I'm writing an application to interface with an automotive classifieds API. I want to have two windows: one where the user types in the kind of car they want, and one where the results are displayed.
My API returns a large JSON file, on the verge of roughly 40 parameters per vehicle, of which only about 20 have any interest to me. I have a custom class to store some of the data returned by the API. In the constructor for this class (called CarListing), I pass a JSONObject and do my JSON parsing inside the constructor.
This class is then invoked inside of a threaded HttpGet activity, which itself is called by the MainActivity. So, for a given search, I expect to get more than one result from the API. I am able to successfully return the custom objects to the MainActivity, but I am having issues with sending this data from the MainActivity to a SecondActivity. Eventually, I'd like to pass a HashMap to an adapter so I can use it in a custom layout I made.
Most of the responses I have seen on the Internet involve using Parcelable, but I do not believe that JSONObject (nor HashMap for that matter) are Parcelable objects. I have tried implementing this within the CarListing class, but Android Studio does not like that I pass a JSONObject as the constructor object.
So what would be the best method of making my custom object Parcelable? Should I do the JSON parsing outside of the constructor (i.e. in my HttpGet thread), and then pass all 20-25 values as parameters? I think my biggest issue is with the constructor, but I may be incorrect. Any help is appreciated, I can provide more information if necessary.
Here is the code for my custom object, CarListing:
package com.example.carsearchapp;
import android.os.Parcel;
import android.os.Parcelable;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.io.Serializable;
import java.text.NumberFormat;
import java.util.ArrayList;
import java.util.HashMap;
public class CarListing
{
/* vehicle parameters */
String make, model, trim, vin, color, condition, transmission, engine, drivetype, seller_type, seller_name, website, city, state;
int year, price, mileage, cylinders;
double distance;
ArrayList<String> images;
/* carfax parameters */
boolean one_owner, clean_title;
/* local variables that may be important */
int index;
JSONObject img_json, build, dealer;
JSONArray img_array;
public HashMap<String, String> listview_hashmap;
/* Most strings are default N/A. Most integers are default 1, or 1970 for the case of years. */
public CarListing(JSONObject input, int index)
{
try
{
this.images = new ArrayList<>();
this.index = index;
this.listview_hashmap = new HashMap<>();
if(input.has("vin")) this.vin = input.getString("vin");
else this.vin = "N/A";
if(input.has("price")) this.price = input.getInt("price");
else this.price = 1;
if(input.has("mileage")) this.mileage = input.getInt("mileage");
else this.mileage = 1;
if(input.has("vdp_url")) this.website = input.getString("vdp_url");
else this.website = "N/A";
if(input.has("carfax_1_owner")) this.one_owner = input.getBoolean("carfax_1_owner");
else this.one_owner = true;
if(input.has("carfax_clean_title")) this.clean_title = input.getBoolean("carfax_clean_title");
else this.clean_title = true;
if(input.has("exterior_color")) this.color = input.getString("exterior_color");
else this.color = "N/A";
if(input.has("seller_type")) this.seller_type = input.getString("seller_type");
else this.seller_type = "N/A";
if(input.has("inventory_type")) this.condition = input.getString("inventory_type");
else this.condition = "N/A";
if(input.has("build"))
{
this.build = input.getJSONObject("build");
if(this.build.has("year")) this.year = this.build.getInt("year");
else this.year = 1970;
if(this.build.has("make")) this.make = this.build.getString("make");
else this.make = "N/A";
if(this.build.has("model")) this.model = this.build.getString("model");
else this.model = "N/A";
if(this.build.has("trim")) this.trim = this.build.getString("trim");
else this.trim = "N/A";
if(this.build.has("transmission")) this.transmission = this.build.getString("transmission");
else this.transmission = "N/A";
if(this.build.has("drivetrain")) this.drivetype = this.build.getString("drivetrain");
else this.drivetype = "N/A";
if(this.build.has("cylinders")) this.cylinders = this.build.getInt("cylinders");
else this.cylinders = 4;
if(this.build.has("engine")) this.engine = this.build.getString("engine");
else this.engine = "N/A";
if(this.build.has("dist")) this.distance = this.build.getDouble("dist");
else this.distance = 0;
}
if(input.has("dealer"))
{
this.dealer = input.getJSONObject("dealer");
if(this.dealer.has("name")) this.seller_name = capitalizeLetters(this.dealer.getString("name"));
else this.seller_name = "N/A";
if(this.dealer.has("city")) this.city = this.dealer.getString("city");
else this.city = "N/A";
if(this.dealer.has("state")) this.state = this.dealer.getString("state");
else this.state = "N/A";
}
if(input.has("media"))
{
this.img_json = input.getJSONObject("media");
if(this.img_json.has("photo_links")) this.img_array = this.img_json.getJSONArray("photo_links");
else this.img_json = null;
int n = this.img_array.length();
for(int i=0;i<n;i++)
{
if(i >= 50) break;
else
{
this.images.add(img_array.getString(i));
}
}
}
}
catch(JSONException ex)
{
System.out.println("JSON Exception thrown");
}
}
public String capitalizeLetters(String input)
{
String[] array = input.split(" ");
String output = "";
int n = array.length;
for(int i=0;i<n;i++)
{
String cap = array[i].substring(0, 1).toUpperCase() + array[i].substring(1);
output += cap;
}
return output;
}
public void makeHashMap()
{
String vehicle_title = Integer.toString(this.year) + this.make + this.model + this.trim;
String vehicle_information = NumberFormat.getIntegerInstance().format(this.mileage) + " miles | " + this.color + " | " + this.condition + " | $" + NumberFormat.getIntegerInstance().format(this.price);
String dealer_name = this.seller_name;
String location = Double.toString(this.distance) + " mi. | " + this.city + ", " + this.state;
String first_img = this.images.get(0);
this.listview_hashmap.put("title", vehicle_title);
this.listview_hashmap.put("information", vehicle_information);
this.listview_hashmap.put("dealer", dealer_name);
this.listview_hashmap.put("distance", location);
this.listview_hashmap.put("first_image", first_img);
}
}
