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C# .NET Window won't show in front after double clicking on listview row

I have this one problem that I can't get over. I think it will be something really simple but I just was not able to find out.. I am trying to open new window here for editing contact when user double click on one row in listview. Window normally opens but the problem is it won't open in front of current main window but behind it so it is not visible and can easily confuse user. I have tried few methods like BringIntoView() or playing with focus but nothing helped.
Please help me with this. Thanks!
Code:
void ListViewItem_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
editContact();
}
private void editContact()
{
Window1 win = new Window1("edit");
DatabaseHandler handler = new DatabaseHandler();
win.Show();
List<Contact> listie = handler.GetContactList();
var selected = listview_contacts.SelectedItem as Contact;
win.textbox_id.Text = selected.cId.ToString();
win.textbox_name.Text = selected.Name.ToString();
win.textbox_address.Text = selected.Address.ToString();
win.textbox_email.Text = selected.Email.ToString();
win.textbox_name.Focus();
win.textbox_name.SelectionStart = win.textbox_name.Text.Length;
}

private void editContact()
{
using(Window1 win = new Window1("edit"))
{
DatabaseHandler handler = new DatabaseHandler();
List<Contact> listie = handler.GetContactList();
var selected = listview_contacts.SelectedItem as Contact;
win.textbox_id.Text = selected.cId.ToString();
win.textbox_name.Text = selected.Name.ToString();
win.textbox_address.Text = selected.Address.ToString();
win.textbox_email.Text = selected.Email.ToString();
win.textbox_name.Focus();
win.textbox_name.SelectionStart = win.textbox_name.Text.Length;
win.ShowDialog();
// do something with whatever win1 did.
// if its say OK Cancrl form
// if (win.ShowDialog() == DialogResult.OK) { // do something }
}
}
Will probably fix your issue. However without seeing the rest of your code, or knowing your intent, I can't tell you exactly how badly you've gone wrong.
For example at least all the code setting up win.textbox, should be in win...

Try
win.ShowDialog();
Which should open the new windows as a modal window.

You could try
win.Show(this);
This will enable the user to interact with the main form when your editing dialog opens.
Or you can try
win.ShowDialog();
This will block the main form when your editing dialog opens.

WPF modal progress window

I apologize if this question has been answered tons of times, but I can't seem to find an answer that works for me. I would like to create a modal window that shows various progress messages while my application performs long running tasks. These tasks are run on a separate thread and I am able to update the text on the progress window at different stages of the process. The cross-thread communication is all working nicely. The problem is that I can't get the window to be on top of only other application windows (not every application on the computer), stay on top, prevent interaction with the parent window, and still allow the work to continue.
Here's what I've tried so far:
First, my splash window is a custom class that extends the Window class and has methods to update the message box. I create a new instance of the splash class early on and Show/Hide it as needed.
In the simplest of cases, I instantiate the window and call .Show() on it:
//from inside my secondary thread
this._splash.Dispatcher.Invoke(new Action(() => this._splash.Show());
//Do things
//update splash text
//Do more things
//close the splash when done
this._splash.Dispatcher.Invoke(new Action(() => this._splash.Hide());
This correctly displays the window and continues running my code to handle the initialization tasks, but it allows me to click on the parent window and bring that to the front.
Next I tried disabling the main window and re-enabling later:
Application.Current.Dispatcher.Invoke(new Action(() => this.MainWindow.IsEnabled = false));
//show splash, do things, etc
Application.Current.Dispatcher.Invoke(new Action(() => this.MainWindow.IsEnabled = true));
This disables all the elements in the window, but I can still click the main window and bring it in front of the splash screen, which is not what I want.
Next I tried using the topmost property on the splash window. This keeps it in front of everything, and in conjunction with setting the main window IsEnabled property I could prevent interaction, but this makes the splash screen appear in front of EVERYTHING, including other applications. I don't want that either. I just want it to be the topmost window within THIS application.
Then I found posts about using .ShowDialog() instead of .Show(). I tried this, and it correctly showed the dialog and did not allow me to click on the parent window, but calling .ShowDialog() makes the program hang waiting for you to close the dialog before it will continue running code. This is obviously, not what I want either. I suppose I could call ShowDialog() on a different thread so that that thread would hang but the thread doing the work would not...is that the recommended method?
I have also considered the possibility of not using a window at all and instead putting a full-sized window element in front of everything else on the page. This would work except that I have other windows I open and I'd like to be able to use the splash screen when those are open too. If I used a window element I would have to re-create it on every window and I wouldn't be able to use my handy UpdateSplashText method in my custom splash class.
So this brings me to the question. What is the right way to handle this?
Thanks for your time and sorry for the long question but details are important :)

