I've been using the way the system saves screenshots to save my bitmaps to the disk and gallery. This works in Android 4.2 and before but not in Android 4.3.
Relevant code :
Uri imageUri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
OutputStream out = resolver.openOutputStream(uri);
Full code here.
In 4.3 (new Nexus 7) however, I get a FileNotFoundException on the second line. I couldn't see any changes in 4.3 relevant to this on the website.
So what is the right way to save an image to the disk and gallery?
Verified :
storage is mounted with this method
imageUri is not null (usually something like "content://media/external/images/media/2034")
manifest has permission android.permission.WRITE_EXTERNAL_STORAGE
This is the way I save bitmaps to the Gallery:
Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
Uri contentUri; //instantiate Uri with location of image
mediaScanIntent.setData(contentUri);
context.sendBroadcast(mediaScanIntent);
In your manifest file try with change target sdk to 18.-
<uses-sdk android:minSdkVersion="7"
android:targetSdkVersion="18"/>
It might solve your prob(May not). In 4.3 JELLY_BEAN_MR2, android did couple of changes and android clearly written that Your app might misbehave in a restricted profile environment. so please look at http://developer.android.com/about/versions/android-4.3.html
I have these permission in my Manifest.
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
But I am using a Target SDK version 15. Is there a requirement that you have to use a target SDK 18?
BTW:
Here is a sample code for downloading profile pictures from Facebook:
private class DownloadProfilePicTask extends AsyncTask<Void,String,String> {
Bitmap profilePic;
String fileName;
String id;
String type;
URL img_value;
public DownloadProfilePicTask(String i,String ty)
{
id = i;
if(id==null)
{
//Log.v("Id is null", "Error");
}
//Log.v("Download Profile Pic Task initialized for id:",id);
type = ty;
}
#Override
protected String doInBackground(Void...param) {
String root = Environment.getExternalStorageDirectory().toString();
if(root==null)
{
return null;
}
try{
profilePic = BitmapFactory.decodeStream(img_value.openConnection().getInputStream());
}
catch (IOException e) {
e.printStackTrace();
}
if(profilePic == null)
{
//Log.v("profilePic is null", "Error");
}
//Log.v("Root for saving images",root );
File myDir = new File(root + "/saved_images");
myDir.mkdirs();
fileName = root + "/saved_images/" + id + ".png";
//Log.v("filename is ",fileName);
File file = new File (fileName);
fileName = file.getPath();
if (file.exists ()) file.delete ();
try {
FileOutputStream out = new FileOutputStream(file);
profilePic.compress(Bitmap.CompressFormat.PNG, 90, out);
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
return id;
}
#Override
protected void onPreExecute()
{
try
{
img_value = new URL("http://graph.facebook.com/"+id+"/picture?type=" + type);
}
catch (MalformedURLException e) {
e.printStackTrace();
}
}
#Override
protected void onPostExecute(String result) {
}
}
and then I just call:
new DownloadProfilePicTask(id,type).execute();
to download and automatically save images.
Note: You will have to play with filePath a bit for exact location.
There some changes in the fileSystem on Android 4.3 to start to avoid dev. to directly write in "/sdcard" or "/mnt/sdcard" but use the android ExternalStorage system. (http://source.android.com/devices/tech/storage/index.html)
N.B. : ExternalStorage can be an internal memory :p
For your case, have you tryed to use a method based on getExternalStorage ?
(like this : Find an external SD card location)
Related
I am writing a new Application on Android 11 (SDK Version 30) and I simply cannot find an example on how to save a file to the external storage.
I read their documentation and now know that they basicly ignore Manifest Permissions (READ_EXTERNAL_STORAGE and WRITE_EXTERNAL_STORAGE). They also ignore the android:requestLegacyExternalStorage="true" in the manifest.xml application tag.
