Picasso image loading issue in GoogleMap.InfoWindowAdapter

问题

I am using Google Maps Api and want to show an image inside InfoWindow when clicking of a Marker. I implemented it but there is a problem about Picasso. When I click a marker, infoWindow is shown up and imageView shows placeholder image. If I click same marker one more time, Picasso loads the image succesfully. I have to click twice, it is so weird.

Screenshots for better understanding:

First click on the marker:

When I click again:

There is my codes below:

InfoWindowAdapter (Picasso loading here)

mMap.setInfoWindowAdapter(new GoogleMap.InfoWindowAdapter() {
        @Override
        public View getInfoWindow(Marker marker) {
            return null;
        }

        @Override
        public View getInfoContents(Marker marker) {
            View myContentsView = getLayoutInflater().inflate(R.layout.map_info_content, null);
            ImageView imageView = (ImageView) myContentsView.findViewById(R.id.imgView_map_info_content);
            Picasso.with(MainActivity.this)
                    .load(marker.getSnippet())
                    .placeholder(R.drawable.ic_placeholder)
                    .into(imageView);
            return myContentsView;
        }
    });

Setting markers (using snippet to pass image url)

for (MediaFeedData item : mItemList) {
        LatLng position = new LatLng(item.getLocation().getLatitude(),
                item.getLocation().getLongitude());
        mMap.addMarker(new MarkerOptions()
                .snippet(item.getImages().getLowResolution().getImageUrl())
                .icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_point))
                .position(position));
    }

InfoWindow layout xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">

<ImageView
    android:id="@+id/imgView_map_info_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

</LinearLayout>

回答1:

I solved it. Actually, this post is the answer. But I want to explain how to do it and give more details to solve this problem in my situation.

When showing an InfoWindow, it is captured of the layout. It means that InfoWindows are not dynamic, they are just a picture, a snapshot. That's why, we have to refresh the InfoWindow after image loaded successfully. We can use Picasso's Callback to do it.

I changed my codes like below:

My new InfoWindowAdapter Class:

public class MapInfoWindowAdapter implements GoogleMap.InfoWindowAdapter {
    private final Hashtable<String, Boolean> markerSet;
    private Context context;
    private View myContentsView;

    public MapInfoWindowAdapter(Context context, Hashtable<String, Boolean> markerSet) {
        this.context = context;
        this.markerSet = markerSet;
    }

    @Override
    public View getInfoWindow(Marker marker) {
        return null;
    }

    @Override
    public View getInfoContents(Marker marker) {
        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        myContentsView = inflater.inflate(R.layout.map_info_content, null);
        ImageView imageView = (ImageView) myContentsView.findViewById(R.id.imgView_map_info_content);
        boolean isImageLoaded = markerSet.get(marker.getId());
        if (isImageLoaded) {
            Picasso.with(context)
                    .load(marker.getSnippet())
                    .placeholder(R.drawable.ic_placeholder)
                    .into(imageView);
        } else {
            isImageLoaded = true;
            markerSet.put(marker.getId(), isImageLoaded);
            Picasso.with(context)
                    .load(marker.getSnippet())
                    .placeholder(R.drawable.ic_placeholder)
                    .into(imageView, new InfoWindowRefresher(marker));
        }

        return myContentsView;
    }
}

I passed to it a markers set, it holds marker ids and a boolean to determine image for that marker is loaded or not. I am checking this to select which Picasso code should run. If I don't do this, it will be recursion.

InfoWindowRefresher:

public class InfoWindowRefresher implements Callback {
    private Marker markerToRefresh;

    public InfoWindowRefresher(Marker markerToRefresh) {
        this.markerToRefresh = markerToRefresh;
    }

    @Override
    public void onSuccess() {
        markerToRefresh.showInfoWindow();
    }

    @Override
    public void onError() {}
}

Setting markers (using snippet to pass image url):

Hashtable<String, Boolean> markerSet = new Hashtable<>();
for (MediaFeedData item : mItemList) {
    LatLng position = new LatLng(item.getLocation().getLatitude(),
            item.getLocation().getLongitude());
    MarkerOptions markerOptions = new MarkerOptions()
            .snippet(item.getImages().getLowResolution().getImageUrl())
            .icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_point))
            .position(position);
    Marker marker = mMap.addMarker(markerOptions);
    markerSet.put(marker.getId(), false);
}

mMap.setInfoWindowAdapter(new MapInfoWindowAdapter(this, markerSet));

回答2:

What is working for me is this:

Inside getInfoWindow(Marker marker):

Picasso.with(getActivity())
                            .load(URL)
                            .error(R.drawable.my_loader)
                            .placeholder(R.drawable.my_loader)
                            .into(userPhoto, new MarkerCallback(marker,URL,userPhoto));

Then create a class:

public class MarkerCallback implements Callback {
Marker marker=null;
String URL;
ImageView userPhoto;


MarkerCallback(Marker marker, String URL, ImageView userPhoto) {
    this.marker=marker;
    this.URL = URL;
    this.userPhoto = userPhoto;
}

@Override
public void onError() {
    //Log.e(getClass().getSimpleName(), "Error loading thumbnail!");
}

@Override
public void onSuccess() {
    if (marker != null && marker.isInfoWindowShown()) {
        marker.hideInfoWindow();

        Picasso.with(getActivity())
                .load(URL)                        
                .into(userPhoto);

        marker.showInfoWindow();
    }
}

}

来源：https://stackoverflow.com/questions/32725753/picasso-image-loading-issue-in-googlemap-infowindowadapter