You are correct that ShowDialog gives you most of the UI behavior that you want.
It does have the problem that as soon as you call it you block execution though. How could you possibly run some code after you show the form, but define what it should be before it's shown? That's your problem.
You could just do all of the work within the splash class, but that's rather poor practice due to tight coupling.
What you can do is leverage the Loaded event of Window to define code that should run after the window is shown, but where it is defined before you show it.
public static void DoWorkWithModal(Action<IProgress<string>> work)
{
SplashWindow splash = new SplashWindow();
splash.Loaded += (_, args) =>
{
BackgroundWorker worker = new BackgroundWorker();
Progress<string> progress = new Progress<string>(
data => splash.Text = data);
worker.DoWork += (s, workerArgs) => work(progress);
worker.RunWorkerCompleted +=
(s, workerArgs) => splash.Close();
worker.RunWorkerAsync();
};
splash.ShowDialog();
}
Note that this method is designed to encapsulate the boilerplate code here, so that you can pass in any worker method that accepts the progress indicator and it will do that work in a background thread while showing a generic splash screen that has progress indicated from the worker.
This could then be called something like this:
public void Foo()
{
DoWorkWithModal(progress =>
{
Thread.Sleep(5000);//placeholder for real work;
progress.Report("Finished First Task");
Thread.Sleep(5000);//placeholder for real work;
progress.Report("Finished Second Task");
Thread.Sleep(5000);//placeholder for real work;
progress.Report("Finished Third Task");
});
}

The accepted answer from #Servy helped me a lot! And I wanted to share my Version with the async and MVVM approach. It also contains a small delay to avoid "window flickering" for too fast operations.
Dialog Method:
public static async void ShowModal(Func<IProgress<string>, Task> workAsync, string title = null, TimeSpan? waitTimeDialogShow = null)
{
if (!waitTimeDialogShow.HasValue)
{
waitTimeDialogShow = TimeSpan.FromMilliseconds(300);
}
var progressWindow = new ProgressWindow();
progressWindow.Owner = Application.Current.MainWindow;
var viewModel = progressWindow.DataContext as ProgressWindowViewModel;
Progress<string> progress = new Progress<string>(text => viewModel.Text = text);
if(!string.IsNullOrEmpty(title))
{
viewModel.Title = title;
}
var workingTask = workAsync(progress);
progressWindow.Loaded += async (s, e) =>
{
await workingTask;
progressWindow.Close();
};
await Task.Delay((int)waitTimeDialogShow.Value.TotalMilliseconds);
if (!workingTask.IsCompleted && !workingTask.IsFaulted)
{
progressWindow.ShowDialog();
}
}
Usage:
ShowModal(async progress =>
{
await Task.Delay(5000); // Task 1
progress.Report("Finished first task");
await Task.Delay(5000); // Task 2
progress.Report("Finished second task");
});
Thanks again #Servy, saved me a lot of time.

You can use the Visibility property on Window to hide the whole window while the splash screen runs.
XAML
<Window ... Name="window" />
Code
window.Visibility = System.Windows.Visibility.Hidden;
//show splash
//do work
//end splash
window.Visibility = System.Windows.Visibility.Visible;

You can have your progress window's constructor take a Task and then ensure the window calls task.Start on the OnLoaded event. Then you use ShowDialog from the parent form, which will cause the progress window to start the task.
Note you could also call task.Start in the constructor, or in the parent form anywhere before calling ShowDialog. Whichever makes most sense to you.
Another option would be just to use a progress bar in the status strip of the main window, and get rid of the popup. This option seems to be more and more common these days.