In their documentation https://developer.android.com/about/versions/11/privacy/storage they write you need to enable the DEFAULT_SCOPED_STORAGE and FORCE_ENABLE_SCOPED_STORAGE flags to enable scoped storage in your app.
Where do I have to enable those?
And when I've done that how and when do I get the actual permission to write to the external storage? Can someone provide working code? I want to save .gif, .png and .mp3 files. So I don't want to write to the gallery.
Thanks in advance.
Corresponding To All Api, included Api 30, Android 11 :
public static File commonDocumentDirPath(String FolderName)
{
File dir = null;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R)
{
dir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS) + "/" + FolderName);
}
else
{
dir = new File(Environment.getExternalStorageDirectory() + "/" + FolderName);
}
// Make sure the path directory exists.
if (!dir.exists())
{
// Make it, if it doesn't exit
boolean success = dir.mkdirs();
if (!success)
{
dir = null;
}
}
return dir;
}
Now, use this commonDocumentDirPath for saving file.
A side note from comments, getExternalStoragePublicDirectory with certain scopes are now working with Api 30, Android 11. Cheers! Thanks to CommonsWare hints.
You can save files to the public directories on external storage.
Like Documents, Download, DCIM, Pictures and so on.
In the usual way like before version 10.
**Simplest Answer and Tested ( Java ) **
private void createFile(String title) {
Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("text/html");
intent.putExtra(Intent.EXTRA_TITLE, title);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
intent.putExtra(DocumentsContract.EXTRA_INITIAL_URI, Uri.parse("/Documents"));
}
createInvoiceActivityResultLauncher.launch(intent);
}
private void createInvoice(Uri uri) {
try {
ParcelFileDescriptor pfd = getContentResolver().
openFileDescriptor(uri, "w");
if (pfd != null) {
FileOutputStream fileOutputStream = new FileOutputStream(pfd.getFileDescriptor());
fileOutputStream.write(invoice_html.getBytes());
fileOutputStream.close();
pfd.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
/////////////////////////////////////////////////////
// You can do the assignment inside onAttach or onCreate, i.e, before the activity is displayed
String invoice_html;
ActivityResultLauncher<Intent> createInvoiceActivityResultLauncher;
#Override
protected void onCreate(Bundle savedInstanceState) {
invoice_html = "<h1>Just for testing received...</h1>";
createInvoiceActivityResultLauncher = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
result -> {
if (result.getResultCode() == Activity.RESULT_OK) {
// There are no request codes
Uri uri = null;
if (result.getData() != null) {
uri = result.getData().getData();
createInvoice(uri);
// Perform operations on the document using its URI.
}
}
});
I'm using this method and it really worked for me
I hope I can help you. Feel free to ask me if something is not clear to you
Bitmap imageBitmap;
OutputStream outputStream ;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
{
ContentResolver resolver = context.getContentResolver();
ContentValues contentValues = new ContentValues();
contentValues.put(MediaStore.MediaColumns.DISPLAY_NAME,"Image_"+".jpg");
contentValues.put(MediaStore.MediaColumns.MIME_TYPE,"image/jpeg");
contentValues.put(MediaStore.MediaColumns.RELATIVE_PATH,Environment.DIRECTORY_PICTURES + File.separator+"TestFolder");
Uri imageUri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,contentValues);
try {
outputStream = resolver.openOutputStream(Objects.requireNonNull(imageUri) );
imageBitmap.compress(Bitmap.CompressFormat.JPEG,100,outputStream);
Objects.requireNonNull(outputStream);
Toast.makeText(context, "Image Saved", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(context, "Image Not Not Saved: \n "+e, Toast.LENGTH_SHORT).show();
e.printStackTrace();
}
}
manifest file (Add Permission)
<uses-permission android:name="android.permission.ACCESS_MEDIA_LOCATION" />
I want to implement functionality for saving image in Downloads directory and after that offer to user to open this one in a directory (open directory in which user can find and open this image). But I've got one issue. Saving ends successfully, but when user clicks "OPEN" in snackbar and chooses app to perform this action another directory appears. It contains also "Downloads" directory as well, this Downloads directory does not contain saved images! It seems like in android we have two different "Downloads" directories.
