PCLStorage - How to get path to writable folder? - xamarin

I need download and save file. I using this code (with Xam.Plugins.DownloadManager and PCLStorage libraries):
public static string DownloadNewXml(string LinkToFile, string PathFile)
{
var downloadManager = CrossDownloadManager.Current;
CrossDownloadManager.Current.PathNameForDownloadedFile = new System.Func<IDownloadFile, string>(file => {
return PathFile;
});
try
{
var file = downloadManager.CreateDownloadFile(LinkToFile);
downloadManager.Start(file);
return "ok";
}
catch(Exception e)
{
return e.ToString() ;
}
}
Where PathFile is: FileSystem.Current.LocalStorage.Path + "file.xml";
This code throw exception on Android and UWP - i can't write file to this path (FileSystem.Current.LocalStorage.Path). So I have a question. How to get path to writable folder for my application on all platforms (Android, UWP, iOS)? Please help.

Try use Path.Combine(FileSystem.Current.LocalStorage.Path, "file.xml") instead

Related

Saving an image to a newly created folder with Uri?

The app i am creating is supposed to save a picture in a sub folder of the pictures folder. As long as i save the picture to the base folder it works fine, but it returns an error as soon as i try to target the subfolder. Permission for writing/reading external storage are given. Do i need to create the folder another way to use it? How do i get the URI of the folder itself?
The error for v1 is: "Failed to write destination file".
The error for v2 is: "Unknown or unsupported URL:content://media/external/images/media/ProxF/"
private void captureImage(ImageCapture imageCapture)
{
//Folder
File dir = new File(getExternalStoragePublicDirectory(DIRECTORY_PICTURES) +"/ProxF");
try{
if(dir.mkdir()) {
System.out.println("Directory created");
} else {
System.out.println("Directory is not created");
}
}catch(Exception e){
e.printStackTrace();
}
//MEDIA API
String FotoString="picture1";
ContentValues contentValues=new ContentValues();
contentValues.put(MediaStore.MediaColumns.DISPLAY_NAME, FotoString);
contentValues.put(MediaStore.MediaColumns.MIME_TYPE, "image/jpeg");
//Saving to the picture folder - working
Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
//V1 - not working
File folder = new File(getExternalStoragePublicDirectory(DIRECTORY_PICTURES).toString() + "/ProxF/");
Uri uri1=Uri.fromFile(folder);
//V2 - not working
Uri uri2 = Uri.parse(MediaStore.Images.Media.EXTERNAL_CONTENT_URI+"/ProxF/")
ImageCapture.OutputFileOptions fileOptions= new ImageCapture.OutputFileOptions.Builder(getContentResolver(),uri,contentValues).build();
imageCapture.takePicture(fileOptions, Executors.newCachedThreadPool(), new ImageCapture.OnImageSavedCallback() {
#Override
public void onImageSaved(#NonNull ImageCapture.OutputFileResults outputFileResults) {
runOnUiThread(() -> Toast.makeText(KameraAc.this, "Image Saved ",Toast.LENGTH_SHORT).show());
startCamera();
}
#Override
public void onError(#NonNull ImageCaptureException exception) {
runOnUiThread(() -> Toast.makeText(KameraAc.this, "Failed to save: "+exception.getMessage(), Toast.LENGTH_SHORT).show());
startCamera();
}
});
}

