AsyncTask not working with arrays (android) - android

I want AsyncTask to download multiple files that i get as an array.
Using this code the AsyncTask only works once and ignore the rest of array.
private class DownloadFiles extends AsyncTask<String[], Integer, String> {
#Override
protected String doInBackground(String[]... sUrl) {
for (int p = 0; p < sUrl.length; p++) {
for (int i=0;i<sUrl[p].length;i++) {
getFileToDown(sUrl[p][i]);
}
}
For example i want to send more than array:
downloadFiles.execute(databasesArray,imagesArray,etc);

You really need not declare String[] as generic parameter, but just a String:
AsyncTask<String, Integer, String>
doInBackground(String... sUrl) by default expects an array of type parameter.
Also, ... is called varargs, and it represents an array of optional arguments.

Related

how to add multiple lines which are an array of the same parameter in retrofit?

I want to pass an array of the same element, but i want them to be passed as new fields. I want to do something like:
#POST("/api/userInfo/changeProfileData/")
void updateProfile(
#Field("userInfoProfile[languages][0]") String language1,
#Field("userInfoProfile[languages][1]") String language2,
Callback<BaseModel<StateModel>> callback);
But the problem is that i don't know the number of elements so i cannot do like above.
I tried to pass a list:
#Field("userInfoProfile[languages]") List<String> languages
but the value is not valid because i need fields with their index (userInfoProfile[languages][0]).
Use FieldMap to make field association more dynamic.
Update your interface to:
void updateProfile(
#FieldMap Map<String, String> languages,
Callback<BaseModel<StateModel>> callback);
Method that will build FieldMap out of your list
private Map<String, String> buildFieldMap(List<String> data){
Map<String, String> map = new HashMap<String, String>();
String fieldName = "userInfoProfile[languages][%d]"
for(int i = 0; i < data.size(); i++){
map.put(String.format(fieldName, i), data.get(i));
}
return map;
}

