Invalid Form.Handle under Linux - winforms

I'am running mono v3.2.8 x64 under ArchLinux (Gnome 3) and noticed this strange behavior when crating a WinForm using this code:
namespace MWFTestApplication {
class MainWindow : System.Windows.Forms.Form {
public MainWindow() {
string hande = string.Format ("0x{0}", Handle.ToString ("x"));
Console.WriteLine("Handle: " + hande);
}
public static void Main(string[] args) {
Application.Run(new MainWindow());
}
}
}
When I execute this under ArchLinux I can see the form but the result is like Handle: 0x200000f which obviously cant be right. I can recompile the application and start it again and the Handle does not change until I reboot. Then I get a new invalid Handle. When I run the same code under Windows I get a new random pointer for each run as expected.
My graphic card is a NVIDIA GTX 690 running driver version 334.21.

Related

Cefsharp Winform shows images blurred

Tools used : .net framework 4.7.2, Windows 7 x64, Visual Studio 2019
I'm creating a Cefsharp Winform browser.
It works as an simple GUI for my asp.net core app.
The problem stands on the fact that the pictures are very blurred.
If i use firefox/chrome the pictures are high quality and clean.
My Form1.cs :
public ChromiumWebBrowser browser;
public void InitBrowser()
{
CefSharpSettings.WcfEnabled = true;
var settings = new CefSettings();
//Absolute path to your applications executable
settings.BrowserSubprocessPath = System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName;
Cef.EnableHighDPISupport();
Cef.RefreshWebPlugins();
Cef.Initialize(new CefSettings());
browser = new ChromiumWebBrowser("https://localhost:5001")
{
MenuHandler = new CustomMenuHandler()
};
this.Controls.Add(browser);
browser.Dock = DockStyle.Fill;
}
public Form1()
{
InitializeComponent();
InitBrowser();
}
the debug_.log :
[0529/224714.592:ERROR:gpu_init.cc(426)] Passthrough is not supported, GL is disabled
[0529/225010.059:WARNING:dns_config_service_win.cc(712)] Failed to read DnsConfig.
What's wrong with this code?

AssemblyLoadContext.Unload does not unload a Wpf Library

I am writing here the same issue posted on Github since I don't see much traffic there recently.
.NET Core Version: 3.1.9 and .Net 5
Windows version: 10.0.18363
Does the bug reproduce also in WPF for .NET Framework 4.8?: AssemblyLoadContext not supported
I am trying to load and unload on demand a Wpf App library (and all the related dependencies). Everything works, but none of the assemblies get unloaded when calling the Unload method.
If I replace the Wpf library with a .Net Core library containing a few sample methods, I can see the library removed from VS Modules window after a couple of GC iterations.
If I'm not wrong I should expect AssemblyLoadContext to load WpfLibrary and related dependencies (PresentationCore, PresentationFramework etc), but WpfLibrary is the only one loaded. All the other dependencies seems be loaded in the default context. May be that I misunderstood how it works, but to me seems that the framework dependencies prevent the unloading.
Also I am not sure if the problem I am reporting is related to this and/or this.
I attached a sample project which is structured like this:
Project 1 (MainApp, a console project with added System.Windows.Forms reference to enable message pump)
class Program
{
class WpfAppAssemblyLoadContext : AssemblyLoadContext
{
public WpfAppAssemblyLoadContext() : base(true) { }
protected override Assembly Load(AssemblyName assemblyName) => null;
}
[MethodImpl(MethodImplOptions.NoInlining),]
public static void TestRun()
{
var context = new WpfAppAssemblyLoadContext();
var assembly = context.LoadFromAssemblyPath($"{Environment.CurrentDirectory}\\WpfLibrary.dll");
var inst = (IProxy) assembly.CreateInstance("WpfLibrary.MainWindow");
inst.ShowWindow();
inst.CloseWindow();
context.Unload();
assembly = null;
context = null;
inst = null;
}
[STAThread,]
static void Main(string[] args)
{
TestRun();
for (var i = 0; i < 100; i++) {
GC.Collect();
GC.WaitForPendingFinalizers();
}
Application.Run();
}
}
Project 2 (ProxyInterface)
namespace ProxyInterface
{
public interface IProxy
{
void ShowWindow();
void CloseWindow();
}
}
Project 3 (a regular wpf library with implementation of interface in Project 2 )
namespace WpfLibrary
{
public partial class MainWindow : Window, IProxy
{
public MainWindow()
{
InitializeComponent();
}
public void ShowWindow() { Show();}
public void CloseWindow() { Close();}
}
}
UnloadWpfLibrary.zip
(Solution file inside "MainApp" folder)
Further updates:
DotNet team added the issue to "Future Milestone", therefore I have to deduce that they recognized this as a bug. I have no idea on when we will see Wpf working with AssemblyLoadContext.
Seems to be that there is a workaround which involve splitting the target assembly into two separate assemblies. I attached the project with the suggested modifications and this time one of the two assemblies is unloaded, but all of the others are still loaded included WpfLibrary.
UnloadWpfLibraryWithWorkaround.zip
I think that for me it's time to give up and recur to IPC (named pipes) although I am not sure if this could be a valid replacement.
May be I missed something and someone more expert can do further progress and attach here the project with the correct modifications, it would be of great benefit for all the users that want to use ALC to load and unload WPF.
It would be a total of 4 projects just to load and unload a wpf assembly on demand and this is not exactly clean, but if the final result is the same it would be acceptable.

