android - 无法使用 Picasso 和 scrollGalleryView 从内存中删除位图

Question

我有一个 Activity ，我在其中加载位图 ScrollGalleryView使用毕加索。当我退出该 Activity 并再次进入时，内存未清空并抛出 OutOfMemory 错误。
我尝试在 Picasso 中使用 .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE) 但图像仍然加载并保存在内存中。我也尝试在按下后退按钮时回收位图，但我仍然没有运气。
这是我正在使用的代码:

//Method called in the onCreate that loads the photo in the scrollGalleryView:
private void loadPhotos() {
    savedImages = new ArrayList<Uri>();

    File file = new File(getPhotoDirectory());
    File[] files = file.listFiles();
    if (files != null) {
        for (File f : files) { // loop and print all file
            savedImages.add(Uri.fromFile(f));
        }
    }

    if (!savedImages.isEmpty()) {
        for (final Uri savedImage : savedImages) {
            if (savedImage.getLastPathSegment().contains(radiatorId)) {
                scrollGalleryView.setVisibility(View.VISIBLE);
                RadiatorSettingsMediaLoader mMediaLoader = new RadiatorSettingsMediaLoader(savedImage);
                scrollGalleryView.addMedia(MediaInfo.mediaLoader(mMediaLoader));
            }
        }
    }
}





class RadiatorSettingsMediaLoader implements MediaLoader {
    Uri savedImage;

    public RadiatorSettingsMediaLoader(Uri savedImage) {
        this.savedImage = savedImage;
    }

    @Override
    public boolean isImage() {
        return true;
    }

    @Override
    public void loadMedia(final Context context, final ImageView imageView,
                          final MediaLoader.SuccessCallback callback) {
        imageView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            public ViewTreeObserver.OnGlobalLayoutListener getLayoutListener() {
                return this;
            }

            @Override
            public void onGlobalLayout() {
                Picasso.with(getApplicationContext()).load(savedImage)
                        .resize(imageView.getWidth(), (imageView.getHeight()) - 175)
                        .centerInside()
                        .placeholder(imageView.getDrawable())
                        .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
                        .into(imageView, new Callback() {
                            @Override
                            public void onSuccess() {
                                callback.onSuccess();
                                imageView.setPadding(0, 0, 0, 175);
                                imageView.getViewTreeObserver().removeOnGlobalLayoutListener(getLayoutListener());
                                Picasso.with(getApplicationContext()).invalidate(new File(savedImage.getPath()));
                            }

                            @Override
                            public void onError() {
                                Toast.makeText(context, "non sono riuscito a caricare l'immagine", Toast.LENGTH_SHORT).show();
                                imageView.getViewTreeObserver().removeOnGlobalLayoutListener(getLayoutListener());
                                loadMedia(context, imageView, callback);

                            }
                        });
                imageViewsToClear.add(imageView);

            }
        });
    }

    @Override
    public void loadThumbnail(final Context context, final ImageView thumbnailView,
                              final MediaLoader.SuccessCallback callback) {


        thumbnailView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            public ViewTreeObserver.OnGlobalLayoutListener getLayoutListener() {
                return this;
            }

            @Override
            public void onGlobalLayout() {
                Picasso.with(context)
                        .load(savedImage)
                        .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE)
                        .into(thumbnailView, new Callback() {
                            @Override
                            public void onSuccess() {

                                callback.onSuccess();
                                thumbnailView.setLongClickable(true);
                                thumbnailView.setOnLongClickListener(new View.OnLongClickListener() {

                                    @Override
                                    public boolean onLongClick(View v) {
                                        AlertDialog.Builder builder = new AlertDialog.Builder(RadiatorSettingsActivity.this);

                                        builder.setTitle(R.string.safe_delete_photo_title).setMessage(R.string.safe_delete_photo_text);
                                        builder.setPositiveButton(R.string.delete, new DialogInterface.OnClickListener() {
                                            @Override
                                            public void onClick(DialogInterface dialog, int which) {
                                                File fdelete = new File(savedImage.getPath());
                                                if (fdelete.exists()) {
                                                    if (fdelete.delete()) {
                                                        deleteFileFromMediaStore(getContentResolver(), fdelete);
                                                        System.out.println("file Deleted ");
                                                        finish();
                                                        startActivity(getIntent().putExtra("PhotoRemoved", true));
                                                    } else {
                                                        System.out.println("file not Deleted :");
                                                    }
                                                }


                                            }
                                        });
                                        builder.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
                                            @Override
                                            public void onClick(DialogInterface dialog, int which) {
                                                dialog.dismiss();
                                            }
                                        });
                                        builder.show();
                                        return true;
                                    }
                                });
                                thumbnailView.getViewTreeObserver()
                                        .removeOnGlobalLayoutListener(getLayoutListener());
                            }


                            @Override
                            public void onError() {
                                Toast.makeText(context, "errore a caricare thumbnail", Toast.LENGTH_SHORT).show();
                                loadThumbnail(context, thumbnailView, callback);
                                thumbnailView.getViewTreeObserver()
                                        .removeOnGlobalLayoutListener(getLayoutListener());
                            }
                        });

                imageViewsToClear.add(thumbnailView);
            }
        });


    }

}

Answer 1

在你的程序中调用它

public void clearAllResources() {

                // Set related variables null

                System.gc();
                Runtime.getRuntime().gc();
            }

即 clearAllResources(); Activity 开始时