I found a way to make this work by calling ShowDialog() on a separate thread. I created my own ShowMe() and HideMe() methods in my dialog class that handle the work. I also capture the Closing event to prevent closing the dialog so I can re-use it.
Here's my code for my splash screen class:
public partial class StartupSplash : Window
{
private Thread _showHideThread;
public StartupSplash()
{
InitializeComponent();
this.Closing += OnCloseDialog;
}
public string Message
{
get
{
return this.lb_progress.Content.ToString();
}
set
{
if (Application.Current.Dispatcher.Thread == System.Threading.Thread.CurrentThread)
this.lb_progress.Content = value;
else
this.lb_progress.Dispatcher.Invoke(new Action(() => this.lb_progress.Content = value));
}
}
public void ShowMe()
{
_showHideThread = new Thread(new ParameterizedThreadStart(doShowHideDialog));
_showHideThread.Start(true);
}
public void HideMe()
{
//_showHideThread.Start(false);
this.doShowHideDialog(false);
}
private void doShowHideDialog(object param)
{
bool show = (bool)param;
if (show)
{
if (Application.Current.Dispatcher.Thread == System.Threading.Thread.CurrentThread)
this.ShowDialog();
else
Application.Current.Dispatcher.Invoke(new Action(() => this.ShowDialog()));
}
else
{
if (Application.Current.Dispatcher.Thread == System.Threading.Thread.CurrentThread)
this.Close();
else
Application.Current.Dispatcher.Invoke(new Action(() => this.Close()));
}
}
private void OnCloseDialog(object sender, CancelEventArgs e)
{
e.Cancel = true;
this.Hide();
}
}

How to determine connection is failed while window is opened

I've an editor window opened. And, I've a requirement to check that if it fails to connect to database or, connection is broken when window is opened, the window should be closed.
var window = new EditorWindow(group);
window .KeyDown += (sender, args) =>{
if (args.Key == Key.Escape)
window .Close();
};
DialogHelper.ShowDialog(window);
And, for the change of database connection I've:
public dbState dbState
{
get { return dbState ; }
private set
{
dbState = value;
FirePropertyChanged("dbState ");
}
}
I'm new to WPF so any help would be appreciated. Thank you in advance.

If you are wiring things up directly, you would add code inside your EditorWindow class subscribing to the dbState property change event, and when that even fires, in your handler you would call this.Close() method to close the window. See http://msdn.microsoft.com/en-us/library/ms748948.aspx for more details.
A cleaner way to do it would be to use an MVVM library and take advantage of event aggregation. For example, this is how Caliburn.Micro does it: http://caliburnmicro.codeplex.com/wikipage?title=The%20Event%20Aggregator.

C# Close processes minimized to tray in a graceful way?

I have an application that has can display a window using a Form. The form is only shown if the application is run using a -debug flag, otherwise it is only shown in tray.
var form = new Form();
if(DebugMode)
form.Show();
The application listens to CloseMainWindow() when run in debug mode, as the form is shown.
How can I make the application also listen to CloseMainWindow() without showing it? I don't want the user to be able to interact with the form if not in debug mode.
I've tried several approaches, like displaying the window but setting the size to 0. This shows a small form, i.e. not hidden.
if (!DebugMode)
{
form.Show();
form.Size = new Size(0, 0);
}
Also showing it, and then hiding it does not work:
if (!DebugMode)
{
form.Show();
form.Hide();
}
Showing it, but started minimized and not shown in taskbar does not work either:
if (!DebugMode)
{
form.Show();
form.WindowState = FormWindowState.Minimized;
form.ShowInTaskbar = false;
}
Am I missing something really obvious here, or is it not possible to close processes minimized to tray in a graceful way?

If i've understood the problem correctly, you want to completely hide the form when not in debug mode (i.e. the window is not seen anywhere but in the task manager) and when someone kills the process via task manager, you want to execute some code for clean-up or just get notified.
Basing my solution on this assumption, the following code should work
public static bool DebugMode = false;
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
var form = new Form1();
form.Load += (s, e) =>
{
if (!DebugMode)
{
form.Opacity = 0;
form.ShowInTaskbar = false;
}
};
form.FormClosing += (s, e) =>
{
// Breakpoint hits
};
Application.Run(form);
}

I'm not sure you can do it through Process.CloseMainWindow(). Processes with no visible main window, I seem to recall, have MainWindowHandle set to IntPtr.Zero.
You need some kind of workaround. My advice is to keep track manually of the MainWindow Handles yourself:
static void Main()
{
...
MainWindow mainWindow = new MainWindow();
[HandleRepository] = mainWindow.Handle;
Application.Run(mainWindow);
}
Then when you want to close the process, do it with a workaround:
public void EndProcess()
{
Form mainWindow= (MainWindow)Form.FromHandle([HandleRepository]);
mainWindow.Close();
}
Might not be the most elegant solution but it should work (haven't tested it)

WindowsFormsApplicationBase SplashScreen makes login form ignore keypresses until I click on it - how to debug?