Using driver.quit() in parallel run

I am running test in parallel using parallel="classes". Till now i was closing browser using driver.close() in #AfterClass. Once test is run, window would close.
public class DriverFactory {
public WebDriver getDriver() {
return setupChromeDriver();
}
}
public class Base {
private final ThreadLocal<WebDriver> driver = new ThreadLocal<>();
#BeforeClass
public void initialise() {
driver.set(DriverFactory.getInstance().getDriver());
}
public WebDriver getDriver() {
return driver.get();
}
#AfterClass
public void closeBrowser() {
driver.get().close();
driver.get().remove();
}
}
Recently i realised close() does not end driver session which caused many chromedriver and geckodriverinstances to stay in memory after test suite is run. I had to kill manually using killall chromedriver.
Solution :
I tried with driver.quit() in #AfterClass, which worked fine and killed session nicely but it worked for test which are not running in parallel.
Challenge:
If i use quit() for parallel run, it closes all running windows. If i use it in #AfterSuite, it will work but it would not be ideal to leave all browser windows open until complete test suite is run . I have around 200 tests.
If i use close() in #AfterClass and use quit() in #AfterSuite, it gives no such session exception because driver is closed which is correct.
Chrome version : 83.0.4103.61
Chromedriver version : 83.0.4103.39
Selenium version : 3.141.59
Any help is appreciated here, thanks .

