I have a little bit strange question: this time everything works, but I can't understand why.
AFAIK it's possible to mount more than one sd card. Everything will be mounted to /mnt directory. (is it true?)
On my device there is only one sd card which mounted to /mnt/sdcard. And in my application I open files from it. I'm using next code:
private void open() {
// get file extension
String extension = "";
int dotIndex = downloadedFile.lastIndexOf('.');
if (dotIndex != -1) {
extension = downloadedFile.substring(dotIndex + 1, downloadedFile.length());
}
// create an intent
Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
Uri data = Uri.fromFile(new File(downloadedFile));
String type = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
if (type == null || type.length() == 0) {
// if there is no acceptable mime type
type = "application/octet-stream";
}
intent.setDataAndType(data, type);
// get the list of the activities which can open the file
List resolvers = context.getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
if (resolvers.isEmpty()) {
(new AlertDialog.Builder(context)
.setMessage(R.string.AttachmentUnknownFileType)
.setNeutralButton(R.string.NeutralButtonText, null)
.create()).show();
} else {
context.startActivity(intent);
}
}
Actually downloadedFile variable has value like file:///sdcard/mydir/myfile.txt. But the code works. Why? How Android understand what /sdcard/... is the same as /mnt/sdcard/...?
And main question: what happened if sd card will be mounted to other dir (for exmaple, /mnt/another-sd/ or even /media/sd)? What if more than one sd cards will be mounted: how android understand what card to use?
Thank you for any help! Have a good day!
It's simple android configueres the mounting over a settings file on phone boot so if there are mor sdcards Android will simply prefer one of them to set as
/sdcard/
so when the mount settings change your code is simply useless you can only hope the settings being untouched .
Every company that procuces Android smartphones use the "sdcard" path even custom roms like use it
Related
I have an Android app that needs to let the user select some pictures from the gallery and send these pictures to the backend (together with some other data).
To allow the user to select the pictures I have the following in my Fragment:
private void pickImages() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
startActivityForResult(intent, PICK_PHOTO_FOR_AVATAR);
}
I get the result of the selected photos by the user in here:
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PICK_PHOTO_FOR_AVATAR && resultCode == Activity.RESULT_OK) {
if (data == null) {
//Display an error
Toast.makeText(getActivity(), "There was an error getting the pictures", Toast.LENGTH_LONG).show();
return;
}
ClipData clipData = data.getClipData();
String fileName = null, extension = null;
//if ClipData is null, then we have a regular file
if (clipData == null) {
//get the selected file uri
fileName = FileUtils.getPath(getActivity(), data.getData());
//obtain the extension of the file
int index = fileName.lastIndexOf('.');
if (index > 0) {
extension = fileName.substring(index + 1);
if (extension.equals("jpg") || extension.equals("png") || extension.equals("bmp") || extension.equals("jpeg"))
isAttachedFile = true;
}
}
ArrayList<Uri> photosUris = new ArrayList<>();
//for each image in the list of images, add it to the filesUris
if (clipData != null) for (int i = 0; i < clipData.getItemCount(); i++) {
ClipData.Item item = clipData.getItemAt(i);
Uri uri = item.getUri();
switch (i) {
case 0:
picture1Uri = uri;
break;
case 1:
picture2Uri = uri;
break;
}
photosUris.add(uri);
}
else if (isAttachedFile) {
Uri uri = Uri.parse(fileName);
picture1Uri = uri;
photosUris.add(uri);
}
uris = photosUris;
if (picture1Uri != null) {
image1.setVisibility(View.VISIBLE);
image1.setImageURI(picture1Uri);
}
if (picture2Uri != null) {
image2.setVisibility(View.VISIBLE);
image2.setImageURI(picture2Uri);
}
}
I then send the list of URIs to the Presenter, where I execute my MultiPart Retrofit call to the backend:
//obtain the file(s) information of the message, if any
if (uris != null && uris.size() > 0) {
for (int i = 0; i < uris.size(); i++) {
File file = null;
//this is the corect way to encode the pictures
String encodedPath = uris.get(i).getEncodedPath();
file = new File(encodedPath);
builder.addFormDataPart("photos[]", file.getName(), RequestBody.create(MediaType.parse("multipart/form-data"), file));
}
}
MultipartBody requestBody = builder.build();
//send the newly generated ticket
Call<GenerateNewTicketResponse> generateNewTicketCall = OperatorApplication.getApiClient().generateNewTicket(Constants.BEARER + accessToken, requestBody);
The problem is that this sometimes works, sometimes doesn't. Sometimes I get the error "java.io.FileNotFoundException", which throws me in the onFailure() callback of the Retrofit call.