Parsing JSON then adding multiple strings to an ArrayList

Currently working on an app that takes results from a search, parses the JSON object returned, and then adds the resulting pieces into a few ArrayLists within a class created called VenueList.
Here is the method that receives the results from the service and parses the JSON:
private static List<String> getResultsFromJson(String json) {
ArrayList<String> resultList = new ArrayList<String>();
try {
JSONObject resultsWrapper = (JSONObject) new JSONTokener(json).nextValue();
JSONArray results = resultsWrapper.getJSONArray("results");
for (int i = 0; i < results.length(); i++) {
JSONObject result = results.getJSONObject(i);
resultList.add(result.getString("text"));
}
}
catch (JSONException e) {
Log.e(TAG, "Failed to parse JSON.", e);
}
return resultList;
}
What results of this becomes a List variable call mResults (to clarify: mResults = getResultsFromJson(restResult);. That is then used, among other places, in the following loop that puts the results into an ArrayAdapter that is used for displaying them in a ListFragment:
for (String result : mResults) {
VenueList.addVenue(result, "HELLO WORLD");
adapter.add(result);
}
I also add the result to a class called VenueList that manages the results and makes them accessible for multiple views. It essentially just holds multiple ArrayLists that hold different types of details for each venue returned in the search. The method I use to add a venue to VenueList is below (and you can see it used in the for loop above):
public static void addVenue(String name, String geo) {
venueNames.add(name);
venueGeos.add(geo);
}
I want the addVenue method to be able to take multiple arguments and update the VenueList class. Yet, when I call the addVenue method in the for loop, I can only pass it String result (from the parameters of the loop) and can't figure out how to pass it a second argument (which should also come from the JSON parsed by getResultsFromJson) so I've used "HELLO WORLD" as a placeholder for now.
I realize getResultsFromJson only has one list returned. I need to be able to take multiple elements from the JSON object that I parse, and then add them to VenueList in the right order.
So my questions are:
1) Given the getResultsFromJson method and the for loop, how can I use the addVenue() method as designed? How do I parse multiple elements from the JSON, and then add them to the VenueList at the same time? I plan on adding more arguments to it later on, but I assume if I can make it work with two, I can make it work with four or five.
2) If that's not possible, how should the getResultsFromJson, the for loop, and the addVenue method be redesigned to work properly together?
Please let me know if you need more detail or code - happy to provide. Thank you!
EDIT - Full VenueList class:
public class VenueList {
private static ArrayList<String> venueNames;
private static ArrayList<String> venueGeos;
public VenueList() {
venueNames = new ArrayList<String>();
venueGeos = new ArrayList<String>();
}
public static void addVenue(String name, String geo) {
venueNames.add(name);
venueGeos.add(geo);
}
public static String getVenueName(int position) {
return venueNames.get(position);
}
public static String getVenueGeo(int position) {
return venueGeos.get(position);
}
public static void clearList() {
venueNames.clear();
venueGeos.clear();
}
}
Clarification: I will have additional ArrayLists for each element of data that I want to store about a venue (phone number, address, etc etc)
1) I don't think methods getResultsFromJson(String json) and addVenue(String name, String geo) fit your needs.
2) I would consider rewriting method getResultsFromJson(String json) to something like this:
private static SortedMap<Integer, List<String>> getResultsFromJson(String json) {
Map<Integer, String> resultMap = new TreeMap<Integer, String>();
//...
return resultMap;
}
where the number of keys of your map should be equal to the number of objects you're extracting info, and each one of them will properly have their own list of items just in the right order you extract them.
With this approach you can certainly change your logic to something like this:
// grab your retuned map and get an entrySet, the just iterate trough it
SortedMap<Integer, String> result = returnedMap.entrySet();
for (Entry<Integer, String> result : entrySet) {
Integer key = result.getKey(); // use it if you need it
List<String> yourDesiredItems = result.getValue(); // explicitly shown to know how to get it
VenueList.addVenue(yourDesiredItems);
}
public static void addVenue(List<String> yourDesiredItems) {
// refactor here to iterate the items trough the list and save properly
//....
}
EDIT -- as you wish to avoid the go-between map i'm assuming you need nothing to return from the method
First i'm providing you with a solution to your requirements, then i'll provide you with some tips cause i see some things that could smplify your design.
To save VenueList things directly from getResultsFromJSON do something like this:
private static void getResultsFromJson(String json) {
try {
JSONObject resultsWrapper = (JSONObject) new JSONTokener(json).nextValue();
JSONArray results = resultsWrapper.getJSONArray("results");
for (int i = 0; i < results.length(); i++) {
JSONObject result = results.getJSONObject(i);
//FOR EXAMPLE HERE IS WHERE YOU NEED TO EXTRACT INFO
String name = result.getString("name");
String geo = result.getString("geo");
// and then...
VenueList.addVenue(name, geo, ..., etc);
}
} catch (JSONException e) {
Log.e(TAG, "Failed to parse JSON.", e);
}
}
This implies that your addVenue method should know receive all params needed; as you can see this is just a way (that you can consider a workaround to your needs), however as i don't know all requirements that lead you to code this model, i will point to a few things you might consider:
1. If there's a reason for VenueList class to use everything static, consider doing this:
static{
venueNames = new ArrayList<String>();
venueGeos = new ArrayList<String>();
//....
}
private VenueList(){
}
This way you won't need to get an instance every time and also will avoid null pointer exceptions when doing VenueList.addVenue(...) without previous instantiation.
2. Instead of having an ArrayList for every characteristic in VenueList class consider defining a model object for a Venue like this:
public class Venue{
String name;
String geo;
//... etc
public Venue(){
}
// ... getters & setters
}
then if you need that VenueList class you will just have a list o Venue objects (List<Venue>), this means that instead of calling the method addVenue, you will first create a brand new instance of Venue class and will call the setter method of each characteristic, as an example of the refactored for loop from the workaround i provided you you'd be using something like this:
List<Venue> myListOfVenues = new ArrayList<Venue>();
for (int i = 0; i < results.length(); i++) {
JSONObject result = results.getJSONObject(i);
// THIS WOULD REMAIN THE SAME TO EXTRACT INFO
String name = result.getString("name");
String geo = result.getString("geo");
// and then instead of calling VenueList.addVenue(name, geo, ..., etc)...
Venue v = new Venue();
v.setName(name);
v.setGeo(geo);
// ...etc
myListOfVenues.add(v);
}
// Once you're done, set that List to VenueList class
VenueList.setVenueList(myListOfVenues);
So VenueList class would now have a single property List<Venue> venueList; and would suffer minor tweeks on methods getVenueName, etc... and everything would be more readable... i hope this helps you to get another approach to solve your problem, if i still don't make my point let me know and i'll try to help you out...