silverlight 4, dynamically loading xap modules

I know that it is possible to load xap modules dynamically using Prism or MEF framework. However, I'd like not to use those frameworks; instead load my xap files manually. So, I created the following class (adapted from internet):
public class XapLoader
{
public event XapLoadedEventHandler Completed;
private string _xapName;
public XapLoader(string xapName)
{
if (string.IsNullOrWhiteSpace(xapName))
throw new ArgumentException("Invalid module name!");
else
_xapName = xapName;
}
public void Begin()
{
Uri uri = new Uri(_xapName, UriKind.Relative);
if (uri != null)
{
WebClient wc = new WebClient();
wc.OpenReadCompleted += onXapLoadingResponse;
wc.OpenReadAsync(uri);
}
}
private void onXapLoadingResponse(object sender, OpenReadCompletedEventArgs e)
{
if ((e.Error == null) && (e.Cancelled == false))
initXap(e.Result);
if (Completed != null)
{
XapLoadedEventArgs args = new XapLoadedEventArgs();
args.Error = e.Error;
args.Cancelled = e.Cancelled;
Completed(this, args);
}
}
private void initXap(Stream stream)
{
string appManifest = new StreamReader(Application.GetResourceStream(
new StreamResourceInfo(stream, null), new Uri("AppManifest.xaml",
UriKind.Relative)).Stream).ReadToEnd();
XElement deploy = XDocument.Parse(appManifest).Root;
List<XElement> parts = (from assemblyParts in deploy.Elements().Elements()
select assemblyParts).ToList();
foreach (XElement xe in parts)
{
string source = xe.Attribute("Source").Value;
AssemblyPart asmPart = new AssemblyPart();
StreamResourceInfo streamInfo = Application.GetResourceStream(
new StreamResourceInfo(stream, "application/binary"),
new Uri(source, UriKind.Relative));
asmPart.Load(streamInfo.Stream);
}
}
}
public delegate void XapLoadedEventHandler(object sender, XapLoadedEventArgs e);
public class XapLoadedEventArgs : EventArgs
{
public Exception Error { get; set; }
public bool Cancelled { get; set; }
}
The above code works fine; I can load any xap the following way:
XapLoader xapLoader = new XapLoader("Sales.xap");
xapLoader.Completed += new XapLoadedEventHandler(xapLoader_Completed);
xapLoader.Begin();
Now, I have a UserControl called InvoiceView in the Sales.xap project, so I would like to instantiate the class. In the current project (Main.xap) I added reference to Sales.xap project, however, since I load it manually I set "Copy Local = False". But when executed, the following code throws TypeLoadException:
Sales.InvoiceView view = new Sales.InvoiceView();
It seems the code can't find InvoiceView class. But I checked that XapLoader's initXap() method was successfully executed. So why the code can't find InvoiceView class? Can someone help me with this problem?
This is based on the asker's self-answer below, rather than the question.
If you delete a project/module the output DLLs/XAP files do hang around. If you click the "show all files" button you will see some these left-over output files in your clientbin, bin and obj folders of related projects.
You can delete them individually from the project, or, when in doubt, search for all BIN and OBJ (e.g. using desktop explorer) and delete all those folders. The BIN/CLIENTBIN/OBJ folders will be recreated when needed (this the job that the "clean" option in Visual Studio should have done!)
Hope this helps.
Ok, I found the cause. The above code works. After creating a new silverlight project (Sales.xap) I happened to compile my solution once. Then I deleted App class in the Sales.xap and renamed default MainPage class to SalesView. However, no matter how many times I compile my solution, Visual Studio's development web server was loading the first version of Sales.xap (where from?), so my code couldn't find SalesView. In my host Asp.Net project I set development server's port to a different port number, and the problem gone. So the problem was with Visual Studio's development server. Apparently it is keeping compiled xap files in some temporary folder, and doesn't always update those xap files when source code changed.
What I do to avoid such problems when executing freshly compiled Silverlight is clear the browser cache, chrome even has a clear silverlight cache ;)
this XAP Cache phenomena is often due to the visual studio embedded web server (ASP.NET Development Server).
Just stop the occurence of this server and the cache will be cleared.
Start again your project and the latest build of your xap is called.

Silverlight communication with XML RPC console server

I want to comunicate with Console XML RPC server from my silvelight application. Is it possibile?
Steps:
1. Start the Console XML RPC server
Code for Console XML RPC server is this:
using System;
using System.Collections;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Http;
using CookComputing.XmlRpc;
public class StateNameServer : MarshalByRefObject, IStateName
{
public string GetStateName(int stateNumber)
{
return "whatever";
}
}
class _
{
static void Main(string[] args)
{
IDictionary props = new Hashtable();
props["name"] = "MyHttpChannel";
props["port"] = 5678;
HttpChannel channel = new HttpChannel(props,null,new XmlRpcServerFormatterSinkProvider());
ChannelServices.RegisterChannel(channel,false);
RemotingConfiguration.RegisterWellKnownServiceType(
typeof(StateNameServer),"statename.rem",WellKnownObjectMode.Singleton);
Console.WriteLine("Press <ENTER> to shutdown");
Console.ReadLine();
}
}
Run Silverlight application
I used the code from http://code.google.com/p/xmlrpc-silverlight/
I created new Silverlight application to which I have attached the code from that link. When I start web site (in localhost with port 1139) which executes my SL app happens SecurityException.
void ResponseResponse(IAsyncResult result)
{
XmlRpcHelperRequestState state = result.AsyncState as XmlRpcHelperRequestState;
try
{
state.Response = (HttpWebResponse)state.Request.EndGetResponse(result);
...
}
catch (Exception e)
{
// comes here with SecurityException
}
finally
{
...
}
}
I am using VS2008 Professional,XP Professional, .net 3.5, Silverlight3. I will gladly provide any additional information (or code) which is needed.
I suspect that this is a case of a missing clientaccesspolicy.xml file.
Since your silverlight app will have been launched from another authority it will attempt to access this file the http://localhost:5678/. Since you little test doesn't support that file Silverlight blocks this cross "domain" activity.

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