I am developing a Xamarin app which retrives info from DB, take/choose photo and upload them to remote server, display this images from the remote server and the user can delete them by tap on and press a button and download the images from the remote server to the local device.
Everything works without problem, but when I download the image and after I go to the gallery for check it, the image does not appear, whereas I can see it and open in the file explorer. When I reboot the phone, the image appear in the gallery.
Below my current button download method:
private void button_download_image_Clicked(object sender, EventArgs e)
{
Uri image_url_format = new Uri(image_url);
WebClient webClient = new WebClient();
try
{
byte[] bytes_image = webClient.DownloadData(image_url_format);
Stream image_stream = new MemoryStream(bytes_image);
string dest_folder = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryDownloads).ToString();
string file_name = System.IO.Path.GetFileName(image_url_format.LocalPath);
string dest_path = System.IO.Path.Combine(dest_folder, file_name);
using (var fileStream = new FileStream(dest_path, FileMode.Create, FileAccess.Write))
{
image_stream.CopyTo(fileStream);
}
}
catch (Exception ex)
{
DisplayAlert("Error", ex.ToString(), "OK");
}
DisplayAlert("Alert", "Download completed!", "OK");
}
I tried in another device, but I got the same behavior.
Probably there is a sort of thing which does not refresh the gallery.
Any idea how to force the gallery to refresh or something similar?
You need to refresh your gallery after inserting or deleting any pictures in storage.
You can try this.
var mediaScanIntent = new Intent(Intent.ActionMediaScannerScanFile);
mediaScanIntent.SetData(Android.Net.Uri.FromFile(new Java.IO.File(dest_path)));
Xamarin.Forms.Forms.Context.SendBroadcast(mediaScanIntent);
Add these lines below your code.
Make it like
private void button_download_image_Clicked(object sender, EventArgs e)
{
Uri image_url_format = new Uri(image_url);
WebClient webClient = new WebClient();
try
{
byte[] bytes_image = webClient.DownloadData(image_url_format);
Stream image_stream = new MemoryStream(bytes_image);
string dest_folder = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryDownloads).ToString();
string file_name = System.IO.Path.GetFileName(image_url_format.LocalPath);
string dest_path = System.IO.Path.Combine(dest_folder, file_name);
using (var fileStream = new FileStream(dest_path, FileMode.Create, FileAccess.Write))
{
image_stream.CopyTo(fileStream);
}
var mediaScanIntent = new Intent(Intent.ActionMediaScannerScanFile);
mediaScanIntent.SetData(Android.Net.Uri.FromFile(new Java.IO.File(dest_path)));
//for old xamarin forms version
Xamarin.Forms.Forms.Context.SendBroadcast(mediaScanIntent);
//for new xamarin forms version
//Android.App.Application.SendBroadcast(mediaScanIntent);
}
catch (Exception ex)
{
DisplayAlert("Error", ex.ToString(), "OK");
return;
}
DisplayAlert("Alert", "Download completed!", "OK");
}
You need to just refresh the file you have downloaded. It's helpful.
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT){
Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
File f = new File("file://"+ Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES));
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}else{
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://" + Environment.getExternalStorageDirectory())));
}
Make sure required permission given on both platforms.
Use in your class:
bool success = await DependencyService.Get<IPhotoLibrary>().SavePhotoAsync(data, folder, filename);
Common Interface
public interface IPhotoLibrary
{
Task<bool> SavePhotoAsync(byte[] data, string folder, string filename);
}
In Android service
public async Task<bool> SavePhotoAsync(byte[] data, string folder, string filename)
{
try
{
File picturesDirectory = Environment.GetExternalStoragePublicDirectory(Environment.DirectoryPictures);
File folderDirectory = picturesDirectory;
if (!string.IsNullOrEmpty(folder))
{
folderDirectory = new File(picturesDirectory, folder);
folderDirectory.Mkdirs();
}
using (File bitmapFile = new File(folderDirectory, filename))
{
bitmapFile.CreateNewFile();
using (FileOutputStream outputStream = new FileOutputStream(bitmapFile))
{
await outputStream.WriteAsync(data);
}
// Make sure it shows up in the Photos gallery promptly.
