Android Spinner setOnItemSelectedListener 不工作

Question

我在登录过程中动态制作了一个微调器。我希望能够在单击某个选项时返回微调器的值，但它似乎不起作用。

我在这里制作微调器:

public Spinner page_spinner;

protected void onCreate(Bundle savedInstanceState){
...
page_spinner = (Spinner) findViewById(R.id.page_spinner);
...
//MAKE ARRAY HERE
GraphRequest requestPage = GraphRequest.newGraphPathRequest(
    currentAccessToken,
    "/me/accounts",
    new GraphRequest.Callback() {
        @Override
        public void onCompleted(GraphResponse response) {
            JSONArray jsonArray = null;
            try {
                jsonArray = response.getJSONObject().getJSONArray("data");
                for(int i=0; i < jsonArray.length(); i++){
                JSONObject page = jsonArray.getJSONObject(i);
                String pageName = page.getString("name");
                if(!pageName.equals("")) {
                    //Push names into the array
                    pages_array.add(pageName);
                } else {
                    pages_array.clear();
                }
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }
});
Bundle pageParameters = new Bundle();
pageParameters.putString("fields", "name,access_token,picture{url}");
requestPage.setParameters(pageParameters);
requestPage.executeAsync();
...
ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(StartPage.this, android.R.layout.simple_spinner_item, pages_array);
spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
page_spinner.setAdapter(spinnerArrayAdapter);
spinnerArrayAdapter.notifyDataSetChanged();

然后我尝试在这里使用微调器:

page_spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        Log.d("***********", "THIS ");
    }
    @Override
    public void onNothingSelected(AdapterView<?> parent) {
        Log.d("***********", "THIS ");
    }
});

我从来没有得到 Log.d 或者即使我在那里做了 Toast，它也不会触发。不知道为什么会停止并且我没有收到任何错误。

有什么想法吗？

Answer 1

将微调器声明为全局变量并且没有final

然后试试这个:

page_spinner = (Spinner) findViewById(R.id.page_spinner);
...
//MAKE ARRAY HERE
GraphRequest requestPage = GraphRequest.newGraphPathRequest(
    currentAccessToken,
    "/me/accounts",
    new GraphRequest.Callback() {
        @Override
        public void onCompleted(GraphResponse response) {
            JSONArray jsonArray = null;
            try {
                jsonArray = response.getJSONObject().getJSONArray("data");
                for(int i=0; i < jsonArray.length(); i++){
                JSONObject page = jsonArray.getJSONObject(i);
                String pageName = page.getString("name");
                if(!pageName.equals("")) {
                    //Push names into the array
                    pages_array.add(pageName);
                } else {
                    pages_array.clear();
                }
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
        ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(StartPage.this, android.R.layout.simple_spinner_item, pages_array);
        spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); // The drop down view
        page_spinner.setAdapter(spinnerArrayAdapter);
        spinnerArrayAdapter.notifyDataSetChanged();
    }
});