我们如何从 Sdcard 中获取基于 Android 时间戳具有唯一名称的图像

Question

我知道如何从 sdcard 中检索图像，但我找不到检索包含唯一时间戳及其名称的特定图像的解决方案。

当我存储到外部目录时，如何从具有唯一时间戳的 sdcard 获取图像？

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());

//folder stuff
File imagesFolder = new File(Environment.getExternalStorageDirectory(), "MyImages");
imagesFolder.mkdirs();

File image = new File(imagesFolder, "QR_" + timeStamp + ".png");
Uri uriSavedImage = Uri.fromFile(image);

如何从 sdcard 中检索上面的图像？

Answer 1

以下代码用于从文件名以 "QR_[eight int '-' Six int]" 开头的文件夹中检索文件

private void getFiles() {
    Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;

    File imagesFolder = new File(Environment.getExternalStorageDirectory(), "MyImages");

    String path = imagesFolder.getAbsolutePath();

    final String where = MediaStore.Images.Media.DATA + " like ? ";
    final String[] args = new String[]{path + File.separator + "QR_" + "%"};
    final String[] columns = {MediaStore.Images.Media.DATA};
    final Cursor cursor = getActivity().getContentResolver().query(uri, columns, where, args, null);
    final String pattern = Pattern.quote(path) + "/[^/]*";

    if (cursor != null && cursor.moveToFirst()) {

        do {
            final String curPath = cursor.getString(0);
            if (curPath.matches(pattern)) {
                final File file = new File(curPath);
                    if(file.getName().matches("\\d{8}-\\d{6}")) {
                        // your file
                    }
            }
        } while (cursor.moveToNext());
        cursor.close();
    }
}