Pulling data from a remote mySQL database, using AsyncTask; only displaying very last table row

As the title says really. I have two columns. I want to put them into textviews so I did it. However only the bottom two results, one from each column gets shown. Very odd. Here is my code: http://pastebin.com/qNgfHfT3
The parsing/onPostExecute is towards the bottom where the issue is.
One thing to note: The logs labeled "work" & "dontwork" show all my results, however the logs in the onPostExecute (Google & Google1) only show the last result so I presume the error is in the transfer from parsing to displaying.
Would really appreciate any help here. Thanks.
If you are receiving a JSON response I'd suggest you to parse it by using Gson. It's strongly recommendable as long as you can parse the whole thing in a pair of lines.
Note that creating a proper object it is as easy as doing the following:
YourObject object = gson.fromJson(responseReader, YourObject.class);
or even if you are retrieving a list of items:
Type listType = new TypeToken<List<YourObject>>() {}.getType();
List<YourObject> objects = gson.fromJson(responseReader, listType);
Here's an example that fits exactly your needs
After the process is done you'll have your object (or list of objects) available in an accesible variable.
EDIT:
First your Asynctask should have the following params:
public class HttpTask extends AsyncTask<Void, Void, ArrayList<Driver>> {
and your doInBackground method will need to pass that array to your onPostExecute:
#Override
protected ArrayList<Driver> doInBackground(Void... params) {
For the rest, I take it when the JSon parsing starts.
//PARSING JSON DATA
try {
JSONObject json_data;
Driver d;
jArray = new JSONArray(result);
int l = jArray.length();
if(l>0){
ArrayList<Driver> drivers = newArrayListList<Driver>();
for (int i = 0; i < l; i++) {
json_data = jArray.getJSONObject(i);
d = new Driver(json_data.optString("Driver_full_name"), json_data.optString("Drives_for"));
drivers.add(d);
Log.i("work", returnString);
Log.i("dontwork", somethingelse);
}
} catch (JSONException e1) {
Log.d("DB", "Error somewhere");
CurrentSeasonDrivers_DriverName.this.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(CurrentSeasonDrivers_DriversName, "Could not parse data so shut up", Toast.LENGTH_LONG).show();
}
});
}
return drivers;
}
protected void onPostExecute(ArrayList<Drivers>... drivers) {
Log.i("Google", returnString);
Log.i("Google1", somethingelse);
String firstDriverName = drivers.get(0).name;
String firstDriverDrivesFor = drivers.get(0).drivesfor;
String secondDriverName = drivers.get(1).name;
TextView drivername = (TextView) findViewById(R.id.DriverName);
drivername.setText(firstDriverName);
TextView drivesfor = (TextView) findViewById(R.id.DrivesFor);
drivesfor.setText(firstDriverDrivesFor);
}
With this and an object for your driver will complete the circle.
public class Driver{
public String name;
public String drivesfor;
public Driver(String _name, String _drivesfor){
name = _name;
drivesfor = _drivesfor;
}
}
I guess you can take over from here.
Let me know about your progress.

