读取系统所有图片和缩略图

超、凢脫俗 2022-08-18 10:54 99阅读 0赞

/**
           * 读取系统的 多媒体索引 获取 sd卡中的所有图片信息
           */
          public void initImagesIndex() {
                ImageCache. imgDirPathList = new ArrayList<String>();
                ImageCache. imagesIndex = new HashMap<String, List<Map<String, String>>>();
                ContentResolver cr = mContext.getContentResolver();
                String[] imagesProjection = { Images.ImageColumns. _ID, Images.ImageColumns.DATA , Images.ImageColumns.BUCKET_DISPLAY_NAME };
                 // 查询sd上所有的图片信息
                Cursor cur = cr.query(Images.Media. EXTERNAL_CONTENT_URI, imagesProjection, null , null, null);
                 if (cur.moveToFirst()) {
                       int _id; // 图片id
                      String data; // 图片Path 具体路径
                      String dirName; // 图片所在目录的名称
                       int _idColumn = cur.getColumnIndex(Images.ImageColumns._ID );
                       int data_idColcum = cur.getColumnIndex(Images.ImageColumns.DATA );
                       int dispalyname_Column = cur.getColumnIndex(Images.ImageColumns.BUCKET_DISPLAY_NAME );
                       do {
                            _id = cur.getInt(_idColumn);
                            data = cur.getString(data_idColcum);
                            dirName = cur.getString(dispalyname_Column);
                            HashMap<String, String> map = new HashMap<>();
                            map.put(CommonConst.ImageMap. ID, _id + "");
                            map.put(CommonConst.ImageMap. PATH, data);
                            map.put(CommonConst.ImageMap. DIR_NAME, dirName);
                             // 图片所在文件夹路径
                            String imgDirPath = data.substring(0, data.lastIndexOf("/" ));
                             if (!ImageCache.imagesIndex .containsKey(imgDirPath)) {
                                   // 当找不到 该图片所在文件夹路径 时 则创建一个新的List 并且注入到 Map 中
                                  List<Map<String, String>> list = new ArrayList<Map<String, String>>();
                                  list.add(map);
                                  ImageCache. imagesIndex.put(imgDirPath, list);
                                  Log. i(TAG, "img dir path = " + imgDirPath);
                            } else {
                                   // 找到的话 在原有的List 添加该图片信息
                                  ImageCache. imagesIndex.get(imgDirPath).add(map);
                            }
                             // 给图片所在文件夹路径 List 添加值 便于 计算出 adapter 使用
                             if (!ImageCache.imgDirPathList .contains(imgDirPath)) {
                                  ImageCache. imgDirPathList.add(imgDirPath);
                            }
                      } while (cur.moveToNext());
                }
                initImagesThumb();
          }
    
          /**
           * 初始化 读取 缩略图信息
           */
          public void initImagesThumb() {
                ContentResolver cr = mContext.getContentResolver();
                String[] imagesProjection = { Thumbnails. IMAGE_ID, Thumbnails.DATA };
                Cursor cur = cr.query(Thumbnails. EXTERNAL_CONTENT_URI, imagesProjection, null , null, null);
                 if (cur.moveToFirst()) {
                      String imagID; // 图片Path 具体路径
                      String imgThumbPath; // 图片所在目录的名称
                       int imagID_column = cur.getColumnIndex(Thumbnails.IMAGE_ID );
                       int imgThumbPath_column = cur.getColumnIndex(Thumbnails.DATA );
                       do {
                            imagID = cur.getString(imagID_column);
                            imgThumbPath = cur.getString(imgThumbPath_column);
                            ImageCache. imgThumbMap.put(imagID, imgThumbPath);
                      } while (cur.moveToNext());
                }
          }