MediaScannerConnection.ScanFile(MainActivity.Instance,
new string[] { bitmapFile.Path },
new string[] { "image/png", "image/jpeg" }, null);
}
}
catch (System.Exception ex)
{
return false;
}
return true;
}
In iOS service:
public Task<bool> SavePhotoAsync(byte[] data, string folder, string filename)
{
NSData nsData = NSData.FromArray(data);
UIImage image = new UIImage(nsData);
TaskCompletionSource<bool> taskCompletionSource = new TaskCompletionSource<bool>();
image.SaveToPhotosAlbum((UIImage img, NSError error) =>
{
taskCompletionSource.SetResult(error == null);
});
return taskCompletionSource.Task;
}
also you can refer this one just to save an image and to reflect it in media, no need to use skiasharp for that. https://learn.microsoft.com/en-us/xamarin/xamarin-forms/user-interface/graphics/skiasharp/bitmaps/saving
Hope this may resolve your issue.
Refer to Blu's answer,
I changed this Xamarin.Forms.Forms.Context.SendBroadcast(mediaScanIntent); to Android.App.Application.Context.SendBroadcast(mediaScanIntent); and all works.
Related
**sorry for my english but i don't know very well in google translate i do translation.
I want from my listbox the file that I choose to be exported with the same name that it has in my listbox**
private void downloadFile(object sender, EventArgs e)
{
string ip = txt_ip.Text;
string user = txt_user.Text;
string pass = txt_pass.Text;
//string pathLocalFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "download_sftp_file.txt");
try
{
SftpClient client = new SftpClient(ip, user, pass);
client.Connect();
string rmDer = dr_finder.Text;
var files = client.ListDirectory(rmDer);
if (rmDer == "")
{
client.Connect();
string rmDerNow = "/";
var filesName = client.ListDirectory(rmDerNow);
foreach (var file in filesName)
{
DirList.Items.Add(file.Name);
string result = Path.GetFileNameWithoutExtension(file.Name);
DirList.Items.Add(System.IO.Path.GetFileName(file.Name));
}
MessageBox.Show("List Directory Success!");
}
string pachRemFile = DirList.SelectedItem.ToString();
string pachlocalFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop),"Server Ftp File.txt");
Stream Filestream = File.OpenWrite(pachlocalFile);
client.DownloadFile(pachRemFile,Filestream);
client.Disconnect();
}
catch (Exception error)
{
MessageBox.Show(error.Message);
}
}
this object is the solution I finally didn't find anyone to help me. so I helped myself.
and I thought he had good programmers on this site
SaveFileDialog savefile = new SaveFileDialog(); /* this here is my solution get a save as. */
if (savefile.ShowDialog() == DialogResult.OK)
{
string pachRemFile = DirList.SelectedItem.ToString();
Stream Filestream = File.Open(savefile.FileName, FileMode.CreateNew);
StreamWriter sw = new StreamWriter(Filestream);
client.DownloadFile(pachRemFile, Filestream);
client.Disconnect();
}
We have written a code to download images from uri using webclient in xamarin.ios. When we download an image it's not displayed in Gallery/Photo app, or in any other location of the iPhone.
Here is my download code:
public void DownloadFiles()
{
try
{
var webClient = new WebClient();
webClient.DownloadDataCompleted += (s, e) => {
var bytes = e.Result;
string documentsPath = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
string localFilename = "downloaded.png";
string localPath = Path.Combine(documentsPath, localFilename);
Console.WriteLine("localPath:" + localPath);
File.WriteAllBytes(localPath, bytes);
// IMPORTANT: this is a background thread, so any interaction with
// UI controls must be done via the MainThread
InvokeOnMainThread(() => {
// imageView.Image = UIImage.FromFile(localPath);
UIAlertView alert = new UIAlertView()
{
Title = "alert title",
Message = "Download successfully"
};
alert.AddButton("OK");
alert.AddButton("Cancel");
alert.Show();
});
};
var url = new Uri("https://www.xamarin.com/content/images/pages/branding/assets/xamagon.png");
webClient.DownloadDataAsync(url);
}
catch(Exception e)
{
throw e;
}
}
Environment.GetFolderPath(Environment.SpecialFolder.Personal);
how to find this path?
