I have a WinForms project from which I want to open a WPF window from a WPF user control project.
But when I create an instance of the WPF window and call Show(), the bootstrapper isn't loaded. In an Windows Application, it's located in the App.xaml, but an user control project doesn't have this.
What can I do?
Thanks!
The only thing accomplished by having the bootstrapper in App.xaml's resources is instantiation of the bootstrapper and keeping a reference so it isn't garbage-collected. You could try making it instantiate like this:
public class SomeClass {
static Bootstrapper _bs = new Bootstrapper();
...
}
That will make sure it's initialized as part of static construction, which happens sometime before you can create an instance of SomeClass. You may have to experiment to see whether that should happen in your UserControl or in your Window.
I have a console application which presents a WPF gui that I made with Caliburn.Micro. I present the GUI like this:
_App = new App();
_App.Run();
Where App.xaml contains the bootstrapper and the main thread is STA like this:
[STAThread]
static int Main(string[] args)
{ ... }
I know your situation is different but maybe this will give you an idea.
Console application test:
Add MaterialDesignColors pakage
[System.STAThreadAttribute()]
static void Main(string[] args)
{
var _app = new App();
_app.InitializeComponent();
_app.Run();
_app.Shutdown();
}
Related
My app works fine, but now I wanted to have custom startup, so I could catch any errors, add my logging from the start, etc.
So I used approach as shown in this answer What code controls the startup of a WPF application?
[STAThread]
public static void Main(string[] args) {
//include custom startup code here
var app = new MyApplication();//Application or a subclass thereof
var win = new MyWindow();//Window or a subclass thereof
app.Run(win); //do WPF init and start windows message pump.
}
It works fine with one exception -- SynchronizationContext.Current is null. And I need it :-)
So how to correctly make custom startup and have synchronization context?
Don't create your own Main method. Override the OnStartup method in your App.xaml.cs file:
public partial class App : Application
{
protected override void OnStartup(StartupEventArgs e)
{
base.OnStartup(e);
var win = new MyWindow();
win.Show();
}
}
Then you will get a SynchronizationContext as usual.
Don't forget to remove the StartupUri attribute from the <Application> root element of your App.xaml file.
When a new WPF Application project is created, MainWindow.xaml, App.xaml and their corresponding code behind classes are automatically generated. In the App.xaml there is an attribute that defines which window is going to be run initially and by the default it's StartupUri="MainWindow.xaml"
I have created a new Dispatcher class in the same project. At startup, I want the instance of that class Dispatcher to be constructed and then one of its method to run. That method would actually create and show the MainWindow window. So how do I modify the App.xaml or App.xaml.cs in order to make it happen? Or, if it cannot be done by App, how should I implement it? Thanks.
You can remove the StartupUri attribute from the App.xaml.
Then, by creating an override for OnStartup() in the App.xaml.cs, you can create your new instance of your Dispatcher class.
Here's what my quick app.xaml.cs implementation looks like:
public partial class App : Application
{
protected override void OnStartup(StartupEventArgs e)
{
base.OnStartup(e);
new MyClassIWantToInstantiate();
}
}
}
Update
I recently discovered this workaround for a bug if you use this method to customize app startup and suddenly none of the Application-level resources can be found.
Try to use the Startup event (class Application) - MSDN.
You can show MainWindow in this event handler - after you create a Dispatcher instance.
1.In App.xaml, To replace the StartupUri with a subscription to the Startup event.
Use the event in App.xaml.cs .
For instance,
Startup="Application_Startup" in .xaml.
public partial class App : Application
{
private void Application_Startup(object sender, StartupEventArgs e)
{
// Create the startup window
MainWindow wnd = new MainWindow();
// Do stuff here, e.g. to the window
wnd.Title = "Something else";
// Show the window
wnd.Show();
}
}
I want to create PRISM application with MVVM pattern and I don't know where I should put bootstrapper?
In Model, ViewModel or View?
Bootstrapper creates shell (so in View?) but it also registers container etc so maybe it should be like separate service?
The bootstrapper is part of the executable framework for configuring your application.
I suggest putting the bootstrapper code in the OnStartup event handler of your Application class.
public partial class App : Application
{
protected override void OnStartup(StartupEventArgs e)
{
SplashScreen splash = new SplashScreen("Resources\\mysplash.png");
splash.Show(true);
base.OnStartup(e);
MyBootstrapper b = new MyBootstrapper();
b.Run();
}
}
Technically, it is part of the View layer, imho, but is really there to configure the catalog and perform start-up operations.
I got my hands om MEF for a week now and I am trying to build up a WPF application that loads imported controls from MEF.
