我有一个使用 volley into AutoCompleteAdapter 到服务器的搜索请求，我想将我的请求结果获取到适配器中的结果过滤器中，但在从服务器获取结果之前，将 null 获取到适配器和应用程序中的结果过滤器崩溃，我该如何处理这种情况？谢谢，这是我的代码:
public class AutoCompleteAdapter extends ArrayAdapter<Company> implements Filterable {
private ArrayList<String> mData;
RequestQueue queue;
Context context ;
public AutoCompleteAdapter(Context context, int textViewResourceId) {
super(context, textViewResourceId);
mData = new ArrayList<>();
this.context = context ;
}
@Override
public int getCount() {
return mData.size();
}
@Override
public Filter getFilter() {
Filter myFilter = new Filter() {
@Override
protected FilterResults performFiltering(final CharSequence constraint) {
FilterResults filterResults = new FilterResults();
if(constraint != null) {
Log.e("constraint",constraint+"");
queue = Volley.newRequestQueue(context);
String url = "http://eteebar.com/api/main/search";
// Request a string response from the provided URL.
StringRequest jsonArrayRequest = new StringRequest(Request.Method.POST, url,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
ArrayList<Image> imagesArray;
ArrayList<Articles> articlesArray;
ArrayList<Comment> commentsArray;
ArrayList<Offer> offersArray;
try {
ArrayList<String> companies = new ArrayList<>();
JSONArray jsonArray = new JSONArray(response);
for(int i= 0 ; i < jsonArray.length(); i++){
imagesArray = new ArrayList<>();
articlesArray = new ArrayList<>();
commentsArray = new ArrayList<>();
offersArray = new ArrayList<>();
JSONObject c = jsonArray.getJSONObject(i);
JSONArray images = c.getJSONArray("images") ;
JSONArray articles = c.getJSONArray("articles") ;
JSONArray comments = c.getJSONArray("comments") ;
JSONArray offers = c.getJSONArray("offers") ;
for(int img = 0 ; img < images.length() ; img ++){
try{
JSONObject im = images.getJSONObject(img);
Image image = new Image(im.getString("id"),im.getString("company_id"),im.getString("link"),
im.getString("is_deleted"));
imagesArray.add(img,image);
}
catch (JSONException ex){
}
}
for(int art = 0 ; art < articles.length() ; art ++){
try{
JSONObject ar = articles.getJSONObject(art);
Articles article = new Articles(ar.getString("id"),ar.getString("company_id"),ar.getString("link"),ar.getString("subject"),
ar.getString("description"),ar.getString("is_active"));
articlesArray.add(art,article);
}
catch (JSONException ex){
}
}
for(int com = 0 ; com < comments.length() ; com ++){
try{
JSONObject commen = comments.getJSONObject(com);
Comment comment = new Comment(commen.getString("id"),commen.getString("comment"),commen.getString("company_id"),
commen.getString("customer_id"),commen.getString("plus_count"),commen.getString("minus_count"),commen.getString("is_active")
,commen.getString("is_deleted"),commen.getString("customer_name"));
commentsArray.add(com,comment);
}
catch (JSONException ex){
}
}
for(int off = 0 ; off < offers.length() ; off ++){
try{
JSONObject of = offers.getJSONObject(off);
Offer offer = new Offer(of.getString("id"),of.getString("customer_id"),of.getString("keyfiate_mahsoulat"),
of.getString("pasokhgouyi"),of.getString("poshtibani"),of.getString("takhassos"),of.getString("tarrahiye_basari"),of.getString("tabliqat"),
of.getString("tarefeha"),of.getString("qedmat"),of.getString("sorat"),of.getString("standard"),of.getString("peygiri"),
of.getString("bastebandi"),of.getString("website"),of.getString("amouzesh"),of.getString("berouz_boudan"),of.getString("vosate_brand"),of.getString("vabaste_be_dolat"),
of.getString("description"),of.getString("description_balance"),of.getString("is_deleted"),of.getString("customer_name"));
offersArray.add(off,offer);
}
catch (JSONException ex){
}
}
Company company = new Company(c.getString("id"),c.getString("customer_id"),c.getString("name"),c.getString("brand"),c.getString("shoar"),c.getString("email"),c.getString("website"),c.getString("employees_count"),c.getString("branchs_count"),
c.getString("tags"),c.getString("customers_count"),c.getString("product_id1"),c.getString("product_id2"),c.getString("product_id3"),c.getString("telegram"),c.getString("instagram"),
c.getString("facebook"),c.getString("linkedin"),c.getString("google"),c.getString("mazaya"),c.getString("goals"),c.getString("description"),c.getString("link"),c.getString("seen_count"),c.getString("comment_balance"),c.getString("fields_balance"),c.getString("customer_balance"),c.getString("etebar_balance"),c.getString("main_balance")
,c.getString("sharing_count"),c.getString("is_active"),c.getString("is_deleted"),c.getString("created_at_jalali"),c.getString("updated_at_jalali"),c.getString("created_at"),c.getString("updated_at"),c.getString("category_name"),c.getString("customer_name"),c.getString("product_name1"),c.getString("product_name2"),c.getString("product_name3"),imagesArray,articlesArray,commentsArray,offersArray);
companies.add(company.name);
}
Log.e("companySize:",companies.size()+"");
if(companies.size()>0){
FilterResults filter = new FilterResults();
mData = companies ;
Log.e("mData",mData.size()+" " + mData);
filter.values = mData;
filter.count = mData.size();
// Log.e("filterResult",filterResults.values+"");
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e("Volley",error.toString());
}
}) {
@Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
Log.e("searchText",constraint.toString());
if(constraint.length()>0){
params.put("key", constraint.toString());
}
params.put("offset", "0");
params.put("limit","20");
return params;
}
};
jsonArrayRequest.setTag("tag");
jsonArrayRequest.setRetryPolicy(new DefaultRetryPolicy(
400000,
DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
// Add the request to the RequestQueue.
queue.add(jsonArrayRequest);
// Now assign the values and count to the FilterResults object
}
return filterResults;
}
@Override
protected void publishResults(CharSequence contraint, FilterResults results) {
if(results != null && results.count > 0) {
notifyDataSetChanged();
}
else {
notifyDataSetInvalidated();
}
}
};
return myFilter;
}
}
最佳答案
方法performFiltering()在辅助线程中调用。您再次通过 Volley 进行异步调用。因此，performFiltering() 方法在响应到达之前返回，从而导致崩溃。您所需要做的就是阻止 performFiltering() 直到响应到达。
这可以通过Volley提供的RequestFuture来实现。
queue = Volley.newRequestQueue(context);
String url = "http://eteebar.com/api/main/search";
RequestFuture<String> future = RequestFuture.newFuture();
StringRequest request = new StringRequest(Method.POST, url, reqBody, future, future);
queue.add(request);
try {
String response = future.get(); // this is a blocking call
// write your body of onResponse() here
} catch (InterruptedException e) {
} catch (ExecutionException e) {
// if something went wrong
}
关于android - 将 volley 请求的结果使用到 AutocompleteAdapter 中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45127962/