Below is how i get path for save image:
private File getFileForImageSaving() {
String filename = getImageNameFromUrl(mImageUrl) + ".png";
File dest = new File(
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
filename);
int index = 1;
while (dest.exists()) {
filename = getImageNameFromUrl(mImageUrl) + "_" + index + ".png";
dest = new File(
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),
filename);
index++;
}
return dest;
}
This is how i run activity for view "Download" directory and open files.
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
Uri uri = Uri.parse(
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).getPath());
intent.setDataAndType(uri, "image/png");
startActivity(Intent.createChooser(intent, "Open folder"));
This is how I save image. It is realy works, I've checked.
pri
vate void saveImageToFile() {
File dest = getFileForImageSaving();
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
FileOutputStream out = null;
try {
dest.createNewFile();
out = new FileOutputStream(dest);
Bitmap bitmap = Glide.with(ArticleImageViewActivity.this)
.load(mImageUrl)
.asBitmap()
.into(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)
.get();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
out.flush();
Utils.showInSnackBar(
ArticleImageViewActivity.this, getString(R.string.image_has_been_successfully_saved),
Snackbar.LENGTH_LONG,
onOpenImageInDirectoryListener,
getString(R.string.open_image_in_directory));
} catch (Exception e) {
Utils.showInSnackBar(ArticleImageViewActivity.this,
getString(R.string.error_occurred_during_saving_image),
Snackbar.LENGTH_SHORT, null, null);
} finally {
if (out != null) {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return null;
}
}.execute();
}
I partially resolve my problem by using Intent.ACTION_VIEW instead of Intent.ACTION_GET_CONTENT and " / " mime type instead of "image/png". But only partially because in this case user will be offered to choose a wide range of applications, but not only applications like filemanagers.
use MediaScannerConnection.scanFile to scan the file after saving. if you don't many/most galleries wont show your file.
https://developer.android.com/reference/android/media/MediaScannerConnection.html
My app should save files to a place where, when you connect your phone/tablet to a computer, you can see them through the system file explorer.
This is the way I implemented file writing:
protected String mDir = Environment.DIRECTORY_DOCUMENTS;
protected File mPath = Environment.getExternalStoragePublicDirectory(mDir);
protected void writeLogFile(String filename) {
File f = new File(mPath, filename + ".txt");
f.getParentFile().mkdirs();
try (BufferedWriter bw = new BufferedWriter(new FileWriter(f, false))) {
// Details omitted.
} catch (Exception e) {
e.printStackTrace();
return;
}
makeText("Wrote " + f.getAbsolutePath());
}
This is what I see when I connect my Sony Xperia Z4 tablet to Windows (notice missing documents folder):
This is the directory to which the file is written (using above implementation):
What is wrong with my implementation?
What is wrong with my implementation?
MediaStore has not discovered your newly-created files yet. What you see in Windows — and in many on-device "gallery" apps — is based on what MediaStore has indexed.
Use MediaScannerConnection and its scanFile() method to tell MediaStore about your file, once you have written out your data to disk:
public void scanFile(Context ctxt, File f, String mimeType) {
MediaScannerConnection
.scanFile(ctxt, new String[] {f.getAbsolutePath()},
new String[] {mimeType}, null);
}
or, in Kotlin:
fun scanFile(ctxt: Context, f: File, mimeType: String) {
MediaScannerConnection.scanFile(ctxt, arrayOf(f.getAbsolutePath()), arrayOf(mimeType), null)
}
I want to create a XML file inside my Android app.
This file I want to write into the documents folder of my Android device.
Later I want to connect my Android device to my PC using USB and read that XML file out of the documents folder.
