Marker on the map disappears when orientation changes

Question

I've implmenented a simple Activity which contains two tabs. These tabs are associated with Fragments: the first one is a MapFragment, the second is a ListFragment. I overrid the onCreate method in this way:

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.path_summary);

    final ActionBar actionbar = getActionBar();
    actionbar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    actionbar.addTab(actionbar.newTab()
            .setText("Map")
            .setTabListener(new TabListener<com.google.android.gms.maps.MapFragment>(
                    this, "map", com.google.android.gms.maps.MapFragment.class)));

    actionbar.addTab(actionbar.newTab()
            .setText("List")
            .setTabListener(new TabListener<com.example.northfinder.PathListFragment>(
                    this, "list", com.example.northfinder.PathListFragment.class)));


    if (savedInstanceState != null) {
        actionbar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
    }

}

Then I need to write in the map (adding a marker), so I've override the onResume method:

protected void onResume() {
    super.onResume();

        FragmentManager fm = getFragmentManager();
        Fragment f = fm.findFragmentByTag("map");
        if(f!= null && f.isAdded())
        setUpMapIfNeeded((MapFragment)f);
    }

where setUpIfNeeded is defined below:

private static void setUpMapIfNeeded(MapFragment mMapFragment) {
    // Do a null check to confirm that we have not already instantiated the map.
    if (mMap == null) {
        mMap = mMapFragment.getMap();

    }
        if (mMap != null) {
            mMap.clear()
        mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker"));
    }
}

All works good. The marker is correctly added in the MapFragment when the Activity starts, and when I change tab and then I come back in the first tab the marker is yet visible.

I have just a problem: when orientation changes the marker disappears. Why?

see http://stackoverflow.com/questions/5123407/losing-data-when-rotate-screen — Shayan Pourvatan, Mar 06 '14 at 14:09
But when orientation changes the Activity should be recreated so both onCreate and onResume should be executed. Right? — GVillani82, Mar 06 '14 at 14:16
Uhm I think that in my question I was missing an important thing. I.e. I've declared mMap variable as static. — GVillani82, Mar 06 '14 at 14:21
Yes I was right: I have removed the static keyword from mMap variable and now it works :D — GVillani82, Mar 06 '14 at 14:22
I have partially soled the problem. Because, when I select the second tab then change orientation and then come back to the first tab the marker disappears. I solved the problem only when I'm on the first tab and I change rotation :( — GVillani82, Mar 06 '14 at 14:25

score 0 · Answer 1 · answered Mar 06 '14 at 14:47

0

I solved the problem adding this code inside the callbacks onTabSelected and onTabReselected

if(mTag.compareToIgnoreCase("map")==0)
{
    setUpMapIfNeeded((MapFragment)mFragment);
}

answered Mar 06 '14 at 14:47

GVillani82

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Marker on the map disappears when orientation changes

1 Answers1