I found the following stackoverflow post Reading File from Uri gives java.io.FileNotFoundException: open failed: ENOENT but I'm not exactly sure how to implement the general suggestion in that response to my particular situation.
What would be the right way to get the right path towards the pictures selected by the user such that I can create files out of them and attach them in my MultiPart request?
Commonsware suggested to
Use a ContentResolver and openInputStream() to get an InputStream on the content pointed to by the Uri. Then, pass that to your decoding logic, such as BitmapFactory and its decodeStream() method.
, but I'm not sure exactly how to do that programmatically.
Any help would be appreciated.
To allow the user to select the pictures I have the following in my Fragment:
This code is using ACTION_GET_CONTENT. Particularly on Android 7.0+, generally that (and ACTION_OPEN_DOCUMENT) will return Uri values with a content scheme. Your code assumes that you are getting Uri values with a file scheme, where the path actually has meaning. Moreover, your code assumes that the user is picking files on the filesystem that you can access, and there is nothing that forces the user to do that. ACTION_GET_CONTENT can be supported by apps where their content is:
A local file on external storage
A local file on internal storage for the other app
A local file on removable storage
A local file that is encrypted and needs to be decrypted on the fly
A stream of bytes held in a BLOB column in a database
A piece of content on the Internet that needs to be downloaded by the other app first
Content that is generated on the fly
...and so on
Instead of using RequestBody.create(), use the InputStreamRequestBody from this OkHttp issue comment. You provide the same media type as before, but instead of a File (that you are incorrectly creating), you provide a ContentResolver (from getContentResolver() on a Context) and the Uri.
This blog post demonstrates how to use InputStreamRequestBody (specifically a Kotlin port of the original) to upload content in this fashion. This blog post provides another look at the same problem and a similar solution.
So I've created this simple app that asks the user questions (it's like a truth or dare game).
The questions are saved in a .json-file in SD-Card > Android > data > [package name] > files.
I want to make it possible, however, to add or delete those questions by manually editing or exchanging that .json-file in which the questions are saved (so that those new questions then appear in the app).
I already understand that the app needs to call the getExternalFilesDir() method somewhere, so that a directory that I can find in the device's file manager is created in the first place. However - as you probably have guessed - when I open that directory, the "files" folder is empty. (I know the .json-files must be in there since the app is working fine!)
Now my question:
Is there any way I can view and edit those .json-files? I don't care if the solution includes using a PC or some program.
Or should I maybe not save the questions in a .json-file but in a .txt-file instead? Or should I use a different directory to save my question files to begin with??
I would appreciate a detailed answer, since I'm obviously new.
Thanks in advance!
P.S.: I can include code on request.
EDIT: I don't want to edit those files from code, I already know how to do that. My question in particular is about whether there is a possibility to edit the json files using a text editor for example or exchanging the files using copy paste.
Code:
public void copy() {
Context Context = getApplicationContext();
String DestinationFile = Context.getExternalFilesDir(null).getPath() + File.separator + "fragenAdvanced.json";
if (!new File(DestinationFile).exists()) {
try {
CopyFromAssetsToStorage(Context, "fragenAdvanced.json", DestinationFile);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
private void CopyFromAssetsToStorage(Context Context, String SourceFile, String DestinationFile) throws IOException {
InputStream IS = Context.getAssets().open(SourceFile);
OutputStream OS = new FileOutputStream(DestinationFile);
CopyStream(IS, OS);
OS.flush();
OS.close();
IS.close();
}
private void CopyStream(InputStream Input, OutputStream Output) throws IOException { //brauche ich das?
byte[] buffer = new byte[5120];
int length = Input.read(buffer);
while (length > 0) {
Output.write(buffer, 0, length);
length = Input.read(buffer);
}
}
This is how I save the file to storage.
there is 3 way to save your user data but your way is not secure because the user has access on it.
the first way is saving user data in SharedPreferences , it's very simple to use , but if user clears the app catch, the data will be deleted ( you can just convert your json to string and save it in sharedPreferences , for converting string to json you can use Gson library )
second way is using SQlite and save data on local database , it will be deleted by clear stroge and still not good for important data
the final way is using remote database and get data from api
I am working on a sample project in unity android where application reads a textfile in an OTG pen drive connected to the android phone, the problem is my code works fine in some devices but it doesn't work in some devices. I am unable to figure out the main cause even through the logcat extreme as it doesn't throw any error at all that specifies code error.
I tried adding text logs to print text in between the code to see which texts are not printed, which would further tell me that after which line code stopped working but all the texts are printed.
