moveCamera with CameraUpdateFactory.newLatLngBounds crashes

I'm making use of the new Android Google Maps API.

I create an activity which includes a MapFragment. In the activity onResume I set the markers into the GoogleMap object and then define a bounding box for the map which includes all of the markers.

This is using the following pseudo code:

LatLngBounds.Builder builder = new LatLngBounds.Builder();
while(data) {
   LatLng latlng = getPosition();
   builder.include(latlng);
}
CameraUpdate cameraUpdate = CameraUpdateFactory
   .newLatLngBounds(builder.build(), 10);
map.moveCamera(cameraUpdate);

The call to map.moveCamera() causes my application to crash with the following stack:

Caused by: java.lang.IllegalStateException: 
    Map size should not be 0. Most likely, layout has not yet 

    at maps.am.r.b(Unknown Source)
    at maps.y.q.a(Unknown Source)
    at maps.y.au.a(Unknown Source)
    at maps.y.ae.moveCamera(Unknown Source)
    at com.google.android.gms.maps.internal.IGoogleMapDelegate$Stub
        .onTransact(IGoogleMapDelegate.java:83)
    at android.os.Binder.transact(Binder.java:310)
    at com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a
        .moveCamera(Unknown Source)
    at com.google.android.gms.maps.GoogleMap.moveCamera(Unknown Source)
    at ShowMapActivity.drawMapMarkers(ShowMapActivity.java:91)
    at ShowMapActivity.onResume(ShowMapActivity.java:58)
    at android.app.Instrumentation
        .callActivityOnResume(Instrumentation.java:1185)
    at android.app.Activity.performResume(Activity.java:5182)
    at android.app.ActivityThread
        .performResumeActivity(ActivityThread.java:2732)

If - instead of the newLatLngBounds() factory method I use newLatLngZoom() method then the same trap does not occur.

Is the onResume the best place to draw the markers onto the GoogleMap object or should I be drawing the markers and setting the camera position somewhere else?

Solution 1:

You can use simple newLatLngBounds method in OnCameraChangeListener. All will be working perfectly and you don't need to calculate screen size. This event occurs after map size calculation (as I understand).

Example:

map.setOnCameraChangeListener(new OnCameraChangeListener() {

    @Override
    public void onCameraChange(CameraPosition arg0) {
        // Move camera.
        map.moveCamera(CameraUpdateFactory.newLatLngBounds(builder.build(), 10));
        // Remove listener to prevent position reset on camera move.
        map.setOnCameraChangeListener(null);
    }
});

Solution 2:

Those answers are just fine, but I would go for a different approach, a simpler one. If the method only works after the map is layed out, just wait for it:

map.setOnMapLoadedCallback(new GoogleMap.OnMapLoadedCallback() {
    @Override
    public void onMapLoaded() {
        map.moveCamera(CameraUpdateFactory.newLatLngBounds(bounds, 30));
    }
});

Solution 3:

OK I worked this out. As documented here that API can't be used pre-layout.

The correct API to use is described as:

Note: Only use the simpler method newLatLngBounds(boundary, padding) to generate a CameraUpdate if it is going to be used to move the camera after the map has undergone layout. During layout, the API calculates the display boundaries of the map which are needed to correctly project the bounding box. In comparison, you can use the CameraUpdate returned by the more complex method newLatLngBounds(boundary, width, height, padding) at any time, even before the map has undergone layout, because the API calculates the display boundaries from the arguments that you pass.

To fix the problem I calculated my screen size and provided the width and height to

public static CameraUpdate newLatLngBounds(
    LatLngBounds bounds, int width, int height, int padding)

This then allowed me to specify the bounding box pre-layout.

Solution 4:

The solution is simpler than that....

// Pan to see all markers in view.
try {
    this.gmap.moveCamera(CameraUpdateFactory.newLatLngBounds(bounds, 50));
} catch (IllegalStateException e) {
    // layout not yet initialized
    final View mapView = getFragmentManager()
       .findFragmentById(R.id.map).getView();
    if (mapView.getViewTreeObserver().isAlive()) {
        mapView.getViewTreeObserver().addOnGlobalLayoutListener(
        new OnGlobalLayoutListener() {
            @SuppressWarnings("deprecation")
            @SuppressLint("NewApi")
            // We check which build version we are using.
            @Override
            public void onGlobalLayout() {
                if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
                    mapView.getViewTreeObserver()
                        .removeGlobalOnLayoutListener(this);
                } else {
                    mapView.getViewTreeObserver()
                        .removeOnGlobalLayoutListener(this);
                }
                gmap.moveCamera(CameraUpdateFactory.newLatLngBounds(bounds, 50));
            }
        });
    }
}

Catch IllegalStateException and use the global listener on the view instead. Setting the bound size in advance (pre-layout) using the other methods means you have to compute the size of THE VIEW, not the screen device. They only match if you go full screen with your map and do not use fragments.

Solution 5:

This is my fix, just wait untill the map is loaded in that case.

final int padding = getResources().getDimensionPixelSize(R.dimen.spacing);    

try {
    mMap.animateCamera(CameraUpdateFactory.newLatLngBounds(pCameraBounds, padding));
} catch (IllegalStateException ise) {

    mMap.setOnMapLoadedCallback(new GoogleMap.OnMapLoadedCallback() {

        @Override
        public void onMapLoaded() {
            mMap.animateCamera(CameraUpdateFactory.newLatLngBounds(pCameraBounds, padding));
        }
    });
}