We have added these permission in info.plist to solve this problem. "Privacy - Photo Library Additions Usage Description" and "Privacy - Photo Library Usage Description"
I'm doing a windows phone project, and need to download a text file from the internet and read its content.
This is what I have tried (but it didn't work)
private async Task pobierz()
{
string source = "https://drive.google.com/file/d/0BzgKBwKyU4oORkxxSlVITGswb1E/view?usp=sharing";
string LocalName = "hej.txt";
var srce = new Uri(source, UriKind.Absolute);
// var destinationFile =await KnownFolders.PicturesLibrary.CreateFileAsync()
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(new Uri(#"ms-appx:///Assets/hej.txt"));
var downloader = new BackgroundDownloader();
DownloadOperation download = downloader.CreateDownload(srce,file);
}
Please see https://msdn.microsoft.com/en-us/library/windows/apps/xaml/jj152726.aspx?f=255&MSPPError=-2147217396 for detailed description of how to use the BackgroundDownloader.
You need to implement and call the following method:
private async void HandleDownloadAsync(DownloadOperation download, bool start)
{
try
{
// Store the download so we can pause/resume.
activeDownloads.Add(download);
Progress<DownloadOperation> progressCallback = new Progress<DownloadOperation>(DownloadProgress);
if (start)
{
// Start the download and attach a progress handler.
await download.StartAsync().AsTask(cts.Token, progressCallback);
}
else
{
// The download was already running when the application started, re-attach the progress handler.
await download.AttachAsync().AsTask(cts.Token, progressCallback);
}
ResponseInformation response = download.GetResponseInformation();
Log(String.Format("Completed: {0}, Status Code: {1}", download.Guid, response.StatusCode));
}
catch (TaskCanceledException)
{
Log("Download cancelled.");
}
catch (Exception ex)
{
LogException("Error", ex);
}
finally
{
activeDownloads.Remove(download);
}
}
I am running a program where a file gets uploaded to a folder in IIS,and then is processed to extract some values from it. I use a WCF service to perform the process, and BackgroundUploader to upload the file to IIS. However, after the upload process is complete, I get the error "The process cannot access the file x because it is being used by another process." Based on similar questions asked here, I gathered that the file concerned needs to be in a using statement. I tried to modify my code to the following, but it didn't work, and I am not sure if it is even right.
namespace App17
{
public sealed partial class MainPage : Page, IDisposable
{
private CancellationTokenSource cts;
public void Dispose()
{
if (cts != null)
{
cts.Dispose();
cts = null;
}
GC.SuppressFinalize(this);
}
public MainPage()
{
this.InitializeComponent();
cts = new CancellationTokenSource();
}
public async void Button_Click(object sender, RoutedEventArgs e)
{
try
{
Uri uri = new Uri(serverAddressField.Text.Trim());
FileOpenPicker picker = new FileOpenPicker();
picker.FileTypeFilter.Add("*");
StorageFile file = await picker.PickSingleFileAsync();
using (var stream = await file.OpenAsync(FileAccessMode.Read))
{
GlobalClass.filecontent = file.Name;
GlobalClass.filepath = file.Path;
BackgroundUploader uploader = new BackgroundUploader();
uploader.SetRequestHeader("Filename", file.Name);
UploadOperation upload = uploader.CreateUpload(uri, file);
await HandleUploadAsync(upload, true);
stream.Dispose();
}
}
catch (Exception ex)
{
string message = ex.ToString();
var dialog = new MessageDialog(message);
await dialog.ShowAsync();
Log(message);
}
}
private void CancelAll(object sender, RoutedEventArgs e)
{
Log("Canceling all active uploads");
cts.Cancel();
cts.Dispose();
cts = new CancellationTokenSource();
}
private async Task HandleUploadAsync(UploadOperation upload, bool start)
{
try
{
Progress<UploadOperation> progressCallback = new Progress<UploadOperation>(UploadProgress);
if (start)
{
await upload.StartAsync().AsTask(cts.Token, progressCallback);
}
else
{
// The upload was already running when the application started, re-attach the progress handler.