This is my code that detects the USB and returns true if a text file is present in USB:
public void LocateFile()
{
textfileData = null;
using (AndroidJavaClass unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer"))
{
using (AndroidJavaObject context = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity"))
{
// Get all available external file directories (emulated and USBdrives)
AndroidJavaObject[] externalFilesDirectories = context.Call<AndroidJavaObject[]>("getExternalFilesDirs", (object)null);
AndroidJavaObject emulated = null;
AndroidJavaObject USBdrive = null;
for (int i = 0; i < externalFilesDirectories.Length; i++)
{
AndroidJavaObject directory = externalFilesDirectories[i];
using (AndroidJavaClass environment = new AndroidJavaClass("android.os.Environment"))
{
bool isRemovable = environment.CallStatic<bool>("isExternalStorageRemovable", directory);
bool isEmulated = environment.CallStatic<bool>("isExternalStorageEmulated", directory);
if (isEmulated)
{
emulated = directory;
}
else if (isRemovable && isEmulated == false)
{
USBdrive = directory;
}
}
}
// Return the USBdrive if available
if (USBdrive != null)
{
if (File.Exists(USBdrive.Call<string>("getAbsolutePath") + "/serial.txt"))
{
textfileData = File.ReadAllText(USBdrive.Call<string>("getAbsolutePath") + "/serial.txt");
}
}
}
}}
This code works on my android phone and returns true after detecting the file present in pendrive.
Can anyone tell me what could be the issue and point me in the right direction, I will greatly appreciate your support on this.
This locateFile() function is called on Update().
Update: I tried to debug the number of storage found in mobile and code is not reading the USB. It reads internal and SD storage perfectly.
Nokia 5 is the only phone the code has worked on so far but in 99% android devices GetExternalFilesDir is not reading usb storage.
Please someone tell me an alternate or how do I get this to work, it is very important.
This question is related to this previously answered question Share Image on Android Application from Unity Game
My question is this:
Is there a way to share the image WITHOUT using a file? I'd like to remove the sd card read/write permission on Android. I'm not a Java programmer, so I'm having a heck of a time getting it working. None of my attempts have yielded anything.
"Programmer" answered the previous question with the below code, which works great for me. I basically want to use the variable imageBytes instead of the file. Is this even possible?
void takeScreenShotAndShare()
{
StartCoroutine(takeScreenshotAndSave());
}
private IEnumerator takeScreenshotAndSave()
{
string path = "";
yield return new WaitForEndOfFrame();
Texture2D screenImage = new Texture2D(Screen.width, Screen.height);
//Get Image from screen
screenImage.ReadPixels(new Rect(0, 0, Screen.width, Screen.height), 0, 0);
screenImage.Apply();
//Convert to png
byte[] imageBytes = screenImage.EncodeToPNG();
System.IO.Directory.CreateDirectory(Application.persistentDataPath + "/GameOverScreenShot");
path = Application.persistentDataPath + "/GameOverScreenShot" + "/DiedScreenShot.png";
System.IO.File.WriteAllBytes(path, imageBytes);
StartCoroutine(shareScreenshot(path));
}
private IEnumerator shareScreenshot(string destination)
{
string ShareSubject = "Picture Share";
string shareLink = "Test Link" + "\nhttps://stackoverflow.com/questions/36512784/share-image-on-android-application-from-unity-game";
string textToShare = "Text To share";
Debug.Log(destination);
if (!Application.isEditor)
{
AndroidJavaClass intentClass = new AndroidJavaClass("android.content.Intent");
AndroidJavaObject intentObject = new AndroidJavaObject("android.content.Intent");
intentObject.Call<AndroidJavaObject>("setAction", intentClass.GetStatic<string>("ACTION_SEND"));
AndroidJavaClass uriClass = new AndroidJavaClass("android.net.Uri");
AndroidJavaObject uriObject = uriClass.CallStatic<AndroidJavaObject>("parse", "file://" + destination);
intentObject.Call<AndroidJavaObject>("putExtra", intentClass.GetStatic<string>("EXTRA_STREAM"), uriObject);
intentObject.Call<AndroidJavaObject>("putExtra", intentClass.GetStatic<string>("EXTRA_TEXT"), textToShare + shareLink);
intentObject.Call<AndroidJavaObject>("putExtra", intentClass.GetStatic<string>("EXTRA_SUBJECT"), ShareSubject);
intentObject.Call<AndroidJavaObject>("setType", "image/png");
AndroidJavaClass unity = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
AndroidJavaObject currentActivity = unity.GetStatic<AndroidJavaObject>("currentActivity");
currentActivity.Call("startActivity", intentObject);
}
yield return null;
}
Unity3d share image on android
You can directly pass the byte array, no need to convert it to file -> uri -> string
Below are java code, but you can easily translate this to JNI wrapper calls
Bundle bundle = new Bundle();
bundle.putByteArray("byteArr", imageBytes); //put byte array to bundle!!!