VS UnitTesting a FileContentResult - Can I generate the file when testing

I want to Unit Test a method that returns a FileContentResult of a PDF file. I am doing some tests to check the content type & file name, but it would be great if I could also generate the PDF somehow as part of the test? I currently have a method as follows:
public FileContentResult ConvertToPDF(int baseClassId)
{
try
{
return new DocumentWriter().ConvertDocumentToPDFSharp(baseClassId);
}
catch (Exception ex)
{
Logger.Instance.LogError("Error in Assessments_FormHeaderController ConvertToPDF", ex);
return new FileContentResult(GetBytes("Error fetching pdf, " + ex.Message + Environment.NewLine + ex.StackTrace), "text/plain");
}
}
and I am testing with the following:
[TestMethod]
public void ReturnFileContentResult()
{
DocumentPDFPrinterController pdfController = new DocumentPDFPrinterController();
FileContentResult result = pdfController.ConvertToPDF(0);
Assert.IsTrue(result.ContentType == "application/pdf" && result.FileDownloadName.Contains(".pdf"));
}
Can I add anything to this text which will create the pdf file in a given location(user downloads?).
Should have done some more investigating before putting the question out there. I have found simply adding the following got the job done for me:
System.IO.File.WriteAllBytes(#"C:\Users\username\Downloads\Test.pdf", result.FileContents);
That generates my file nicely.

Xamarin Forms - calling rest service from viewmodel of pcl

I created a class that connected to the API to retrieve the required data using httpclient. That file was called in the code behind file of the view and worked perfectly. Than I decided to implement the MVVM approach. As a result, I moved the code that initialized the rest service class to the view-model.
After doing that, i stopped getting the data. To investigate, I stated the the debugging session with the breakpoint placed at the line where i initialize the rest service class. Than i executed that line. By doing that, I found out that a huge android mono exception is thrown and the debugging session if stopped. The app exits the debugging session.
This has happened for the first time since i stated developing my app in Xamarin Forms. I have no idea about why it is breaking like that. Your help will be greatly appreciated.
This is the code that was working properly.
In the view code behind file
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class SubtaskPage : ContentPage
{
protected override void OnAppearing()
{
base.OnAppearing();
PopulateSubtaskData();
}
private async void PopulateSubtaskData()
{
lstSubtasks.IsRefreshing = true;
try
{
RestService rs = new RestService();
SResponse = await rs.GetSubtasksAsync(Convert.ToInt32(Application.Current.Properties["UserId"]));
if (SResponse.Status == 1)
{
lstSubtasks.ItemsSource = SResponse.Subtasks;
}
else
{
await DisplayAlert("Error", SResponse.Message, "Ok");
}
}
catch (Exception E)
{
Debug.WriteLine(#"GetSubtasksAsync -> ERROR {0}", E.Message);
}
lstSubtasks.IsRefreshing = false;
}
}
The rest service class is as follows
This class is in a separate folder named "Services". ip and url have been changed for security reason.
class RestService
{
HttpClient client;
public List<Ticket> Tickets { get; private set; }
string Server1 = "server ip";
string Server2 = "server ip";
public RestService()
{
client = new HttpClient();
client.MaxResponseContentBufferSize = 256000;