My Device is an Android Galaxy Tab Pro 10.1, Android 4.4.2.
I tried already:
String fileName = "example.xml";
String myDirectory = "myDirectory";
String externalStorage = Environment.getExternalStorageDirectory().getAbsolutePath();
File outputFile = new File(externalStorage + File.separator + myDirectory + File.separator + fileName);
But no file is created. I also want later to read that file out of the documents folder into may app again.
Any help is appreciated, thanks!
I know this is late, but you can get the documents directory like this:
File dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS);
File file = new File(dir, "example.txt");
//Write to file
try (FileWriter fileWriter = new FileWriter(file)) {
fileWriter.append("Writing to file!");
} catch (IOException e) {
//Handle exception
}
Set permission in Android Manifest
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Use this code to write to external directory
String fileName = "example.xml";
String dirName = "MyDirectory";
String contentToWrite = "Your Content Goes Here";
File myDir = new File("sdcard", dirName);
/*if directory doesn't exist, create it*/
if(!myDir.exists())
myDir.mkdirs();
File myFile = new File(myDir, fileName);
/*Write to file*/
try {
FileWriter fileWriter = new FileWriter(myFile);
fileWriter.append(contentToWrite);
fileWriter.flush();
fileWriter.close();
}
catch(IOException e){
e.printStackTrace();
}
Before creating file you have to create directory in which you are saving the file.
Try like this one:-
String fileName = "example.xml";
String myDirectory = "myDirectory";
String externalStorage = Environment.getExternalStorageDirectory().getAbsolutePath();
File outputDirectory = new File(externalStorage + File.separator + myDirectory );
if(!outputDirectory.exist()){
outputDirectory.mkDir();
}
File outputFile = new File(externalStorage + File.separator + myDirectory + File.separator + fileName);
outputFile.createFile();
Try restarting you device and then check if the file exists. If so, you are creating it (which it looks like you should be based on your code) but it is not showing up until the media is scanned on your device. Try implementing MediaScannerConnectionClient so it will show become visible after creation.
public class MainActivity extends Activity implements MediaScannerConnectionClient {
private MediaScannerConnection msConn;
private File example;
...
#Override
protected void onCreate(Bundle savedInstanceState) {
...
msConn = new MediaScannerConnection(this.getApplicationContext(), this);
String dir = Environment.getExternalStorageDirectory() + "/Documents/";
example = new File(dir, "example.xml");
msConn.connect();
}
#Override
public void onMediaScannerConnected() {
msConn.scanFile(example.getAbsolutePath(), null);
}
#Override
public void onScanCompleted(String path, Uri uri) {
msConn.disconnect();
}
From Android 10 onwards, Android started using Scoped Storage model to protect user privacy.
If you want to share this file with the User, then you should write this file in Shared Storage. To write a file in Shared Storage, this has to be done in 3 steps:-
Step 1: Launch System Picker to choose the destination by the user. This will return Uri of the destination directory.
private ActivityResultLauncher<Intent> launcher; // Initialise this object in Activity.onCreate()
private Uri baseDocumentTreeUri;
public void launchBaseDirectoryPicker() {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
launcher.launch(intent);
}
Step 2: Launch System Picker to choose the destination by the user. This will return the Uri of the destination directory. Also, you can optionally persist the permissions and Uri for future use.
#Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
baseDocumentTreeUri = Objects.requireNonNull(result.getData()).getData();
final int takeFlags = (Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
// take persistable Uri Permission for future use
context.getContentResolver().takePersistableUriPermission(result.getData().getData(), takeFlags);
SharedPreferences preferences = context.getSharedPreferences("com.example.fileutility", Context.MODE_PRIVATE);
preferences.edit().putString("filestorageuri", result.getData().getData().toString()).apply();
} else {
Log.e("FileUtility", "Some Error Occurred : " + result);
}
}
Step 3: Write CSV content into a file.
public void writeFile(String fileName, String content) {
try {
DocumentFile directory = DocumentFile.fromTreeUri(context, baseDocumentTreeUri);
DocumentFile file = directory.createFile("text/*", fileName);
ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(file.getUri(), "w");
FileOutputStream fos = new FileOutputStream(pfd.getFileDescriptor());
fos.write(content.getBytes());
fos.close();
} catch (IOException e) {
}
}
For more explanation, you can read "How to Save a file in Shared Storage in Android 10 or Higher" or Android official documentation.