I created a WPF application project and removed the default window and application start up URI. Then I handled the application startup event to compose the application:
public partial class App : Application, IPartImportsSatisfiedNotification
{
{...}
private void App_Startup(object sender, StartupEventArgs e)
{
this.Compose();
}
public void Compose()
{
try
{
globalCatalog.Catalogs.Add(new DirectoryCatalog(extensionsDirectoryPath));
CompositionContainer container = new CompositionContainer(globalCatalog);
container.ComposeParts(this);
}
catch (Exception ex)
{
// Do something
}
}
{...}
}
Actually, when debugging and watching objects after imports are satisfied, everything has hierarchically composed fine like I wanted. But when I try to show up the MainWindow of the application an exception is thrown on MainWindow.Show() call:
"Specified element is already the logical child of another element. Disconnect it first."
Though my code in OnImportsSatisfied method seems fine as it is working when not using MEF mecanism:
public void OnImportsSatisfied()
{
Window mainWindow = new Window();
mainWindow.Content = this.importedControl;
this.MainWindow = mainWindow;
this.MainWindow.Show();
}
I insist on the fact that this works perfectly when not importing controls with MEF. What is surprising is that this code does not work too:
Window mainWindow = new Window();
//mainWindow.Content = this.importedControl;
this.MainWindow = mainWindow;
this.MainWindow.Show();
So I suspect that ComposeParts is doing a bit more than what it says as it is the only member acting on my actual application instance.
Hope someone can help me (Glenn?).
Thanks.
Edit:
I discovered that when I remove the IPartImportsSatisfiedNotification interface from my parts, no exception is thrown and the window shows up. But of course the window is empty as I need this OnImportsSatisfied method to set the DataContext of the window to its associated imported view model.
The sample applications of the WPF Application Framework (WAF) show how to use MEF within a WPF application.
I finally discovered that I was importing my WPF user controls by using the default ImportAttribute constructor, which in fact will make a shared instance of the class if the creation policy is not specified during export. And as many of my controls were implementing the same interface and I was binding them in my views, I was actually trying to add this shared user control instance to different visual elements, which is not permited by WPF (and so the exception).
I marked my imports using the RequiredCreationPolicy set to NonShared and everything got back in order! That was all about learning MEF...
I am having problems with hosting a WPF prism app in an ElementHost control and am desparate for help.
The PRISM app runs fine in silverlight and in a standalone WPF.
The main Shell seems to setup fine in the elementHost on a WinForm however other views only load with the “RegisterViewWithRegion” and not the “Add,Activate” procedure. I need “Add,Activate” for scoping. However I beleive the problem is that I am loading my shell twice … not on purpose. I cannot find a way to call the bootsrapper and set the elementHot without calling “Resolve” twice.
Here is the code for my WinForm and my bootstrapper. Again everything works when using "RegisterViewWithRegion".
Here is the Winform Constructor:
public Form1()
{
InitializeComponent();
if (System.Windows.Application.Current == null)
{
new MyApp();
}
Bootstrapper bootStrapper = new Bootstrapper();
bootStrapper.Run();
var shellElement = bootStrapper.Container.Resolve<ShellContainer>();
//Attach the WPF control to the host
elementHost.Child = shellElement;
}
Here is the bootstrapper:
public class Bootstrapper : UnityBootstrapper
{
protected override DependencyObject CreateShell()
{
return Container.Resolve<ShellContainer>();
}
protected override void InitializeModules()
{
IModule moduleSurvey = Container.Resolve<SurveyModule>();
moduleSurvey.Initialize();
}
}
The Bootstrapper automatically sets Application.Current.MainForm to whatever you returned in the CreateShell method. Hopefully you are setting up an Application (I think that's what you are doing in the first If block). If so, you can just change this:
var shellElement = bootStrapper.Container.Resolve<ShellContainer>();
To this:
var shellElement = Application.Current.MainForm;
That ought to work, but there are definitely some weirdnesses with the ElementHost. We ended up with a lot of strange rendering bugs, especially in a Citrix environment. I don't know if this is a limitation of your setup, but I thought I would mention it.
Good luck!
I had the same GCE (Gross Conceptual Error). I was seeing the same behavior of my views being instantiated twice when using Add or Activate. I was deep into debugging the behaviors when it hit me.
The following is returning a new instance of the ShellContainer.
var shellElement = bootStrapper.Container.Resolve<ShellContainer>();
Either register your ShellContainer type in the container with a ContainerControlledLifetimeManager or put a prublic property on your bootstrapper to access the ShellContainer instance to set into your ElementHost.