}
public async Task<SubtasksResponse> GetSubtasksAsync(int UserId)
{
SubtasksResponse SubtaskResponse = new SubtasksResponse();
string ApiUrl = "URL";
string Url = "";
HttpResponseMessage response;
if (CrossConnectivity.Current.IsConnected)
{
Url = await GetActiveServerAsync();
if (Url != "")
{
var uri = string.Format(Url + ApiUrl, UserId);
try
{
response = await client.GetAsync(uri);
if (response.IsSuccessStatusCode)
{
var content = await response.Content.ReadAsStringAsync();
SubtaskResponse.Subtasks = JsonConvert.DeserializeObject<List<Ticket>>(content);
SubtaskResponse.Status = 1;
}
else
{
SubtaskResponse.Subtasks = null;
SubtaskResponse.Status = 0;
SubtaskResponse.Message = "Attempt to fetch data from server was unsuccessful. Please try again";
}
}
catch (Exception E)
{
SubtaskResponse.Subtasks = null;
SubtaskResponse.Status = 0;
SubtaskResponse.Message = "Error occured while fetching data from the server. Please try again";
}
}
else
{
SubtaskResponse.Subtasks = null;
SubtaskResponse.Status = 0;
SubtaskResponse.Message = "Remote Server Not Responding! Please try again later";
}
}
else
{
SubtaskResponse.Subtasks = null;
SubtaskResponse.Status = 0;
SubtaskResponse.Message = "No Network Connection Found! Please connect to a network and try again";
}
return SubtaskResponse;
}
}
}
This was working fine until I added the view model into the mix.
This is how I am calling the function in the view model.
async Task<SubtasksResponse> PopulateSubtaskList()
{
RestService rs = new RestService();
IsBusy = true;
_subtaskList = await rs.GetSubtasksAsync(Convert.ToInt32(Application.Current.Properties["UserId"]));
IsBusy = false;
return _subtaskList;
}
"RestService rs = new RestService();" this is the line where the code breaks.
Here is the image of the exception that occurs when the code breaks.
Hope you get the clear picture of the situation. Please let me know if additional information is required.
Thanks
Don't do this. If you want to call rest from a mvvm Xamarin Forms app I can advice Refit. All the difficult work is already done for you and abstracted away. With a few lines of code you are up and running.
BTW the error message you are showing probably has nothing to do with your code but is a bug in a recent Xamarin version. See here: https://bugzilla.xamarin.com/show_bug.cgi?id=56787
Found the answer on this page (https://releases.xamarin.com/common-issues-in-the-xamarin-15-2-2-release-being-tracked-by-the-xamarin-team/).
The solution is as follows
Download the missing Mono.Posix file and unzip the archive.
Right-click the Mono.Posix.dll file in Explorer and select Properties.
Check the Digital Signatures tab to ensure the file shows a valid Xamarin Inc. signature.
At the bottom of the General tab, if an Unblock checkbox appears, enable it and select OK. (This checkbox appears depending on how the file was downloaded.)
For Visual Studio 2017, copy the Mono.Posix.dll file into the “Xamarin.VisualStudio” extension directory. For example, for a default installation of the Enterprise edition, copy the file into:
C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\Extensions\Xamarin.VisualStudio
For Visual Studio 2015, copy the file into the “Xamarin\Xamarin” extension directory:
C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\Extensions\Xamarin\Xamarin\
Quit and restart Visual Studio.
For more detail, visit the link given above.

