Google maps in an actionbarsherlock tab

Question

I am trying to get google maps v2 working in my app. I have seen several examples showing how you can open up SupportMapFragment inside an activity. The idea being that your activity will call setContentView(R.layout.map_layout); where map_layout.xml links to the fragment with the lines:

android:name="com.google.android.gms.maps.SupportMapFragment"
        xmlns:map="http://schemas.android.com/apk/res-auto"

The "name=" line effectively says that "this layout is to be controlled by a fragment of type 'SupportMapFragment'".

My complication is that I am attempting to get the map to appear in an activity with tabs (implemented with actionbarsherlock). This means that whatever fragment corresponds to a tab selection must implement a TabListener. But SupportMapFragment doesn't. So now presumably I need to create a new fragment like so:

public class MyMapFragmentWithTabListener extends SupportMapFragment implements TabListener
{

But now I have got all confused about how to write the contents of MapFragmentWithTabListener in particular onCreateView... should I be inflating some layout? Surely I can't be inflating exactly the same map_layout.xml from the examples because that already declares that it is controlled by SupportMapFragment, whereas in this implementation it should be controlled by MyMapFragmentWithTabListener - do I need a slightly different xml file to inflate (if so, what should it look like?) - or should I be creating my view programatically?

Answer 1

I've done this in quite a few applications now. Instead of extending SupportMapFragment, you just create your own MapFragment. You can have your own layout, with a MapView view inside of it. The key is to route the lifecycle events of the Fragment to the MapView, and bobs your uncle.

Heres some example code:

MapFragment

package com.example.testapplication;

import java.util.concurrent.TimeUnit;

import com.google.android.gms.common.GooglePlayServicesNotAvailableException;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.MapsInitializer;


public class TestMapFragment extends Fragment {

    private MapView mMapView;

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.home_fragment, container, false);

        mMapView = (MapView) view.findViewById(R.id.mapview);

        // inflat and return the layout
        mMapView.onCreate(savedInstanceState);
        mMapView.onResume();// needed to get the map to display immediately

        try {
            MapsInitializer.initialize(getActivity());
        } catch (GooglePlayServicesNotAvailableException e) {
            e.printStackTrace();
        }
        GoogleMap googleMap = mMapView.getMap();
        googleMap.getUiSettings().setMyLocationButtonEnabled(true);
        return view;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRetainInstance(true);
    }

    /*
     * Using a mapview in a fragment requires you to 'route'
     * the lifecycle events of the fragment to the mapview
     */
    @Override
    public void onResume() {
        super.onResume();
        if (null != mMapView)
            mMapView.onResume();
    }

    @Override
    public void onPause() {
        super.onPause();
        if (null != mMapView)
            mMapView.onPause();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (null != mMapView)
            mMapView.onDestroy();
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        if (null != mMapView)
            mMapView.onSaveInstanceState(outState);
    }

    @Override
    public void onLowMemory() {
        super.onLowMemory();
        if (null != mMapView)
            mMapView.onLowMemory();
    }
}

And the layout:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:map="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.google.android.gms.maps.MapView
        android:id="@+id/mapview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        map:uiZoomControls="false" />
</RelativeLayout>