毕加索没有在第一次应用程序启动时加载图像

Question

我有Activity 和GoogleMap，我向服务器发送请求，解析JSON 响应并添加Markers，使用毕加索加载图标。

问题

接下来的问题是：当我关闭应用程序并再次打开它时，数据也会加载（网址也加载得很好），Markers 会添加到GoogleMap，但它们有默认图标，Picasso 不会加载新图标图标（未调用 onBitmapLoaded()）。当我完成Activity 并重新启动它（没有关闭应用程序）时，新标记的图标也会加载。

我对毕加索目标的实现：

public class PicassoMarker implements Target {
    private static final String TAG = "PicassoMarker";
    private Marker marker;
    private LoadingCallBacks loadingCallBacks;

    public PicassoMarker(Marker marker) {
        this.marker = marker;
    }

    public PicassoMarker(Marker marker, LoadingCallBacks loadingCallBacks) {
        this.marker = marker;
        this.loadingCallBacks = loadingCallBacks;
    }

    @Override
    public int hashCode() {
        return marker.hashCode();
    }

    @Override
    public boolean equals(Object o) {
        if (o instanceof PicassoMarker) {
            Marker marker = ((PicassoMarker) o).marker;
            return this.marker.equals(marker);
        } else {
            return false;
        }
    }

    @Override
    public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
        marker.setIcon(BitmapDescriptorFactory.fromBitmap(bitmap));
        Log.d(TAG, "onBitmapLoaded() -> " +
                "\nBitmap:" +
                "\n\twidth: " + bitmap.getWidth() +
                "\n\theight: " + bitmap.getHeight() /*+
                "\nCanvas:" +
                "\n\twidth: " + resultBitmap.getWidth() +
                "\n\theight: " + resultBitmap.getHeight()*/
        );

        if (loadingCallBacks != null) {
            loadingCallBacks.onLoaded(bitmap);
        }
    }

    @Override
    public void onBitmapFailed(Drawable errorDrawable) {
        Log.e(TAG, "onBitmapFailed()");
    }

    @Override
    public void onPrepareLoad(Drawable placeHolderDrawable) {
        Log.d(TAG, "onPrepareLoad()");
    }

    public void setLoadingCallBacks(LoadingCallBacks loadingCallBacks) {
        this.loadingCallBacks = loadingCallBacks;
    }

    public interface LoadingCallBacks {
        void onLoaded(Bitmap bitmap);
    }
}

还有我的AsyncTask 用于发送请求并添加Markers：

new AsyncTask<String, Void, ArrayList<MarkerDataModel>>() {
            private ArrayList<MarkerDataModel> markerDataModels = new ArrayList<>();

            @Override
            protected void onPreExecute() {
            }

            @Override
            protected ArrayList<MarkerDataModel> doInBackground(String... params) {
                // Parsing JSON ...

                return markerDataModels;
            }

            @Override
            protected void onPostExecute(ArrayList<MarkerDataModel> markerDataModels) {
                if (markerDataModels != null && markerDataModels.size() != 0) {
                    MarkerDataModel markerDataModel;

                    for (int i = 0; i < markerDataModels.size(); i++) {
                        markerDataModel = markerDataModels.get(i);

                        Marker marker = googleMap.addMarker(new MarkerOptions()
                                .position(new LatLng(markerDataModel.getLat(), markerDataModel.getLng()))
                                .title(markerDataModel.getLabel()));

                        PicassoMarker picassoMarker picassoMarker = new PicassoMarker(marker);
                        Picasso.
                                with(activityContext)
                                .load(markerDataModel.getIcon())
                                //.memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
                                //.networkPolicy(NetworkPolicy.NO_CACHE)
                                .into(picassoMarker);
                    }
                }
            }
        }.execute("http://example.com");

Answer 1

解决方案

我已经使用Glide 解决了问题。

这是从网络加载Markers'数据并使用Glide设置新图标的示例代码：

new AsyncTask<String, Void, ArrayList<MarkerDataModel>>() {

            @Override
            protected void onPreExecute() {
                ...
            }

            @Override
            protected ArrayList<MarkerDataModel> doInBackground(String... params) {
                ArrayList<MarkerDataModel> markerDataModels = new ArrayList<>();

                Send request and parse response...

                return markerDataModels;
            }

            @Override
            protected void onPostExecute(ArrayList<MarkerDataModel> markerDataModels) {
                if (markerDataModels != null && markerDataModels.size() != 0) {

                    for (int i = 0; i < markerDataModels.size(); i++) {
                        MarkerDataModel markerDataModel = markerDataModels.get(i);

                        final Marker marker = googleMap.addMarker(new MarkerOptions()
                                .position(new LatLng(markerDataModel.getLat(), markerDataModel.getLng()))
                                .title(markerDataModel.getLabel()));