Unable to load DLL 'e_sqlite3': The specified module could not be found

I have a Xamarin Forms solution. I added sqlite-net-pcl as reference to all projects. It works fine on Android but crashes on Windows 8.1 and Windows Phone 8.1. I have an IOS project but I don't have OSX at the moment to try it.
I use this in the Windows projects to access the database:
using System.IO;
using SQLite;
using Xamarin.Forms;
using HelloXamarin.Windows;
using Windows.Storage;
[assembly: Dependency(typeof(SQLiteDb))]
namespace HelloXamarin.Windows
{
public class SQLiteDb : ISQLiteDb
{
public SQLiteAsyncConnection GetConnection(string databaseName)
{
var documentsPath = ApplicationData.Current.LocalFolder.Path;
var path = Path.Combine(documentsPath, databaseName);
return new SQLiteAsyncConnection(path);
}
}
}
Here are my references:
I get this exception when trying to access the database:
The type initializer for 'SQLite.SQLiteConnection' threw an exception.
Unable to load DLL 'e_sqlite3': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
at SQLitePCL.SQLite3Provider_e_sqlite3.NativeMethods.sqlite3_win32_set_directory(UInt32 directoryType, String directoryPath)
at SQLitePCL.SQLite3Provider_e_sqlite3..ctor()
at SQLitePCL.Batteries_V2.Init() at SQLite.SQLiteConnection..cctor()
I have no idea how to solve this, please help me!
The whole solution is available on GitHub:
https://github.com/apspot/HelloXamarin
For me, it worked by adding the e_sqlite3 bundle to the executable project
By this time the issue is still open. So before they come with some solid fix, you can use this work around, to solve the issue for now.
Add one helper class
using System;
using System.Diagnostics;
using System.IO;
namespace SQLitePCL
{
public class NativeLibraryHack
{
public static bool Hacked { get; private set; }
public static bool DoHack()
{
if (Hacked) return true;
try
{
const string runtimeFolderName = "/runtimes";
var destinationPath = typeof(SQLitePCL.raw).Assembly.Location
.Replace("\\", "/");
var destinationLength = destinationPath.LastIndexOf("/", StringComparison.OrdinalIgnoreCase);
var destinationDirectory = destinationPath.Substring(0, destinationLength) + runtimeFolderName;
var sourcePath = new Uri(typeof(SQLitePCL.raw).Assembly.CodeBase)
.AbsolutePath;
var sourceLength = sourcePath.LastIndexOf("/", StringComparison.OrdinalIgnoreCase);
var sourceDirectory = sourcePath.Substring(0, sourceLength) + runtimeFolderName;
if (Directory.Exists(sourceDirectory))
CopyFilesRecursively(new DirectoryInfo(sourceDirectory), new DirectoryInfo(destinationDirectory));
}
catch (Exception ex)
{
//Ignore Exception
Debug.WriteLine(ex.Message);
return false;
}
return (Hacked = true);
}
private static void CopyFilesRecursively(
DirectoryInfo source,
DirectoryInfo target
)
{
foreach (var dir in source.GetDirectories())
CopyFilesRecursively(dir, target.CreateSubdirectory(dir.Name));
foreach (var file in source.GetFiles())
{
try
{
var destinationFile = Path.Combine(target.FullName, file.Name);
if (!File.Exists(destinationFile))
file.CopyTo(destinationFile);
}
catch (Exception ex)
{
//Ignore Exception
Debug.WriteLine(ex.Message);
}
}
}
}
}
And add the hack before your db migration script, I am using web api 2
so i did on RouteConfig.RegisterRoutes
NativeLibraryHack.DoHack();
using (KSDBContext db = new KSDBContext())
{
db.Database.Migrate();
}
You need to add the SQLite Extensions.
Go to Tools > Extensions and Updates
Go to Online, then search for SQLite.
Download SQLite for Windows Runtime
In your Windows Project, Add Reference and ensure you add the extension.
Also remove Microsoft.VCLibs from your references.
Try referencing Visual C++ 2015 Runtime for Universal Windows Platform Apps. That sorted it out for me.
Go to References
Add Reference
Extensions.
Check"Visual C++ 2015 Runtime for Universal Windows Platform Apps"
OK

sub folder in not creating on azure in asp.net mvc5 application

I am ruing my website on azure, every folder is present on site directory in azure but uploadimages is my sub folder of content is absent from wwwroot, and images is not uploading also
I am using
var path =Path.Combine(Server.MapPath("~/Content/UploadImages/")+filename);
same with document upload
According to your description, I have tested on my side, please follow below to find out whether it could help you.
As you said, you got the target file path by this code:
var path = Path.Combine(Server.MapPath("~/Content/UploadImages/") + filename);
Before uploading files, please make sure that the directory in your web server “~/Content/UploadImages/” is existed.
Here is my test code:
MVC controller method
[HttpPost]
public JsonResult UploadFiles()
{
try
{
foreach (string file in Request.Files)
{
var fileContent = Request.Files[file];
if (fileContent != null && fileContent.ContentLength > 0)
{
var stream = fileContent.InputStream;
var fileName = Path.GetFileName(fileContent.FileName);
string baseDir = Server.MapPath("~/Content/UploadImages/");
if (!Directory.Exists(baseDir))
Directory.CreateDirectory(baseDir);
var path = Path.Combine(baseDir, fileName);
using (var fileStream = System.IO.File.Create(path))
{
stream.CopyTo(fileStream);
}
}
}
}
catch (Exception e)
{
return Json(new
{
Flag = false,
Message = string.Format("File Uploaded failed with exception:{0}", e.Message)
});
}
return Json(new
{
Flag = true,
Message = "File uploaded successfully!"
});
}
Additionally, for long-term consideration, you could store your files on Azure Blob Storage which could bring you some benefits, such as:
1.Serving images or documents directly to a browser
2.Storing files for distributed access
3.When you scale up your site, your site could run in multiple Web Server instances which could access the same files & docs simultaneously
For more details, please refer to this link: https://azure.microsoft.com/en-us/documentation/articles/storage-dotnet-how-to-use-blobs/

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