers extends AsyncTask<String, Void, String> {
Context c;
private ProgressDialog Dialog;
public PortfolioGetAllBeers (Context context)
{
c = context;
Dialog = new ProgressDialog(c);
}
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
return readJSONFeed(arg0[0]);
}
protected void onPreExecute() {
Dialog.setMessage("Getting beers");
Dialog.setTitle("Loading");
Dialog.setCancelable(false);
Dialog.show();
}
//***************************code for on click
OnArticleSelectedListener listener;
public interface OnArticleSelectedListener{
public void onArticleSelected(String myString , String brewery);
}
public void setOnArticleSelectedListener(OnArticleSelectedListener listener){
this.listener = listener;
}
//*****************************end code for onClick
protected void onPostExecute(String result){
//decode json here
try{
JSONArray jsonArray = new JSONArray(result);
//acces listview
ListView lv = (ListView) ((Activity) c).findViewById(R.id.allYourBeersList);
//make array list for beer
final List<ShortBeerInfo> tasteList = new ArrayList<ShortBeerInfo>();
for(int i = 0; i < jsonArray.length(); i++) {
String beer = jsonArray.getJSONObject(i).getString("beer");
String rate = jsonArray.getJSONObject(i).getString("rate");
String beerID = jsonArray.getJSONObject(i).getString("id");
String bID = jsonArray.getJSONObject(i).getString("breweryID");
//create object
ShortBeerInfo tempTaste = new ShortBeerInfo(beer, rate, beerID, bID);
//add to arraylist
tasteList.add(tempTaste);
}
//add items to listview
ShortBeerInfoAdapter adapter1 = new ShortBeerInfoAdapter(c ,R.layout.brewer_stats_listview, tasteList);
lv.setAdapter(adapter1);
//set up clicks
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
ShortBeerInfo o=(ShortBeerInfo)arg0.getItemAtPosition(arg2);
String tempID = o.id;
String tempBrewID = o.brewery;
//todo: go to beer page
listener.onArticleSelected(tempID, tempBrewID);
}
});
}
catch(Exception e){
}
Dialog.dismiss();
}
public String readJSONFeed(String URL) {
StringBuilder stringBuilder = new StringBuilder();
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(URL);
try {
HttpResponse response = httpClient.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream inputStream = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
stringBuilder.append(line);
}
inputStream.close();
} else {
Log.d("JSON", "Failed to download file");
}
} catch (Exception e) {
Log.d("readJSONFeed", e.getLocalizedMessage());
}
return stringBuilder.toString();
}
}
更新代码：
public class Portfolio extends Fragment implements PortfolioGetAllBeers.OnArticleSelectedListener {
String beerId = "";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//set layout here
final View theLayout = inflater.inflate(R.layout.activity_portfolio, container, false);
setHasOptionsMenu(true);
getActivity().setTitle("Style");
//get user information
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getActivity());
String userName = prefs.getString("userName", null);
String userID = prefs.getString("userID", null);
final Spinner portfolioType = (Spinner) theLayout.findViewById(R.id.portfolioSpinner);
portfolioType.OnArticleSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
String portfolioChoice = portfolioType.getSelectedItem().toString();
Log.d("portfolio", portfolioChoice);
if( portfolioChoice.equals("All")){
//todo: clear second spinner
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "myURL";
//async task goes here
PortfolioGetAllBeers task = new PortfolioGetAllBeers(getActivity());
task.setOnArticleSelectedListener(this);
task.execute(url);
}
else if (portfolioChoice.equals("Brewery")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//todo: get breweries and fill spinner
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "myURL";
//async task goes here
new PortfolioGetAllBreweries(selectedItemView.getContext()).execute(url);
}
else if (portfolioChoice.equals("Style")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//construct url
