java - 如何删除查看寻呼机的特定位置

Question

我在我的 Android 应用程序中实现了 ViewPager。我想在其中添加一些图像，一切正常(图像添加)，但是当我想删除图像时，它正在工作并删除该图像，但它删除最后一张图像而不是我要删除的特定图像，我不知道如何获取特定图像的位置并将其删除。

public class PhotoAdd_Adapter extends PagerAdapter {
    private LayoutInflater inflater;
    private Context context;
    ArrayList<String> mylist;
    SharedPreferences sharedPreferences;
    JSONArray responsearray = null;
    private static final String TAG_PHOTO_ONE = "Gallery_Full";
    HashMap<String, String> get;
    LinearLayout addimages;
    String ImageID;
    ProgressBar progressBar;
    String finalimgpath, imageId;
    ImageView imageView, deletebtn;
    TextView no_image, p_id;
    private FragmentManager f_manager;
    int delPosition;

    public PhotoAdd_Adapter(Context context, ArrayList<String> mylist, FragmentManager f_manager) {
        this.f_manager = f_manager;
        this.context = context;
        this.mylist = mylist;
        inflater = LayoutInflater.from(context);
        sharedPreferences = context.getSharedPreferences(context.getString(R.string.prefs), 0);
    }
    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        container.removeView((View) object);
    }
    @Override
    public int getCount() {
        return mylist.size();
    }
    @Override
    public int getItemPosition(@NonNull Object object) {
        if(mylist.contains(object)){
            return mylist.indexOf(object);
        }else {
            return POSITION_NONE;
        }
//        return super.getItemPosition(object);
//        return PagerAdapter.POSITION_NONE;
    }
    @Override
    public Object instantiateItem(ViewGroup view, final int position) {
        View imageLayout = inflater.inflate(R.layout.photoadd_adapter, view, false);
        assert imageLayout != null;
        imageView = imageLayout.findViewById(R.id.image_adapter);
        deletebtn = imageLayout.findViewById(R.id.deletebtn);
        p_id = imageLayout.findViewById(R.id.p_id);
        this.delPosition = position;       
        String test = String.valueOf(mylist.get(position));
        String finalimgpaths = context.getString(R.string.moreimgpath) + test;
        Glide.with(context)
                .load(finalimgpaths)
                .into(imageView);
        view.addView(imageLayout, 0);
        deletebtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
//                showDialogBox();
                imageId = ImageID;
                Log.e("IMAGEIDONE", imageId);
                mylist.remove(position);
                notifyDataSetChanged();
                responsearray = responsearray(responsearray, position);
                new DeleteImage().execute(true);
            }
        });
        return imageLayout;
    }
    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view.equals(object);
    }
    @Override
    public void restoreState(Parcelable state, ClassLoader loader) {
    }
    @Override
    public Parcelable saveState() {
        return null;
    }
    class DeleteImage extends AsyncTask<Boolean, Void, String> {
        @Override
        protected String doInBackground(Boolean... booleans) {
            ProfileApi profileApi = new ProfileApi();
            String result = null;
            try {
                Log.e("IMAGEID", ImageID);
                result = profileApi.deleteImage(sharedPreferences.getString("id", ""), imageId);
                Log.e("DELETERESULT", result);
                JSONObject object = new JSONObject(result);
                if (object.getString("error").equalsIgnoreCase("false")) {

                    return "true";
                } else {
                    String errormsg = object.getString("response");
                    return errormsg;
                }
            } catch (ApiException e) {
                e.printStackTrace();
            } catch (JSONException e) {
                e.printStackTrace();
            }
            return null;
        }
        @Override
        protected void onPostExecute(String s) {
//            ad.hide();
            super.onPostExecute(s);
            try {
                if (s != null) {
                    Toast.makeText(context, "Image Deleted", Toast.LENGTH_SHORT).show();
                }
            } catch (IllegalStateException e) {
                e.printStackTrace();
            }
        }
    }
    public static JSONArray responsearray(JSONArray jarray, int pos) {
        JSONArray Njarray = new JSONArray();
        try {
            for (int i = 0; i < jarray.length(); i++) {
                if (i != pos)
                    Njarray.put(jarray.get(i));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return Njarray;
    }
}

Answer 1

您的问题是 View 寻呼机在删除图像任务完成之前重新加载。因此加载了同一组图像，但由于列表大小已修改，因此未加载最后一个图像。

解决方案:等待删除操作完成，然后再在 ViewPager 上调用 notificationDataSetChanged()