/// <summary>
/// Asynchronously wait for the Chromium widget window to be created for the given ChromiumWebBrowser,
/// and when created hook into its Windows message loop.
/// </summary>
/// <param name="browser">The browser to intercept Windows messages for.</param>
/// <param name="forwardAction">This action will be called whenever a Windows message is received.</param>
internal static void MessageLoop(ChromiumWebBrowser browser, Action <Message> forwardAction)
{
Task.Run(() =>
{
try
{
bool foundWidget = false;
while (!foundWidget)
{
browser?.Invoke((Action)(async() =>
{
IntPtr chromeWidgetHostHandle;
if (BrowserWidgetHandleFinder.TryFindHandle(browser, out chromeWidgetHostHandle))
{
foundWidget = true;
_ = new BrowserWidgetMessageInterceptor(browser, chromeWidgetHostHandle, forwardAction);
}
else
{
// Chrome hasn't yet set up its message-loop window.
await Task.Delay(10);
}
}));
}
}
catch
{
// Errors are likely to occur if browser is disposed, and no good way to check from another thread
}
});
}
private void OnBrowserInitializedChanged(object sender, EventArgs args)
{
if (IsBrowserInitialized)
{
BrowserWidgetMessageInterceptor.MessageLoop(this, (message) =>
{
if (message.Msg == (int)Event.LeftButtonDown)
{
var point = new Point(message.LParam.ToInt32());
var dragHandler = DragHandler as BrowserDragHandler;
if (dragHandler != null && dragHandler.DraggableRegion.IsVisible(point))
{
Native.ReleaseCapture();
SendHandleMessage();
}
}
});
}
}