My WinForms app has a simple modal login form, invoked at startup via ShowDialog(). When I run from inside Visual Studio, everything works fine. I can just type in my User ID, hit the Enter key, and get logged in.
But when I run a release build directly, everything looks normal (the login form is active, there's a blinking cursor in the User ID MaskedEditBox), but all keypresses are ignored until I click somewhere on the login form. Very annoying if you are used to doing everything from the keyboard.
I've tried to trace through the event handlers, and to set the focus directly with code, to no avail.
Any suggestions how to debug this (outside of Visual Studio), or failing that - a possible workaround?
Edit
Here's the calling code, in my Main Form:
private void OfeMainForm_Shown(object sender, EventArgs e)
{
OperatorLogon();
}
private void OperatorLogon()
{
// Modal dialogs should be in a "using" block for proper disposal
using (var logonForm = new C21CfrLogOnForm())
{
var dr = logonForm.ShowDialog(this);
if (dr == DialogResult.OK)
SaveOperatorId(logonForm.OperatorId);
else
Application.Exit();
}
}
Edit 2
Didn't think this was relevant, but I'm using Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase for it's splash screen and SingleInstanceController support.
I just commented out the splash screen code, and the problem has disappeared. So that's opened up a whole new line of inquiry...
Edit 3
Changed title to reflect better understanding of the problem

UI focus/redraw/etc. issues usually are rather straightforward to debug by using remote-debugging. I.e. use a second PC (virtual is just enough) where your application runs.
See this MSDN article for details.

Run this in your form code behind. It will tell you which control has focus by giving you the type and name of the control. Run it in form_shown because its the last event in the form load process.
private void Form1_Shown(object sender, EventArgs e)
{
Control control = FindFocusedControl(this);
MessageBox.Show("The focused control " + control.Name + " is of type " + control.GetType());
}
public static Control FindFocusedControl(Control control)
{
var container = control as ContainerControl;
while (container != null)
{
control = container.ActiveControl;
container = control as ContainerControl;
}
return control;
}
If the answer isn't obvious after that, tell us what you get.

I've found a hack...er...I mean...workaround, that fixes the problem. The solution was buried in one of the comments of this answer (thanks, P. Brian Mackey, for providing the link to the related question!)
The workaround is to minimize the main window while the splash screen is displayed, then set it's WindowState back to Normal before showing the login form.
In the code below, see the lines commented with "HACK".
public class SingleInstanceController : WindowsFormsApplicationBase
{
public SingleInstanceController()
{
this.IsSingleInstance = true;
}
/// <summary>
/// When overridden in a derived class, allows a designer to emit code that
/// initializes the splash screen.
/// </summary>
protected override void OnCreateSplashScreen()
{
this.SplashScreen = new SplashScreen();
}
/// <summary>
/// When overridden in a derived class, allows a designer to emit code that configures
/// the splash screen and main form.
/// </summary>
protected override void OnCreateMainForm()
{
// SplashScreen will close after MainForm_Load completed
this.MainForm = new OfeMainForm();
// HACK - gets around problem with logon form not having focus on startup
// See also OfeMainForm_Shown in OfeMainForm.cs
this.MainForm.WindowState = FormWindowState.Minimized;
}
}
public partial class OfeMainForm : Form
{
// ...
private void OfeMainForm_Shown(object sender, EventArgs e)
{
// HACK - gets around problem with logon form not having focus on startup
// See also OnCreateMainForm in Program.cs
this.WindowState = FormWindowState.Normal;
OperatorLogon();
}
// ...
}
This is working for now, but I'm wondering if I should explicitly open the Logon form from the SingleInstanceController, rather than from my main form.