Intent intent = new Intent(...);
intent.putExtra(bundle );
To retrieve the image byte array in another activity, use below code:
getIntent().getByteArrayExtra("byteArr");
If you wrap each above function calls into a corresponding JNI function, it would be very tedious. You can on the other hand:
Create an android library project
Add two static java functions, one is saveByteArrayToBundle(...), and the other is getByteArrayFromBundle(...)
Compile the android library into an aar file;
then put the aar file into the Assets/ folder (actually any subfolders will do)
Then call the two static java functions as you have done in the OP
Refer to below tutorials if you need to go through step-by-step:
Step-by-Step guide for developing Android Plugin for Unity3D (I)
Step-by-Step guide for developing Android Plugin for Unity3D (II)
I want to create a Music player which can download a song online and add it to MediaStore. I'm using Download Manager and allow MediaScanner scan this file when download completed.
DownloadManager.Request request ....
request.allowScanningByMediaScanner();
...
downloadManager.enqueue(request);
It's work fine in android 5.0 and above.
But the song was downloaded using codec (opus) which not supported in android below lollipop version, so MediaScanner doesn't add this file to MediaStore.
That's my problem, my app can play opus codec but the song didn't exist in MediaStore after it has downloaded, so my app can't find this song.
How to force MediaScanner add downloaded file to MediaStore.Audio as a Music track. If can not, how can I manual add this song to MediaStore.Audio after download completed:
public class BroadcastDownloadComplete extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals("android.intent.action.DOWNLOAD_COMPLETE")) {
//addSongToMediaStore(intent);
}
}
}
From the source code here, we can see the final implementation of the scanner has two steps to scan an audio file. If either of these two step fail, the audio file will not insert into media provider.
step 1 check the file extension
static bool FileHasAcceptableExtension(const char *extension) {
static const char *kValidExtensions[] = {
".mp3", ".mp4", ".m4a", ".3gp", ".3gpp", ".3g2", ".3gpp2",
".mpeg", ".ogg", ".mid", ".smf", ".imy", ".wma", ".aac",
".wav", ".amr", ".midi", ".xmf", ".rtttl", ".rtx", ".ota",
".mkv", ".mka", ".webm", ".ts", ".fl", ".flac", ".mxmf",
".avi", ".mpeg", ".mpg"
};
static const size_t kNumValidExtensions =
sizeof(kValidExtensions) / sizeof(kValidExtensions[0]);
for (size_t i = 0; i < kNumValidExtensions; ++i) {
if (!strcasecmp(extension, kValidExtensions[i])) {
return true;
}
}
return false;
}
More extensions have been added since Android 5.0. The common container for opus codec is ogg, this extension exists before Android 5.0. Assume your audio file extension is ogg, the scanning process is fine at this step.
step2 retrieve metadata
After the first step passed, the scanner need to retrieve media's metadata for later database insertion. I think the scanner do the codec level checking at this step.
sp<MediaMetadataRetriever> mRetriever(new MediaMetadataRetriever);
int fd = open(path, O_RDONLY | O_LARGEFILE);
status_t status;
if (fd < 0) {
// couldn't open it locally, maybe the media server can?
status = mRetriever->setDataSource(path);
} else {
status = mRetriever->setDataSource(fd, 0, 0x7ffffffffffffffL);
close(fd);
}
if (status) {
return MEDIA_SCAN_RESULT_ERROR;
}
For Android version before 5.0, the scanner might be failed at this step. Because of lacking of built-in opus codec support, setDataSource will get failed at last. The media file won't be added to media provider finally.
suggested solution
Because we know the audio file will be added to
MediaStore.Audio.Media.EXTERNAL_CONTENT_URI
we can do database operation manually. If you want your audio file keeps consistent with other audio files in the database, you have to retrieve all the metadata by yourself. Since you can play the opus file, I think it's easy to retrieve the metadata.
// retrieve more metadata, duration etc.
ContentValues contentValues = new ContentValues();
contentValues.put(MediaStore.Audio.AudioColumns.DATA, "/mnt/sdcard/Music/example.opus");
contentValues.put(MediaStore.Audio.AudioColumns.TITLE, "Example track");
contentValues.put(MediaStore.Audio.AudioColumns.DISPLAY_NAME, "example");
// more columns should be filled from here
Uri uri = getContentResolver().insert(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, contentValues);
Log.d(TAG, uri.toString());
After that, you app can find the audio file.
getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI...
You can use MediaScannerConnection to ask Android to scan a file to be included as media. You'll want to use the scanFile() static method.