internal static void ShowHelpButton(Window window, HelpButtonClicked callbackDelegate)
{
var hwnd = GetWindowHwnd(window);
var value = GetWindowLong(hwnd, GWL_EXSTYLE);
DisableSystemButtons(window, SystemButton.Minimize | SystemButton.Maximize);
value |= WS_EX_CONTEXTHELP;
SetWindowLong(hwnd, GWL_EXSTYLE, value);
Internal.WindowMessageHelper.RegisterWindowsMessages(window, callbackDelegate);
}
internal static void ShowHelpButton(Window window, HelpButtonClicked callbackDelegate)
{
var hwnd = GetWindowHwnd(window);
var value = GetWindowLong(hwnd, GWL_EXSTYLE);
DisableSystemButtons(window, SystemButton.Minimize | SystemButton.Maximize);
value |= WS_EX_CONTEXTHELP;
SetWindowLong(hwnd, GWL_EXSTYLE, value);
Internal.WindowMessageHelper.RegisterWindowsMessages(window, callbackDelegate);
}
internal static void RegisterWindowsMessages(Window window, HelpButtonClicked callback)
{
((HwndSource) PresentationSource.FromVisual(window)).AddHook(new HwndSourceHook(WindowMessage));
_window = window;
_callback = callback;
}
internal static void RegisterWindowsMessages(Window window, HelpButtonClicked callback)
{
((HwndSource)PresentationSource.FromVisual(window)).AddHook(new HwndSourceHook(WindowMessage));
_window = window;
_callback = callback;
}
protected internal virtual void OnHelpButtonClicked(EventArgs e)
{
HelpButtonClicked?.Invoke(this, e);
}
/// <summary>
/// Hides the minimize and maximize buttons and displays a help button (?) instead of them.
/// </summary>
/// <param name="target"></param>
/// <param name="callbackDelegate">The function to be called when the ?-button is clicked.</param>
public static void ShowHelpButton(this Window target, HelpButtonClicked callbackDelegate)
{
Internal.SystemMenuManager.ShowHelpButton(target, callbackDelegate);
}
private void HELP_BUTTON_Click(object sender, EventArgs e)
{
HelpButtonClicked?.Invoke( );
}
/// <summary>
/// Hides the minimize and maximize buttons and displays a help button (?) instead of them.
/// </summary>
/// <param name="target"></param>
/// <param name="callbackDelegate">The function to be called when the ?-button is clicked.</param>
public static void ShowHelpButton(this Window target, HelpButtonClicked callbackDelegate)
{
Internal.SystemMenuManager.ShowHelpButton(target, callbackDelegate);
}