await upload.AttachAsync().AsTask(cts.Token, progressCallback);
}
ResponseInformation response = upload.GetResponseInformation();
Log(String.Format("Completed: {0}, Status Code: {1}", upload.Guid, response.StatusCode));
cts.Dispose();
}
catch (TaskCanceledException)
{
Log("Upload cancelled.");
}
catch (Exception ex)
{
string message = ex.ToString();
var dialog = new MessageDialog(message);
await dialog.ShowAsync();
Log(message);
}
}
private void Log(string message)
{
outputField.Text += message + "\r\n";
}
private async void LogStatus(string message)
{
var dialog = new MessageDialog(message);
await dialog.ShowAsync();
Log(message);
}
private void UploadProgress(UploadOperation upload)
{
BackgroundUploadProgress currentProgress = upload.Progress;
MarshalLog(String.Format(CultureInfo.CurrentCulture, "Progress: {0}, Status: {1}", upload.Guid,
currentProgress.Status));
double percentSent = 100;
if (currentProgress.TotalBytesToSend > 0)
{
percentSent = currentProgress.BytesSent * 100 / currentProgress.TotalBytesToSend;
}
MarshalLog(String.Format(CultureInfo.CurrentCulture,
" - Sent bytes: {0} of {1} ({2}%), Received bytes: {3} of {4}", currentProgress.BytesSent,
currentProgress.TotalBytesToSend, percentSent, currentProgress.BytesReceived, currentProgress.TotalBytesToReceive));
if (currentProgress.HasRestarted)
{
MarshalLog(" - Upload restarted");
}
if (currentProgress.HasResponseChanged)
{
MarshalLog(" - Response updated; Header count: " + upload.GetResponseInformation().Headers.Count);
}
}
private void MarshalLog(string value)
{
var ignore = this.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
Log(value);
});
}
}
}
After this is done, the file name is sent to a WCF service which will access and process the uploaded file to extract certain values. It is at this point I receive the error. I would truly appreciate some help.
public async void Extract_Button_Click(object sender, RoutedEventArgs e)
{
ServiceReference1.Service1Client MyService = new ServiceReference1.Service1Client();
string filename = GlobalClass.filecontent;
string filepath = #"C:\Users\R\Documents\Visual Studio 2015\Projects\WCF\WCF\Uploads\"+ filename;
bool x = await MyService.ReadECGAsync(filename, filepath);
}
EDIT: Code before I added the using block
try
{
Uri uri = new Uri(serverAddressField.Text.Trim());
FileOpenPicker picker = new FileOpenPicker();
picker.FileTypeFilter.Add("*");
StorageFile file = await picker.PickSingleFileAsync();
GlobalClass.filecontent = file.Name;
GlobalClass.filepath = file.Path;
BackgroundUploader uploader = new BackgroundUploader();
uploader.SetRequestHeader("Filename", file.Name);
UploadOperation upload = uploader.CreateUpload(uri, file);
await HandleUploadAsync(upload, true);
}
When you work with stream writers you actually create a process, which you can close it from task manager. And after stream.Dispose() put stream.Close().
This should solve your problem.
