air_quality/app/moodle/AQActivity.java

package com.example.airquality;

import android.os.Bundle;

import android.content.Intent;
import android.os.Bundle;
import android.view.MenuInflater;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;

import org.json.JSONObject;

import java.util.HashMap;
import java.util.Map;

public class AQActivity extends AppCompatActivity {
    private static final Map<String, double[]> cityCoordinates = new HashMap<>();
    static {
        cityCoordinates.put("Subotica", new double[]{46.1, 19.6667});
        cityCoordinates.put("Novi Sad", new double[]{45.2517, 19.8369});
        cityCoordinates.put("Beograd", new double[]{44.804, 20.4651});
        cityCoordinates.put("San Francisko", new double[]{37.7749, -122.4194});
        cityCoordinates.put("Sidnej", new double[]{-33.8679, 151.2073});
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        EdgeToEdge.enable(this);
        setContentView(R.layout.activity_aqactivity);
        Toolbar toolbar = findViewById(R.id.toolbar);

        // Using toolbar as ActionBar
        setSupportActionBar(toolbar);

        // Display application icon in the toolbar
        if (getSupportActionBar() != null) {
            getSupportActionBar().setDisplayShowHomeEnabled(true);
            getSupportActionBar().setLogo(R.drawable.weather_clear_symbolic);
            getSupportActionBar().setDisplayUseLogoEnabled(true);
        }

        loadAQ();
    }
    @Override
    protected void onResume() {
        super.onResume();
        loadAQ();
    }

    public boolean onCreateOptionsMenu(android.view.Menu menu) {
        MenuInflater inflater = getMenuInflater();

        inflater.inflate(R.menu.menu_main, menu);
        return super.onCreateOptionsMenu(menu);
    }


    @Override
    public boolean onOptionsItemSelected(android.view.MenuItem item) {
        switch (item.getItemId()) {
            case R.id.menu_aq:
                Intent intentAQ = new Intent(this, AQActivity.class);
                startActivity(intentAQ);
                return true;
            case R.id.menu_settings:
                Intent intent = new Intent(this, SettingsActivity.class);
                startActivity(intent);
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
    private String getAQIDescription(int aqi) {
        switch (aqi) {
            case 1: return "Good";
            case 2: return "Fair";
            case 3: return "Moderate";
            case 4: return "Poor";
            case 5: return "Very Poor";
            default: return "Unknown";
        }
    }
    public void loadAQ(){
        String city = PreferencesManager.getCity(this);
        double[] coords = cityCoordinates.get(city);
        if (coords == null) {
            Toast.makeText(this, "Unknown city: " + city, Toast.LENGTH_SHORT).show();
            return;
        }
        String apiKey = getString(R.string.weather_api_key);
        String url = String.format(
                "https://api.openweathermap.org/data/2.5/air_pollution?lat=%.6f&lon=%.6f&appid=%s",
                coords[0], coords[1], apiKey
        );

        RequestQueue queue = Volley.newRequestQueue(this);
        JsonObjectRequest request = new JsonObjectRequest(
                Request.Method.GET,
                url,
                null,
                new Response.Listener<JSONObject>() {
                    @Override
                    public void onResponse(JSONObject response) {
                        try {
                            // Get JSON fields
                            JSONObject listItem = response.getJSONArray("list").getJSONObject(0);
                            int aqi = listItem.getJSONObject("main").getInt("aqi");

                            View rootLayout = findViewById(R.id.main);

                            int colorResId;
                            switch (aqi) {
                                case 1:
                                    colorResId = R.color.aqi_good;
                                    break;
                                case 2:
                                    colorResId = R.color.aqi_fair;
                                    break;
                                case 3:
                                    colorResId = R.color.aqi_moderate;
                                    break;
                                case 4:
                                    colorResId = R.color.aqi_poor;
                                    break;
                                case 5:
                                    colorResId = R.color.aqi_very_poor;
                                    break;
                                default:
                                    colorResId = android.R.color.background_light;
                            }

                            rootLayout.setBackgroundColor(getResources().getColor(colorResId));

                            JSONObject components = listItem.getJSONObject("components");
                            double pm25 = components.getDouble("pm2_5");
                            double pm10 = components.getDouble("pm10");
                            double o3 = components.getDouble("o3");
                            double co = components.getDouble("co");
                            double no2 = components.getDouble("no2");


                            TextView tvCity = findViewById(R.id.tvCity);
                            TextView tvAQ = findViewById(R.id.tvAQ);
                            TextView tvComponents = findViewById(R.id.tvComponents);


                            String city = PreferencesManager.getCity(AQActivity.this);


                            tvCity.setText("City: " + city);
                            tvAQ.setText("AQI Index: " + aqi + " (" + getAQIDescription(aqi) + ")");
                            tvComponents.setText(
                                    String.format("PM2.5: %.2f µg/m³\nPM10: %.2f µg/m³\nO₃: %.2f ppb\nCO: %.2f ppm\nNO₂: %.2f ppb",
                                            pm25, pm10, o3, co, no2)
                            );

                        } catch (Exception e) {
                            e.printStackTrace();
                            Toast.makeText(AQActivity.this, "Failed to parse air data", Toast.LENGTH_SHORT).show();
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Toast.makeText(AQActivity.this, "Failed to load air pollution data", Toast.LENGTH_SHORT).show();
                        error.printStackTrace();
                    }
                }
        );

        queue.add(request);

    }
}