我有一个onActivityResult从一个mediastore图像选择返回,我可以获得一个图像使用以下URI:

Uri selectedImage = data.getData();

将this转换为字符串会得到:

content://media/external/images/media/47

或路径给出:

/external/images/media/47

然而,我似乎找不到一种方法将其转换为绝对路径,因为我想将图像加载到位图中,而不必复制到某个地方。我知道这可以使用URI和内容解析器来完成,但这似乎在重新启动手机时中断,我猜MediaStore在重新启动之间没有保持其编号相同。


当前回答

从图库中获取图像后,只需要在下面的方法中传递URI,仅适用于Android 4.4 (KitKat):

public String getPath(Uri contentUri) {// Will return "image:x*"

    String wholeID = DocumentsContract.getDocumentId(contentUri);

    // Split at colon, use second item in the array
    String id = wholeID.split(":")[1];

    String[] column = { MediaStore.Images.Media.DATA };

    // Where id is equal to
    String sel = MediaStore.Images.Media._ID + "=?";

    Cursor cursor = getContentResolver().query(
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI, column, sel,
            new String[] { id }, null);

    String filePath = "";

    int columnIndex = cursor.getColumnIndex(column[0]);

    if (cursor.moveToFirst()) {
        filePath = cursor.getString(columnIndex);
    }

    cursor.close();
    return filePath;
}

其他回答

作为一个附加组件,如果在尝试打开输入流之前需要查看文件是否存在,可以使用DocumentsContract。

(Kotlin代码)

var iStream = null
if(DocumentsContract.isDocumentUri(context,myUri)) {
   val pfd: ParcelFileDescriptor? = context.contentResolver.openFileDescriptor(
            myUri, "r") ?: return null
   iStream = ParcelFileDescriptor.AutoCloseInputStream(pfd)
}

像下面这样获取Uri。

//* get cursor like normal

Then

while (cursor.moveToNext()) {
    Uri uri = ContentUris.withAppendedId(
    MediaStore.Images.Media.EXTERNAL_CONTENT_URI, id);
}

下面API 19使用这段代码从URI中获取文件路径:

public String getRealPathFromURI(Context context, Uri contentUri) {
  Cursor cursor = null;
  try { 
    String[] proj = { MediaStore.Images.Media.DATA };
    cursor = context.getContentResolver().query(contentUri,  proj, null, null, null);
    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
    cursor.moveToFirst();
    return cursor.getString(column_index);
  } finally {
    if (cursor != null) {
      cursor.close();
    }
  }
}

我是这样做的:

    Uri queryUri = MediaStore.Files.getContentUri("external");
    String columnData = MediaStore.Files.FileColumns.DATA;
    String columnSize = MediaStore.Files.FileColumns.SIZE;

    String[] projectionData = {MediaStore.Files.FileColumns.DATA};


    String name = null;
    String size = null;

    Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
    if ((cursor != null)&&(cursor.getCount()>0)) {
        int nameIndex = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
        int sizeIndex = cursor.getColumnIndex(OpenableColumns.SIZE);

        cursor.moveToFirst();

        name = cursor.getString(nameIndex);
        size = cursor.getString(sizeIndex);

        cursor.close();
    }

    if ((name!=null)&&(size!=null)){
        String selectionNS = columnData + " LIKE '%" + name + "' AND " +columnSize + "='" + size +"'";

        Cursor cursorLike = getContentResolver().query(queryUri, projectionData, selectionNS, null, null);

        if ((cursorLike != null)&&(cursorLike.getCount()>0)) {
            cursorLike.moveToFirst();
            int indexData = cursorLike.getColumnIndex(columnData);
            if (cursorLike.getString(indexData) != null) {
                result = cursorLike.getString(indexData);
            }
            cursorLike.close();
        }
    }

    return result;

这里您可以得到文件的名称

String[] projection = {MediaStore.MediaColumns.DISPLAY_NAME};
                    Uri uri = data.getData();
                    String fileName = null;
                    ContentResolver cr = getActivity().getApplicationContext().getContentResolver();

                    Cursor metaCursor = cr.query(uri,
                            projection, null, null, null);
                    if (metaCursor != null) {
                        try {
                            if (metaCursor.moveToFirst()) {
                                fileName = metaCursor.getString(0);
                            }
                        } finally {
                            metaCursor.close();
                        }
                    }