问题描述
我在 onActivityResult
中获取文件选择器的结果并构建 DocumentUriUsingTree
。
现在我用这个 DocumentUri
,构建一个 DocumentFile
来创建一个新文件夹。
onActivityResult:
if (resultCode == RESULT_OK) {
uri = data.getData();
int takeFlags = data.getFlags();
takeFlags &= (Intent.FLAG_GRANT_READ_URI_PERMISSION |
Intent.FLAG_GRANT_WRITE_URI_PERMISSION );
if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.O_MR1) {
getContext().getContentResolver().takePersistableUriPermission(uri,Intent.FLAG_GRANT_READ_URI_PERMISSION |
Intent.FLAG_GRANT_WRITE_URI_PERMISSION
);
}
DocumentFile subfolderDf = DocumentFile.fromTreeUri(this,uri);
subfolderDf.createDirectory("TestFolder");
uriDirFolder = uri.toString();
editor = getSharedPreferences(PREFS_NAME,MODE_PRIVATE).edit();
editor.putString(PREF_FILE_OBSERVER,uriDirFolder);
editor.apply();
}
resultUri == uriDirFolder 从 SharedPreference
get-Methode 获取
Uri docUriTree = DocumentsContract.buildDocumentUriUsingTree(Uri.parse(resultUri),DocumentsContract.getTreeDocumentId(Uri.parse(resultUri)));
docTreeUri = content://com.android.externalstorage.documents/tree/3339-6133%3AStorage%20Card%2FMusic%....
DocumentFile df = DocumentFile.fromTreeUri(this,docUriTree);
DocumentFile dirDf = df.createDirectory(dirName);
dirDf 看起来像 content://com.android.externalstorage.documents/tree/3339-6133%3AStorage%....dirName
df = DocumentFile.fromTreeUri(this,dirDf.getUri());
df 返回父文件夹而不是新创建的文件夹
我需要新文件夹中的 DocumentFileUri
才能使用 OutputStream
将文件保存到其中。
我在这里做错了什么?
谢谢, 亚历杭德罗
解决方法
DocumentFile subfolderDf = DocumentFile.fromTreeUri(this,uri); subfolderDf.createDirectory("TestFolder");
更改为:
DocumentFile folder = DocumentFile.fromTreeUri(this,uri);
DocumentFile subfolder = folder.createDirectory("TestFolder");
if ( subfolder == null )
{
Toast.makeText(context,"Sorry,could not create a subfolder with name TestFolder",Toast.LENGTH_LONG).show();
return;
}
Toast.makeText(context,"Created a subfolder with name TestFolder: " + subfolder.getUri().toString(),Toast.LENGTH_LONG).show();