using System.Threading;

using System.Windows.Threading;

namespace System.Windows.Controls

{

/// <summary>

/// Helper methods to focus.

/// </summary>

public static class FocusHelper

{

#region Public methods

public static void Focus(EditTextBox element)

{

//System.Diagnostics.Debug.WriteLine("Focus textbox with helper:" + element.Text);

FocusCore(element);

element.BringIntoView();

}

public static void Focus(MultiSelectTreeViewItem element, bool bringIntoView = false)

{

//System.Diagnostics.Debug.WriteLine("FocusHelper focusing " + (bringIntoView ? "[into view] " : "") + element.DataContext);

FocusCore(element);

if (bringIntoView)

{

FrameworkElement itemContent = (FrameworkElement) element.Template.FindName("headerBorder", element);

if (itemContent != null) // May not be rendered yet...

{

itemContent.BringIntoView();

}

}

}

public static void Focus(MultiSelectTreeView element)

{

//System.Diagnostics.Debug.WriteLine("Focus Tree with helper");

FocusCore(element);

element.BringIntoView();

}

private static void FocusCore(FrameworkElement element)

{

//System.Diagnostics.Debug.WriteLine("Focusing element " + element.ToString());

//System.Diagnostics.Debug.WriteLine(Environment.StackTrace);

if (!element.Focus())

{

//System.Diagnostics.Debug.WriteLine("- Element could not be focused, invoking in dispatcher thread");

element.Dispatcher.BeginInvoke(DispatcherPriority.Input, new ThreadStart(() => element.Focus()));

}

#if DEBUG

// no good idea, seems to block sometimes

int i = 0;

while (i < 5)

{

if (element.IsFocused)

{

//if (i > 0)

// System.Diagnostics.Debug.WriteLine("- Element is focused now in round " + i + ", leaving");

return;

}

Thread.Sleep(20);

i++;

}

//if (i >= 5)

//{

// System.Diagnostics.Debug.WriteLine("- Element is not focused after 500 ms, giving up");

//}

#endif

}

#endregion Public methods

}

}