How to keep the map marker in the center of the screen at all times? Android

Question

I am trying to find a way to center my map marker in my map fragment activity. So far, I have tried adding a marker to the center of the screen every time the map is moved i.e., the camera position is updated. But the problem with this solution is that every time a new marker gets added into the map at the center and the old one stays there so in just a couple of drags i would have like 10 markers on my screen. I tried using the clear method before adding the next marker but now the marker is just flashing too much. Here's my code:

mMap.setOnCameraChangeListener(new GoogleMap.OnCameraChangeListener() {
            @Override
            public void onCameraChange(CameraPosition cameraPosition) {
                LatLng location=mMap.getCameraPosition().target;
                MarkerOptions marker=new MarkerOptions().position(location).title("");
                mMap.clear();
                mMap.addMarker(marker);
                mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(location, 16));
            }
        });

The other solution i have found is to use a centered ImageView but the problem with that is that i want to change the icon of my marker. But when i add an image image to the image view, the center of the camera is in the green little circle in the center of this image and not the pointy end of it like i want to. Please help.

Take a look at http://stackoverflow.com/questions/36157242/pinch-to-zoom-google-map-with-out-moving-marker-in-framelayout/36287722#36287722 — antonio, Jul 12 '16 at 19:09
I am sorry but can you clarify how exactly can i use the AnchoredImageView? I added it as a java class in src/main/ directory but what now? — Rehan Yousaf, Jul 12 '16 at 19:37
Now you need to edit your layout XML as in the example and as the rest of the code on your Activity — antonio, Jul 12 '16 at 19:40

score 6 · Accepted Answer · answered Jul 12 '16 at 20:34

6

Don't use a real marker. Put the MapFragment or MapView in a layout with a fake marker image centered over it. When the location is chosen, place a real marker and hide the fake one.

If the "pointy end" of the fake marker image is not in its exact center, simply pad the image with transparent space until it is.

answered Jul 12 '16 at 20:34

Kevin Krumwiede

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hye kevin ,can you give me link of code for this explaination? :) – Shivam Sharma Sep 25 '17 at 06:53
That marker won't point to the correct location if you centered it like that. – Pedro Oliveira Jul 20 '21 at 15:42
@PedroOliveira Yes, it does. It won't point to the correct location if you *don't* center it like that. – Kevin Krumwiede Jul 20 '21 at 15:43

score 1 · Answer 2 · answered Oct 06 '16 at 21:53

Yep, actually you can use setOnCameraChangeListener. So you don't need to clear your marker every time, just set new position for it. Try this code:

map.setOnCameraChangeListener(new GoogleMap.OnCameraChangeListener() {
    @Override
    public void onCameraChange(CameraPosition cameraPosition) 
    {
        if(marker==null)
        {
            marker = map.addMarker(new MarkerOptions().position(cameraPosition.target).title("Marker")
                    .icon(BitmapDescriptorFactory.fromResource(R.mipmap.marker)));
            marker.showInfoWindow();
        }
        else
        {
            marker.setPosition(cameraPosition.target);
        }
    }
});

This should work. So, the only problem is that your marker will move to centre of the map only at the end of map dragging. To avoid this problem you can just use something like ImageView and paste it at the centre of your map Fragment. Thereafter you can use the code above with adding just:

marker.setVisible(false);

first one isn't good enough, the marker is lagging behind rather than staying fixed on the screen — arekolek, Mar 07 '23 at 09:17

score -1 · Answer 3 · answered Jul 12 '16 at 20:26

Assuming you are using Google Play Services for getting user's location call below from

@Override
    public void onConnected(Bundle connectionHint) {
        Log.i(TAG, "Connected to GoogleApiClient");

        // If the initial location was never previously requested, we use
        // FusedLocationApi.getLastLocation() to get it. If it was previously requested, we store
        // its value in the Bundle and check for it in onCreate(). We
        // do not request it again unless the user specifically requests location updates by
        // pressing
        // the Start Updates button.
        //
        // Because we cache the value of the initial location in the Bundle, it means that if the
        // user launches the activity,
        // moves to a new location, and then changes the device orientation, the original location
        // is displayed as the activity is re-created.
        if (mCurrentLocation == null) {
            mCurrentLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
            drawOnMap(new LatLng(mCurrentLocation.getLatitude(), mCurrentLocation.getLongitude()));
        }
    }

And

/**
     * Callback that fires when the location changes.
     */
    @Override
    public void onLocationChanged(Location location) {
        mCurrentLocation = location;
        if (location != null) {
            drawOnMap(new LatLng(location.getLatitude(), location.getLongitude()));
        }
    }

This will be the function to update marker on the map.

   public void drawOnMap(final LatLng location) {
        if (isFirstLocation) {
            markerCurrent = mMap.addMarker(new MarkerOptions()
                    .position(location)
                    .icon(BitmapDescriptorFactory.fromResource(R.drawable.dot)));
            isFirstLocation = false;
        } else {
            markerCurrent.setPosition(location);
        }
        CameraPosition cp = getCameraPosition(location);
        int animationDuration = 600;
        mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cp), animationDuration, null);
    }

How to keep the map marker in the center of the screen at all times? Android

3 Answers3