            // Getting icon's URL from DataModel and loading icon
            Glide
                .with(activityContext)
                .load(markerDataModel.getIcon())
                .asBitmap()
                .into(new SimpleTarget<Bitmap>() {
                @Override
                public void onResourceReady(Bitmap resource, GlideAnimation<? super Bitmap> glideAnimation) {
                    // Setting new icon for Marker
                    marker.setIcon(BitmapDescriptorFactory.fromBitmap(resource));
                }
                });
                    }
                }
            }
        }.execute(...);

而MarkerDataModel 是用于存储Marker's 数据的简单类：

public class MarkerDataModel {

    public MarkerDataModel() {
    }

    private final String TAG = "MarkerDataModel";

    public static final int TYPE_PRIMARY = 1;
    public static final int TYPE_PEOPLE = 2;

    private int type;
    private int id;
    private double lat;
    private double lng;
    private Marker marker;

    /**
     * TYPE_PRIMARY
     **/
    private String icon;
    private String label;
    private String nameShort;
    private String nameFull;
    private String phone;
    private String information;
    private String website;
    private String sliderImages;

    /**
     * TYPE_PEOPLE
     **/
    private String photoUrl;
    private String uniqueId;
    private String registerTime;

    public MarkerDataModel(int type,
                           int id,
                           double lat,
                           double lng,
                           String icon,
                           String label,
                           String nameShort,
                           String nameFull,
                           String phone,
                           String information,
                           String website,
                           String sliderImages) {

        this.type = type;
        this.id = id;
        this.lat = lat;
        this.lng = lng;
        this.icon = icon;
        this.label = label;
        this.nameShort = nameShort;
        this.nameFull = nameFull;
        this.phone = phone;
        this.information = information;
        this.website = website;
        this.sliderImages = sliderImages;
    }

    public MarkerDataModel(int type,
                           int id,
                           double lat,
                           double lng,
                           String photoUrl,
                           String uniqueId,
                           String registerTime) {
        this.type = type;
        this.lat = lat;
        this.lng = lng;
        this.photoUrl = photoUrl;
        this.uniqueId = uniqueId;
        this.registerTime = registerTime;
    }

    /**
     * Getters
     */

    public int getType() {
        return type;
    }

    @Nullable
    public Marker getMarker() {
        return marker;
    }

    public int getId() {
        return id;
    }

    public double getLat() {
        return lat;
    }

    public double getLng() {
        return lng;
    }

    /**
     * TYPE_PRIMARY
     **/

    public String getIcon() {
        return icon;
    }

    public String getInformation() {
        return information;
    }

    public String getLabel() {
        return label;
    }

    public String getNameFull() {
        return nameFull;
    }

    public String getNameShort() {
        return nameShort;
    }

    public String getPhone() {
        return phone;
    }

    public String getSliderImages() {
        return sliderImages;
    }

    public String getWebsite() {
        return website;
    }


    /**
     * TYPE_PEOPLE
     **/
    public String getPhotoUrl() {
        return photoUrl;
    }

    public String getUniqueId() {
        return uniqueId;
    }

    public String getRegisterTime() {
        return registerTime;
    }


    @Nullable
    public LatLng getLatLng() {
        try {
            return new LatLng(lat, lng);
        } catch (Exception ex) {
            Log.e(TAG, "getLatLng() -> ", ex);
            return null;
        }
    }

    /**
     * Setters
     */

    public void setMarker(Marker marker) {
        this.marker = marker;
    }
}

好处

在TYPE_PRIMARY 和TYPE_PEOPLE 之间切换，您可以像这样捕获点击的Marker 类型：

googleMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
    @Override
    public boolean onMarkerClick(Marker marker) {
        MarkerDataModel markerDataModel = markerAllHashMap.get(marker);
        int type;

        try {
            Log.d(TAG, "onMarkerClick() -> " + markerDataModel.getType());
        } catch (Exception ex) {
            Log.e(TAG, "onMarkerClick() -> ", ex);
        }

        try {
            type = markerDataModel.getType();
        } catch (Exception ex) {
            type = -1;
        }

        switch (type) {
            case MarkerDataModel.TYPE_PRIMARY: {
                // Do something for TYPE_PRIMARY Marker
                break;
            }
            case MarkerDataModel.TYPE_PEOPLE: {
                // Do something for TYPE_PEOPLE Marker (e.g. show user's info)
                break;
            }
            default: {
                // Type == -1
                marker.showInfoWindow();
                break;
            }
        }

        // Animate to center
        googleMap.animateCamera(CameraUpdateFactory.newCameraPosition(new CameraPosition.Builder()
                .target(marker.getPosition())
                .zoom(18)
                .build()));

        return true;
    }
});