///edited
I try to run the program on the main thread and it can read and save.
I think is problem of the asynctask!!
///
First I already add the user permission to the android manifest
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
I try to read a raw image data from mnt/sdcard/Bluetooth and process it and then write to the internal sdcard and the write path is mnt/sdcard/Bluetooth.
The program can run in my android emulator and save File.
However,when run it real phone, it seems that the phone can only read my file,but not save file.
public class MainActivity extends Activity {
String filenameIn ="ardrone.raw";
File file = new File(Environment.getExternalStorageDirectory()+"/Bluetooth/", filenameIn);
String filename ="convertA.jpg";
File outputfile = new File(Environment.getExternalStorageDirectory() +"/Bluetooth/",filename);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myImageView = (ImageView)findViewById(R.id.imageView);
Toast.makeText(this, "search raw file", Toast.LENGTH_LONG).show();
new imageProcess().execute();
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,Uri.parse("file://" + Environment.getExternalStorageDirectory())));
Bitmap myBitmap = BitmapFactory.decodeFile(Environment.getExternalStorageDirectory()
.getAbsolutePath()+"/Bluetooth/convertA.jpg");
myImageView.setImageBitmap(myBitmap);
if (file.exists()){
Toast.makeText(this, "InFile:)", Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(this, "InFile:(((((", Toast.LENGTH_LONG).show();
}
if (outputfile.exists()){
Toast.makeText(this, "outputfile:)", Toast.LENGTH_LONG).show();
}
else{
Toast.makeText(this, "outputfile:(((((", Toast.LENGTH_LONG).show();
}
}
public class imageProcess extends AsyncTask<String, Integer, Boolean>{
Boolean check_point= false;
#Override
protected Boolean doInBackground(String... arg0) {
try {
receiveVideoRawData();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
}
public void receiveVideoRawData() throws IOException{
byte[] buf_rcv = new byte[153600];
ByteArrayOutputStream ous = new ByteArrayOutputStream();
InputStream ios = new FileInputStream(file);
int read = 0;
while ( (read = ios.read(buf_rcv)) != -1 ) {
ous.write(buf_rcv, 0, read);
}
ous.close();
ios.close();
ReadRawFileImage readMyRawData=new ReadRawFileImage();
image = readMyRawData.readUINT_RGBImage(buf_rcv);
//transfer data
OutputStream _outStream = new FileOutputStream(outputfile);
Bitmap pBitmap = image ;
pBitmap.compress(Bitmap.CompressFormat.JPEG, 90, _outStream);
_outStream.flush();
_outStream.close();
}
}
The first thing is to check if your path exists; on different phones the sd card may be mounted at different locations. On my Linux,
$ ~/android-sdk-linux/platform-tools/adb shell ls -l /mnt/sdcard/
The 2nd thing is to check permissions on the file and the containing directory.
Then, you might examine the logs (they may already contain an error message); then, add debug output to your code and examine the logs with that debug output.
try making your new file writable using file.writable(true). It could also be that your new file doesnt really exist.
Apparently you only need to set the external read permission if you don't have the write permission, this might be overwriting your write privileges?
http://developer.android.com/reference/android/Manifest.permission.html#READ_EXTERNAL_STORAGE
First you should confirm that the real device has SDCARD storage(Some device have not "SDCARD" storage).
Please see below reference to get all storage list
How to list additional external storage folders (mount points)?