You should also close the stream that writes the file to disk (look at your implementation of CreateUpload).
i got such error in DotNet Core 2 using this code:
await file.CopyToAsync(new FileStream(fullFileName, FileMode.Create));
counter++;
and this is how I managed to get rid of message (The process cannot access the file x because it is being used by another process):
using (FileStream DestinationStream = new FileStream(fullFileName, FileMode.Create))
{
await file.CopyToAsync(DestinationStream);
counter++;
}
I want to add a custom tile to the Microsoft Band through Microsoft Band SDK in a UWP app for Windows Phone. Here is my sample code.
private async void ButtonBase_OnClick(object sender, RoutedEventArgs e)
{
try
{
// Get the list of Microsoft Bands paired to the phone.
var pairedBands = await BandClientManager.Instance.GetBandsAsync();
if (pairedBands.Length < 1)
{
Debug.WriteLine("This sample app requires a Microsoft Band paired to your device.Also make sure that you have the latest firmware installed on your Band, as provided by the latest Microsoft Health app.");
return;
}
// Connect to Microsoft Band.
using (var bandClient = await BandClientManager.Instance.ConnectAsync(pairedBands[0]))
{
// Create a Tile with a TextButton on it.
var myTileId = new Guid("12408A60-13EB-46C2-9D24-F14BF6A033C6");
var myTile = new BandTile(myTileId)
{
Name = "My Tile",
TileIcon = await LoadIcon("ms-appx:///Assets/SampleTileIconLarge.png"),
SmallIcon = await LoadIcon("ms-appx:///Assets/SampleTileIconSmall.png")
};
// Remove the Tile from the Band, if present. An application won't need to do this everytime it runs.
// But in case you modify this sample code and run it again, let's make sure to start fresh.
await bandClient.TileManager.RemoveTileAsync(myTileId);
// Create the Tile on the Band.
await bandClient.TileManager.AddTileAsync(myTile);
// Subscribe to Tile events.
}
}
catch (Exception ex)
{
Debug.WriteLine(ex);
}
}
private async Task<BandIcon> LoadIcon(string uri)
{
StorageFile imageFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri(uri));
using (IRandomAccessStream fileStream = await imageFile.OpenAsync(FileAccessMode.Read))
{
WriteableBitmap bitmap = new WriteableBitmap(1, 1);
await bitmap.SetSourceAsync(fileStream);
return bitmap.ToBandIcon();
}
}
If I run this code nothing happend. The app connected to Microsoft Band, but is not able to add a tile. The method AddTileAsync(myTile); Returns false and doesn't add a tile to the Microsoft Band.
If I try this code in a Windows Phone 8.1 app it works, but not in the UWP app.
Any ideas?
Update
Here is the sample app as download. Maybe this can help.
maybe this would help, coming from the documentation of MS Band
using Microsoft.Band.Tiles;
...
try
{
IEnumerable<BandTile> tiles = await bandClient.TileManager.GetTilesAsync();
}
catch (BandException ex)
{
//handle exception
}
//determine if there is space for tile
try
{
int tileCapacity = await bandClient.TileManager.GetRemainingTileCapacityAsync();
}
catch (BandException ex)
{
//handle ex
}
//create tile
WriteAbleBitmap smallIconBit = new WriteAbleBitmap(24, 24);
BandIcon smallIcon = smallIconBit.ToBandIcon();
WriteAbleBitmap largeIconBit = new WriteAbleBitmap(48, 48);//46, 46 for MS band 1
BandIcon largeIcon = largeIconBit.ToBandIcon();
Guid guid = Guid.NewGuid();
BandTile tile = new BandTile(guid)
{
//enable Badging
IsBadgingEnabled = true,
Name = "MYNAME"
SmallIcon = smallIcon;
TileIcon = largeIcon;
};
try
{
if(await bandClient.TileManager.AddTileAsync(tile))
{
///console print something
}
}
catch(BandException ex)
{
//blabla handle
}
I think the issue may be you're setting the writeable bitmap size to (1,1)?
I have this method working:
public static class BandIconUtil
{
public static async Task<BandIcon> FromAssetAsync(string iconFileName, int size = 24)
{
string uri = "ms-appx:///" + iconFileName;
StorageFile imageFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri(uri, UriKind.RelativeOrAbsolute));
using (IRandomAccessStream fileStream = await imageFile.OpenAsync(FileAccessMode.Read))
{
WriteableBitmap bitmap = new WriteableBitmap(size, size);
await bitmap.SetSourceAsync(fileStream);
return bitmap.ToBandIcon();
}
}
}