On tap open a listview that is hidden at first

Question

I have a map,using google maps api2 on android studio,when I tap anywhere, I want to open a listview where there would be radio buttons and other kind of stuff. I dont know how to do that,how to use intent,how to use listeners,can anyone help me? Here is the code I got so far:

public class MainActivity extends FragmentActivity implements OnMapReadyCallback,LocationListener {

private MapView mapV;
private GoogleMap map;
private GoogleMapOptions options;
private CameraUpdate camUp;
private double lat,lon;
private LatLng koordinate;
private String provider;
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
    map = fm.getMap();
    map.setMyLocationEnabled(true);
    LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
    Criteria criteria = new Criteria();
    provider = locationManager.getBestProvider(criteria, true);
    Location location = locationManager.getLastKnownLocation(provider);
    koordinate = new LatLng(location.getLatitude(),location.getLongitude());
    if(location!=null){
        onLocationChanged(location);


    }
    locationManager.requestLocationUpdates(provider, 20000, 0, this);
    CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(koordinate, 10);
    map.animateCamera(cameraUpdate);
}



public void openList(View view)
{
    Intent intent = new Intent(intent.ACTION_VIEW ,);
    ListView list = (ListView) findViewById(R.id.idList);

}

XML file:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >



<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:map="http://schemas.android.com/apk/res-auto"
    android:id="@+id/map"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    class="com.google.android.gms.maps.SupportMapFragment"/>

<ExpandableListView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/idList"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:onClick="openList"/>

Answer 1

The Intent class is usually associated with the button. When a button is clicked, the Intent class can be used to simply wake/start another activity or it can pass some data(String/int/etc) to that activity, and it can also get some data back if you want.

To simply wake another activity, you do:

Intent i = new Intent (*activity_action_name*);
startActivity(i);

For listeners, it's better to use when you have a lots of onClick. Because it's a good way to reduce data redundancy. If you just have one onClick. It's not necessary to use OnClickListener.

Example: if you have two buttons. You can do following.

//in onCreate declare some buttons
Button bt1 = (Button) findViewById(R.id.*button1_id*);
bt1.setOnClickListener(new clsOnClickListener());
Button bt2 = (Button) findViewById(R.id.*button2_id*);
bt2.setOnClickListener(new clsOnClickListener());

//You can create a class that implements OnClickListener
private class clsOnClickListener implements View.OnClickListener{
public void onClick(View v){
     if (v.getId()==R.id.button1_id{
          //do what you want
     }
     else if (v.getId()==R.id.button2_id){
         //do something else
     }
 }
}