MainActivity.java

package com.example.listycity;

import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;


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

import java.util.ArrayList;
import java.util.Arrays;

public class MainActivity extends AppCompatActivity {

    ListView cityList;
    ArrayAdapter<String> cityAdapter;
    ArrayList<String> dataList;
    EditText inputCity;
    Button addButton, deleteButton;

    int selectedPosition = -1; // Tracks selection

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        EdgeToEdge.enable(this);
        setContentView(R.layout.activity_main);

        cityList = findViewById(R.id.city_list);

        String []cities = {"Edm","Van","Vic","Tor","Tok","Syd","NYC","Del","Ber","Lon"};

        dataList = new ArrayList<>();
        dataList.addAll(Arrays.asList(cities));

        cityAdapter = new ArrayAdapter<>(this, R.layout.content, R.id.content_view, dataList);
        cityList.setAdapter(cityAdapter);

        addButton = findViewById(R.id.add_button);
        inputCity = findViewById(R.id.input_city);
        deleteButton = findViewById(R.id.delete_button);

        // Tap to select city
        cityList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                selectedPosition = position;
                String city = dataList.get(position);
                Toast.makeText(MainActivity.this, "Selected: " + city, Toast.LENGTH_SHORT).show();
            }
        });

        // Add a city
        addButton.setOnClickListener(v -> {
            String city = inputCity.getText().toString().trim();
            if (!city.isEmpty()) {
                dataList.add(city);
                cityAdapter.notifyDataSetChanged();
                inputCity.setText("");
            }
        });

        // Delete selected city
        deleteButton.setOnClickListener(v -> {
            if (selectedPosition != -1) {
                String city = dataList.get(selectedPosition);
                dataList.remove(selectedPosition);
                cityAdapter.notifyDataSetChanged();
                Toast.makeText(MainActivity.this, "Deleted: " + city, Toast.LENGTH_SHORT).show();
                selectedPosition = -1; // reset selection
            } else {
                Toast.makeText(MainActivity.this, "No city selected", Toast.LENGTH_SHORT).show();
            }
        });

        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main), (v, insets) -> {
            Insets systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars());
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
            return insets;
        });
    }
}