String url = "http://beerportfolio.com/app_getAllYourStyles.php?u=" + userID;
//todo: async task goes here
new PortfolioGetAllStyles(selectedItemView.getContext()).execute(url);
}
else if (portfolioChoice.equals("Rating")){
LinearLayout ll = (LinearLayout) theLayout.findViewById(R.id.addSpinnerLayout);
ll.removeAllViews();
LayoutInflater inflater = (LayoutInflater)selectedItemView.getContext().getSystemService(selectedItemView.getContext().LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.addspinner_layout, null); // inflate addspinner
Spinner sp = (Spinner) v.findViewById(R.id.portfolioSpinner2); //portfolioSpinner2
ll.addView(v); // add the view to the linear layout
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
//make array
//make array list for beer
final List<String> tasteList = new ArrayList<String>();
tasteList.add("1");
tasteList.add("2");
tasteList.add("3");
tasteList.add("4");
tasteList.add("5");
// Selection of the spinner
Spinner spinner = (Spinner) theLayout.findViewById(R.id.portfolioSpinner2);
// Application of the Array to the Spinner
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(selectedItemView.getContext(), android.R.layout.simple_spinner_item,tasteList );
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
spinner.setAdapter(spinnerArrayAdapter);
//todo: add on select for spinner 2
//add on item selected
final Spinner portfolioType = (Spinner) theLayout.findViewById(R.id.portfolioSpinner2);
portfolioType.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
String portfolioChoice = portfolioType.getSelectedItem().toString();
//Toast.makeText(((Activity) c).getApplicationContext(), portfolioChoice, Toast.LENGTH_LONG).show();
final ListView lv = (ListView) theLayout.findViewById(R.id.allYourBeersList);
lv.setAdapter(null);
//get brewery beers
//get userID
//get user data
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(selectedItemView.getContext());
String userID = prefs.getString("userID", null);
try {
portfolioChoice = URLEncoder.encode(portfolioChoice, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
//construct url
String url = "myURL2";
Log.d("portfolio" , url);
//async task goes here
new PortfolioGetAllBeers(selectedItemView.getContext()).execute(url);
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// do nothing
}
});
}
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// do nothing
}
});
// Inflate the layout for this fragment
return theLayout;
}
@Override
public void onArticleSelected(String bID, String brewery){
//code to execute on click
Fragment Fragment_one;
FragmentManager man= getFragmentManager();
FragmentTransaction tran = man.beginTransaction();
Fragment_one = new BeerPage();
final Bundle bundle = new Bundle();
bundle.putString("beerIDSent", bID);
bundle.putString("breweryIDSent", brewery);
Fragment_one.setArguments(bundle);
tran.replace(R.id.main, Fragment_one);//tran.
tran.addToBackStack(null);
tran.commit();
}
}
答案 0 :(得分：3)
快速解决方法是简单地更改此行
task.setOnArticleSelectedListener（本）;
到
task.setOnArticleSelectedListener（Portfolio.this）;
说明：
使用行
实例化AdapterView.OnItemSelectedListener的内联定义portfolioType.setOnItemSelectedListener（new AdapterView.OnItemSelectedListener（）{...}
因此，当您调用setOnArticleSelectedListener（）时，您正在此内联类定义中执行此操作。因此，编译器不将“this”理解为Portfolio的当前实例，而是将其视为AdapterView.OnItemSelectedListener的当前实例。但是，内联定义可以访问封闭的Portfolio类及其成员。使用'Portfolio.this'，你告诉编译器使用这个封闭类的当前实例。
答案 1 :(得分：0)
PortfolioGetAllBeers任务的实现有一个setOnArticleSelectedListener()方法，它以OnArticleSelectedListener个实例作为参数。
Howerver，在生成错误的行中，您传递的是AdapterView.OnItemSelectedListener类型的对象：
以下是您要创建此类型的侦听器的行：
portfolioType.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { ...
然后在这个范围内你打电话：
PortfolioGetAllBeers task = new PortfolioGetAllBeers(getActivity());
task.setOnArticleSelectedListener(this);
在此范围内，this引用AdapterView.OnItemSelectedListener对象，这不是您的任务所期望的。根据您的代码，您似乎希望您的任务回调到Portfolio片段，因为它是实现侦听器接口的回调方法的那个。
因此，向编译器表明您希望this表示Portfolio实例的方法是这样写：
task.setOnArticleSelectedListener(Portfolio.this);
现在，您正在传递正确的对象实例。