Trying to use AsyncTask do download some image files

I have list of files stored inside arraylist that I need to download in background thread. My initial thought is that AsyncTask should be up for that task. But, I have a problem, I don't know how to supply my list to doInBackground method.
My arraylist is defined as
private ArrayList<String> FilesToDownload = new ArrayList<String>();
My DownloadFiles subclass (the way it is written now) should be called with:
new DownloadFiles().execute(url1, url2, url3, etc.);
This is not suitable for me since I never know how many urls I will have. It is pretty much changing from case to case. So, I would like somehow to pass my arraylist to doInBackground method.
I tried to convert to array with toArray():
new DownloadFiles().execute(FilesToDownload.toArray());
But, eclipse tells me that execute is not applicable for argument Object[].
Suggestion was to cast to URL[], but when I tried that I got illegal casting error and app crashed.
It seems that doInBackground has to be implemented with parameters in varargs type (URL... urls).
Any ideas how to solve my problem? Thanks.
class DownloadFiles extends AsyncTask<URL, Integer, Long> {
protected Long doInBackground(URL... urls) {
int count = urls.length;
long totalSize = 0;
for (int i = 0; i < count; i++) {
Log.d("Evento", "&&&& downloading: " + FilesToDownload.get(i).toString());
// totalSize += Downloader.downloadFile(urls[i]);
// publishProgress((int) ((i / (float) count) * 100));
}
return totalSize;
}
protected void onProgressUpdate(Integer... progress) {
//setProgressPercent(progress[0]);
}
protected void onPostExecute(Long result) {
//showDialog("Downloaded " + result + " bytes");
}
}
Your AsyncTask is declared with a param type of URL, but you're trying to pass String (or ArrayList) objects. Either prepare an Array of URL objects in the calling program or modify DownloadFiles to accept String instead of URL parameters and convert each String to a URL in the execute() method.
Better yet, since you are accessing FilesToDownload from within execute(), you don't need to pass anything to execute() and you could declare the first generic parameter of DownloadFiles as Void.

how to be easier to analyse the json

i want to analyse the json just like:
[{"id":"ssq","name":"双色球","term":"2010092","date":"2010-08-12 19:15","numbers":{"normal":"3,13,19,27,28,30","special":"2"},"jackpot":"30000000"},{"id":"3d","name":"3D","term":"2010216","date":"2010-08-12 19:55","numbers":{"normal":"6,8,8"},"jackpot":"-"},{"id":"qlc","name":"七乐彩","term":"2010093","date":"2010-08-11 20:45","numbers":{"normal":"08,09,10,11,16,21,27","special":"26"},"jackpot":"0"},{"id":"dfljy","name":"东方6+1","term":"2010093","date":"2010-08-14 18:30","numbers":{"normal":"4,1,3,9,7,2","special":"羊"},"jackpot":"12866531"},{"id":"swxw","name":"15选5","term":"2010217","date":"2010-08-12 18:45","numbers":{"normal":"1,3,5,13,15"},"jackpot":"5693612"},{"id":"ssl","name":"时时乐","term":"20100811-23","date":"2010-08-12 10:27","numbers":{"normal":"6,7,1"},"jackpot":"-"},{"id":"klsf","name":"快乐十分","term":"201021649","date":"2010-08-11 22:00","numbers":{"normal":"5,11,12,14,20"},"jackpot":"-"},{"id":"klsc","name":"快乐双彩","term":"2010215","date":"2010-08-10 21:25","numbers":{"normal":"12,23,10,15,7,3","special":"11"} ,"jackpot":"198059"}]
i want to gain all of them,but the data is so many,so whether i need to create 8 kinds of class to store the data,so to be easier to use.thanks!
To add to cfei's response, one thing that I've done when processing JSON responses from Flickr, is create a new class particularly for that type of object.
So for yours, just playing it by ear, something like the below:
public class Lottery() {
private JSONObject json;
private String id;
private String name;
private String term;
private String date;
private String norm_numbers;
private String spec_numbers;
private String jackpot;
public Lottery(JSONObject json) {
this.json = json;
}
public void setId()
{
try {
id = json.getString("id");
} catch (JSONException e) {
id = "";
}
}
//additional getters and setters, etc.
}
This way, you can make an array of objects, and access the fields like so:
//...get a JSONObject from the array...
Lottery lottery = new Lottery(json);
Log.v("ID", lottery.id);
Log.v("Name", lottery.name);
and so on.
Do you mean that you want to iterate through each of the eight JSONObjects in this JSONArray? You need to create a JSONArray object with the input string you posed above (let's call it "response", as used below) and then iterate through the array to get each JSONObject it contains. For example:
JSONArray array = new JSONArray(response);
for(int i = 0; i < array.length(); i++) {
JSONObject obj = array.getJSONObject(i);
// do something with obj
// example: to get the id for a particular object, use obj.getString("id")
Log.i("Example", "the id is"+obj.getString("id"));
}

Categories

Resources